Aerobic Exercise & Strength Training- Does It Help Or Hurt?

One of the greatest obstacles to the realization of our fullest potential in any field is the idea of convention. Convention can heartily sustain the life force of myths and concepts poorly understood by the public at large, even when confronted by volumes of well researched science that contradicts them. Nowhere is the hold of convention more pronounced than in the related fields of diet and exercise, where training protocols are often prescribed or implemented based on what is popular or what everyone has traditionally done. Not much thought is given to whether the programs are necessarily the best practices for the goals sought. The universal recommendation that aerobic exercise needs to be a part of everyone’s strength training regime is a case in point, as volumes of research highlight the negative impact of aerobic exercise on strength training, power development and muscle development. Not that there is anything wrong with aerobic and distance training, as it does indeed serve several purposes. Its health benefits are many and well documented. However, most employ aerobic exercise as a way of reducing body fat, building endurance or improving recovery time. All these benefits can be better achieved through other more anaerobic based and time efficient forms of conditioning such as high intensity training [1,2,3,4] and attention to dietary intake. More importantly numerous studies have shown that concurrent aerobic exercise can in many cases negatively impact strength and power gains as well as increase the likelihood of overtraining and bring about negative hormonal responses to exercise even when used in relatively small amounts. [1, 5,6,7,8] Such findings disqualify aerobics as a universal requirement for everyone, especially those interested in optimizing strength, power and or muscle mass to their fullest potential. A group that includes not only athletes whose disciplines require maximum strength and power output but also those seeking the toned, tight and sculpted body and those wishing to increase strength and skeletal muscle as a means of decreasing the motor related decline that comes with aging. [9]

The Impact of Aerobic Exercise on Adaptations For Power & Strength

The human body is a very specific machine, one that is individually adapted to the very stresses that it encounters throughout the course of everyday life. The process of increasing strength and muscle mass is in fact a stress response adaptation to a very specific form of overload. When lifting weights, for example, at a level of intensity or with a load sufficient enough to trigger a need for our body to adapt, a number of hormonal, neuromuscular and chemical events occur. Events that lead to an adaptive anabolic environment that can promote increases in muscle size and or increased ability to generate force. (See my Article on How Muscles Get Bigger & Stronger) By engaging in sustained steady state aerobic exercise such as distance running, our body is exposed to a very different form of stress-and the adaptations for this form of activity are far different than those required for increased power, strength and muscle mass. The physique of a sprinter is far different from that of a marathon runner as the two activities create different physical adaptations thus it should come as no surprise that many studies confirm that continued aerobic exercise can bring about decreases in muscle power. This may be due to neuromuscular and hormonal adaptations favorable for reducing the amount of energy expended while exercising- factors which would make an endurance athlete more efficient as opposed to maximizing mechanical power.[1] The sheer volume requirement of endurance type training as well may be a consideration as well as it appears to interfere with the recovery required for maximal results from strength and power training.[7]

The Impact Of Aerobic Training On Power and Rate Of Force Development

Explosive movements require great power or speed of execution

Repetitive activity associated with aerobic exercise has been shown to reduce the ability to generate force in the high velocity, low frequency region of the force velocity curve- in other words it makes our muscles less powerful.(30) Power and strength are closely related but not exactly the same thing. Strength is defined as the capacity for gross muscular effort. Power on the other hand refers to the speed at which effort can be performed. Its development is paramount for athletic performance since most movements in any sporting discipline are executed as forcefully and as quickly as possible.[1] Even in sports that one might consider primarily aerobic in nature such as basketball or soccer due their extended duration of play actually consist of repeated bouts of explosive movements that make up a very small proportion of playing time. [9,10] A good example of differences between power and strength would be a comparison between a powerlifter bench pressing 440lbs and an Olympic level 100m sprinter exploding out of the blocks. Both movements require the abilty to generate larger forces at high speeds, but the sprinter’s acceleration would be almost twice as powerful as the powerlifter. Contrast that with the amount of high speed force required by a baseball player to swing a bat from maximal backswing to contact with the ball where the baseball player generates just under ten times more force than the powerlifter bench pressing 440lbs. The baseball player would not likely be able to lift as much as the powerlifter, but he or she might be more powerful. That being said, you can be strong and not powerful but you can’t be powerful without a certain base of strength as the two are very directly related. (The most powerful athletes, Olympic lifters are indeed the strongest.) Now we have an understanding of the significance of strength and power, we can look at how it can be affected by distance type training.

While a heavy bench press requires great strength the movement does not require as much explosive power as a sprinter leaving the start line.

A study published in the European Journal of Applied Physiology took an in-depth look at how power is affected when individuals do strength training concurrently with endurance training as opposed to strength training on its own. During the three week study, two groups of male participants were made to train twice a week doing the same program of resistance exercise with one group doing an additional two days of continuous aerobic exercise on a rowing machine with sessions lasting anywhere from 30 to 60 minutes in duration. At the end of the study there were similar increases in maximum one repetition lifts and isometric strength tests, but only the strength training group saw an increase in rate of force development (ROFD) and the associated rapid neural activation. No changes whatsoever were observed in the group doing both strength training and aerobic exercise.[12] Rate of force development refers to the speed at which force can be produced and a faster ROFD means you are able to do quicker and more explosive movements- qualities essential for strength increases as well as athletic performance. The study concluded that even small amounts of aerobic exercise can lead to interference in explosive strength development.[1]

How Aerobic Exercise Affects Muscle Development for Maximum Power & Muscle Mass

Other studies have demonstrate that sustained aerobic type exercise not only affects rate of force development, but also decreases peak power development through changes in the way muscles are recruited. There are basically two types of skeletal muscle fibers in our bodies Type I and Type II. (See the chart above for a detailed breakdown of the differences.) Type I fibers are what you would recruit primarily if you were running or doing any form of sustained aerobic activity for a considerable amount of time (usually longer than 30 minutes) and someone like a successful marathon runner would tend to have a fairly high distribution of them as an adaption to the sustained endurance training they undergo. Such fibers are highly resistant to fatigue, have a dense network amount of capillaries transporting oxygen rich blood to them and use triglycerides (fats) as their primary fuel source. (Thus the origin of the idea that aerobic activity is best for burning body fat- which it is not- See my article on Rethinking the Need for Aerobics) Not to get too technical but Type I fibers gain their resistance to fatigue from their ability to generate ATP (an important muscle fuel source) through the use of oxygen (aerobic metabolism) which is provided by the many blood vessels found in such muscle fibers.

Type II fibers are more efficient for short bursts of speed and power. These muscle fibers are not recruited to a significant extent during low intensity exercises such as endurance training.(13) Type II fibers have various sub divisions and use glycogen (and creatine phosphate) as their main fuel source and can use either anaerobic or aerobic oxidative metabolism to generate ATP. Type IIx and type IIb fibers are used primarily for explosive movement or any short term anaerobic activity. Generally, these muscle fibers are found in high distributions on more muscular athletes like bodybuilders, powerlifters and sprinters as an adaptation to the short high intensity training protocols that they regularly engage in. These fibers also produce more power than all the other fibers and rely on an anaerobic (without oxygen) metabolism to create ATP. Their development is an important part of any program where strength and power production is a primary goal, and is an important part of any regiment geared towards building lean muscle mass as other muscle fibers do not develop to the extent of these fibers. Type IIa fibers are a bit of a cross between Type II and Type I fibers as they have a fairly high resistance to fatigue and use both anaerobic and aerobic metabolism to operate. They act as a sort of a bridge between long term and short term activity and allow us to perform movements of moderate intensity for periods up to about 30 minutes.

How are muscle fibers affected by aerobic exercise? A decade long Canadian study found that subjects who regularly engaged in high intensity aerobic training verified the idea that our bodies do indeed adapt to the specific stresses it has to regularly undergo. The percentage of Type I fibers in those who regularly participated in distance training was 70.9% as opposed to 37.7 percent in the control group who did not exercise. Endurance training appeared to promote a transition from Type II to Type I fibers at the expense of the more powerful Type II fibers. Interestingly enough, Type IIa fibers in the endurance trained group members actually had a reduced aerobic capacity as a result of the years of training.[14] This decrease in percentage of fast twitch fibers significantly compromises strength and speed capabilities as high intensity conditioning requires an increase in the functional properties of fast twitch Type II fibers relative to slow twitch Type I fibers. Although in a large part individual proportions of muscle fiber types are genetically predetermined, what we do can make a large difference in how our body adapts. The more aerobic exercise you do, the greater promotion of Type I fiber -while the more explosive type anaerobic training you do can increase the proportions of Type II fibers.[15,16,17]

Effects Of Concurrent Aerobic Exercise & Strength Training On Cortisol & Testosterone Levels

Another area for concern is the impact of concurrent aerobic training with strength training on your hormone levels. Some studies have found that aerobics done in certain quantities can produce a net catabolic (breaking down) effect on muscle tissue.[1] This catabolic effect can be traced to either a decreased release of testosterone or an increase in the stress hormone cortisol from combining the two forms of training.[7] A study of US Army soldiers published in the Journal of Applied Physiology took 35 men and split them into four groups. The first group performed whole body high intensity strength training for four days a week focused on increasing muscle size and strength. The second group did upper body strength training only and the third group performed aerobic type endurance training only. A program consisting of two days of continuous aerobic exercise at 80-85% VO2max for 40 minutes and two days of interval training at 95-100% VO2max. The fourth group did a combination of both strength training and aerobic training protocols. Researchers found a significant increase in exercise induced and total cortisol response after in members of the strength & aerobics training group. Whereas those in the strength training only group saw a decrease in cortisol levels and an increase in testosterone levels. Changes that promote an anabolic environment favorable to increased muscle growth and strength increase. The study concluded that the catabolic effects noticed in the strength and aerobic trained group came as result of extreme stress placed on the adrenal glands which systematically lead to a form of overtraining.[7] Other studies of concurrent strength and aerobic type endurance training found similar increases in cortisol (a catabolic stress hormone) among those training in both modalities.[5,18]

The Role of Aerobics In Promoting Overtraining When Combined With Strength Training

Our muscles get stronger, bigger and more powerful as a direct response to the stress of exercise. However, it must be noted that these changes can only occur if the volume and or intensity of training is not so much that our bodies are unable to adapt to it. When we are unable to recover from exercise induced stress, we are said to be overtrained- and overtraining can bring about a long term decrease in performance and muscle related improvements. Recovery from overtraining can take several days to several weeks [19] and we know now that sustained aerobic exercise combined with strength training may result in less than optimal hormonal profiles and other factors associated with overtraining. (5,7,19)

The human body has a limited set of resources available to it to help recover from the stress of exercise. An insufficient recovery is the central causative factor of overtraining. That being said, given the large volume of exercise that accompanies conventional endurance based aerobic training, the amount of repetitive stress placed on joints during such forms of continuous exercise and the large amount of energy substrates consumed, it is not surprising that the stage is set for overtraining when it is combined with the rigors of high intensity anaerobic training.[1] The increase in oxidative stress during continued aerobic type training may also have a negative impact on net protein turnover. This impact can result in muscle fiber atrophy [20]. All of the aforementioned factors create an environment that prevents optimal adaptation to strength and power training.(1)

Inadequate recovery can also lead to a lasting fatigue that diminishes the ability to develop tension during power and strength movements. Reduction in power generation from overly high training volume then reduces your ability to learn and master power related skills [21,22,23] while also increasing your risk for injury. The common scenario for people starting an exercise program that includes both weight training and aerobics is that they tend to quit several weeks into the program after an enthusiastic start. Considering the amount of stress inflicted on the body by combining both modes of training it is no surprise that an otherwise untrained individual would experience fatigue and a psychological aversion to training over time. It wouldn’t be because of a lack of willpower or consistency but simply because they are overtrained.

Alternatives to Aerobic Exercise for Endurance Development

Aerobic fitness is indeed an important component for both health and athletic performance. However, prolonged aerobic exercise isn’t the only way to increase endurance and cardiovascular capacity nor is it the most efficient. High intensity training and high intensity interval training has been shown to produce metabolic endurance adaptations similar to and in some cases superior to aerobic exercise.[24, 25, 26] (Read my article here on high intensity training and endurance) Other studies found that similar increases in maximal aerobic capacity (VO2max) and improvements in 1 mile run times can occur not just as a result of high volume continuous endurance training but also from high intensity interval training as well. Interval training however takes less time to complete. It has the added benefits of improving anaerobic capacity and power output whereas conventional endurance training only positively affects the aerobic energy system. [25]

The Main Source Of Contention- Inclusion Of Aerobics For Body Fat Reduction

Perhaps the most common reason for employing aerobic exercise with strength training is for purposes of reducing body fat. Conventional thinking has long been that aerobics burn significant amounts of calories- enough to create a negative energy deficit that would bring about a reduction in body fat. For this reason, most employ aerobics into their training regime as a way to keep their body weight under control. Considering that aerobic exercise does indeed use fats as an energy source it is easy to see some logic to that approach. However, when compared to high intensity anaerobic training modalities, the idea of aerobics as the best way to lose body fat comes into question. Studies confirm that high intensity training methods create greater post exercise energy expenditure and fat utilization [62,63 64] and favor negative energy and lipid balance to a greater extent than low to moderate intensity aerobic type exercise.[1] That being said you don’t need aerobics to burn fat if the intensity of your anaerobic training is sufficient and if you maintain a sensible diet. (See my article on High Intensity Training & Weight Loss Here)

Are there benefits to aerobics? Absolutely. By no means should this article be construed as a negative hit against such forms of exercise. For many aerobics exercise offers not only numerous health and performance benefits but psychological ones as well. It can be an excellent tool for relieving symptoms of depression and elevating mood. Many people run or do aerobics not so much for a physical effect but for the high that comes with exercise. High intensity training has been shown to elicit similar psychological advantages as well in elevating mood and combating depression [27] but it would be unrealistic to expect everyone to gravitate towards that form of training. Thus, if your goals revolve around maximizing strength and power for athletic performance, the science of the matter would suggest that adding aerobics to a program of weight training could be counterproductive. Those seeking the toned and taut look that comes from building quality lean muscle mass while minimizing body fat levels should also note that aerobics isn’t the only way to shed body fat and that they might be better served avoiding it altogether and instead focus on high intensity training protocols and proper diet to reduce body fat and increase aerobic fitness levels. On the other hand, runners and endurance athletes as a whole would benefit greatly by adding strength training to their exercise programs as it may help maintain normal levels of testosterone. [5]

While some studies have found seemingly contradictory findings regarding concurrent strength and aerobics training, these differences appear mainly to be due to differences in protocols, exercises used, length of the studies and the age and fitness levels of the participants selected. Studies using high intensity strength training as a control however seem to confirm the effects of overtraining as a result of performing both training modalities concurrently as well as a decrease in power generation and strength friendly muscle fiber development. Also of importance is the increased cortisol production observed in those studies of concurrent aerobic and strength training protocols. In two decades of experience as a trainer, I have consistently seen significant increases in muscle mass, strength and power generation in endurance athletes I have worked with when they cease endurance training altogether in the offseason or as a result of injury. However, these increases occurred without any subsequent loss of aerobic fitness capacity when they eventually resumed distance based training. In the end, it is up to you to determine what your goals are and ensure that the program you use helps you attain those goals as opposed to being locked into the idea that aerobic exercise is a universal requirement for everyone.

Celebrity NYC personal trainer Kevin Richardson is an award wining health and fitness writer and the creator of Naturally Intense High Intensity Training and one of the most sought after personal trainers in New York City. Get a copy of his free weight loss e-book here.

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References

1. Marcus EC, Wagner PP, Chiu L. Power Athletes and Distance Training- Physiological and Biomechanical Rationale for Change. Sports Med 2007

2 Chen ZP, Stephens TJ, Murphy S et al. Effect of Exercise on skeletal muscle AMPK signaling in humans. Diabetes 2003

3 Tremblay A, Simoncau JA, Bouchard C. Impact of exercise intensity on energy expenditure, lipid oxidation and body fatness. Int J Obes Relat Metab Disord 2001

4. Chilibeck PD, Bell GJ, Farrar RP, et al. Higher mitochondrial fatty acid oxidation following intermittent verseus continuous endurance exercise training. Can J Physiol Pharmacol 1998

5 Bell GJ, Syrtuik D, Martin TP et al. Effect of concurrent strength and endurance training on skeletal muscle properties and hormone concentrations in humans. Eur J Appl Physiol 2000

6. Hennessy LC, Watson AWS. The interference effects of training for strength and endurance simultaneously. J Strength Cond Res 1994

7. Kraemer WJ, Patton JF, Gordon SE, et al. Compatibility of high intensity training and endurance training on hormonal and skeletal muscle adaptations. J Appl Physiol 1995

8. Dudley GA, Djamil R. Incompatibility of endurance and strength training modes of exercise. J Appl Physiol 1985

9. Taylor J. Basketball: applying time motion data to conditioning. Strength Cond J 2003

10. Wisloff U, Helgerud J, Hoff J. Strength and endurance of elite soccer players. Med Sci Sports Exerc 1998

11. Beham DG, Sale DG. Intended rather than actual movement velocity determines velocity specific training response. J Appl Physiol

12. Hakkinen K, Alen M, Kramer WJ , et al. Neuromuscular adaptations during concurrent strength and endurance training versus strength training. Eur J Appl Physiol 2003

13. Casey A, Constantin-Teodousiu D, Howell Se, et al. Metabolic response of type I and II muscle fibers during repeated bouts of maximal exercise in humans. Am J Physiol 1996

14. Thayer R, Collins J, Noble EG, et al. A decade of aerobic endurance training: histological evidence for fiber type transformation. J Sports Med Phys Fitness 1994

15. Dawson B, Fitzsimons M, Green S, et al, Changes in performance, muscle metabolites, enzymes and fiber types after short sprint training. Euro J Appl Physiol 1998

16. Jacobs I, Esbjornsson M, Sylven C, et al. Sprint training effects on muscle myoglobin, enzymes, fiber types, and blood lactate. Med Sci Sports Exerc 1987

17. Jansson E, Esbjornsson M, Holm I, et al. Increase in the proportion of fast-twitch muscle fibers by sprint training in males. Acta Physiol Scand 1990

18. Bell GJ, Syrotuik D, Socha T, Maclean I, et al. Effect of strength training and concurrent strength and endurance training on strength, testosterone, and cortisol. J Strength Cond Res 1997

19. Kuipers H, Keizer HA. Overtraining in elite athletes: review and directions for the future. Sports Med 1988

20. Smith LL. Tissue trauma: the underlying cause of overtraining syndrome?  J Strength Cond Res 2004

21. Anshel MH, Novak J. Effects of different intensities of fatigue in performing a sport skill requiring explosive muscular effort: a test of the specificity of practice principle. Percept Mot Skills 1989

22. Arnett MG, DeLuccia D, Gilmartin K. Male and female differences and the specificity of fatigue on skill acquisition and transfer performance. Res Q Exerc Sport 2000

23. Williams LR, Daniel-Smith JH, Gunson LK. Specificity of training for motor skill under physical fatigue. Med Sci Sports 1976

24. Dolgener FA,Brooks WB. The effects of interval and continuous training on VO2max and performance in the mile run. J sports Med Phys Fitness 1978

25. Tabata I, Nishimura K, Kouzaki,  M, Hirai Y, Ogita F, Miyachi M, Yamamoto K Effects of moderate-intensity endurance and high-intensity intermittent training on anaerobic capacity and VO2max. Med Sci Sports Exerc. 1996

26. Burgomaster KA, Howarth KR, Phillips SM, Rakobowchuk M, MacDonald MJ, McGee SL, Gibala M. Similar metabolic adaptations during exercise after low volume sprint interval and traditional endurance training in humans. J App Physiol  586: 151-160, 2008

27. Singh NA, Stavrinos TM, Scarbeck Y, Galambos G, Liber C, Singh MA. A randomized controlled trial of high versus low intensity weight training versus general practitioner care for clinical depression in older adults. Journal of Gerontology: Medical Sciences

Top 10 Health & Fitness Articles Of 2011

In 2011 over a quarter of a million people read our blog articles as it has become more and more popular over the past several months. In this posting we take a look at the top ten most popular health and fitness articles posted in 2011. To determine popularity we looked not only at the number of ‘Likes’ and ‘Tweets’ but also factored in the number of readers and reader response. Hopefully some of your favorites made it into the final top ten list and I am sure that you will find a few other gems that you may have missed! Thanks again for the continued support!

Top 10 Health & Fitness Articles of 2011

10. The Anti-Aging Properties Of Weight Training & Resistance Exercise

A detailed look at how our body ages on a cellular  level and how weight training and resistance exercise can play a significant role in maintaining quality of life as you get older. You can read the article in its entirety here.

9. Sweating Has Nothing to Do With Losing Fat

Getting a good sweat is thought of as the key to a good fat burning workout, however sweating has nothing to do with fat loss and is a poor indicator of how much fat you are burning while training or doing any physical activity. Read the article in its entirety here.

8. Tongol Tuna- A Safe Real Food Choice

I started writing about the benefits of tongol tuna several years ago and in this article we go over the problem of mercury in fish and the role of tongol tuna as a lower mercury alternative to traditional albacore tuna. You can read the article in its entirety here.

7. Six Pack Abs- It’s Not What You Do- It’s What & How You Eat

The quest of six pack abdominals has become the Holy Grail for many as the ultimate goal of their diet and exercise program. Unfortunately a surge of exercise products and services have sprung up over the years offering consumers much in the way of false hope by promoting various exercises as the way to a chiseled midsection. As lucrative as these products may be they not only don’t work, but distract us from the reality that a six pack comes from what and how you eat more than what type of exercises you do. You can read the article in its entirety here.

6. Multi-Vitamins & Vitamin Supplements Do More Harm Than Good

Multi-vitamins have long been thought of as a must have for anyone serious about their health. However hundreds of studies show that not only are multi-vitamins unnecessary for a population that is not clinically deficient in any major nutrient, but that they may actually increase the likelihood of certain diseases. If you take multi-vitamins or any vitamin supplement this is an article that you owe it to yourself to read.  You can read the article in its entirety here.

5. The Economics Of Obesity- Why The Food Industry Needs Us to Overeat

One of the biggest problems we face in the fight against obesity and growing diet related problems is the fact that the government plays a key role in supporting and promoting the food industries that make the very foods that we ought to avoid. In this in depth two part article we take a look at how the industry makes us eat more and how important overeating has become for the sustainability of the American economy as we know it. A must read for anyone interested in the behind the scenes machinery that allows corporations to wreak havoc with public health. You can read the article in its entirety here.

4. Can Bread Make You Gain Weight?

There is a common belief that bread will make you gain weight but the truth is that if you eat anything more than you should you’ll put some extra pounds on. In this article we take a look at the history of one of our oldest foods and debunk some of the myths about bread while showing the major differences between what we eat today and the bread that sustained our forefathers. You can read the article in its entirety here.

3. How Do Muscles Get Bigger And Stronger?

While many slave away at the gym in the quest for bigger and stronger muscles, few take the time to understand the mechanisms by which our muscles grow. In this comprehensive piece we take a look at our body’s response to stress, how it translates into improvements in our physiques and our performance and why training less is best. You can read the article in its entirety here.

2. Rethinking The Need For Cardio- Why Aerobics Don’t Work Well For Fat Loss

Aerobic type exercise is without question the most popular fitness activity for those bent on losing weight- however numerous studies and an understanding of the physiology of how our cardiovascular and muscular systems interact show that it isn’t the most effect form of exercise if weight loss is your ultimate goal. You can read the article in its entirety here.

1. Are Protein Shakes Bad For You?

The most popular article of the 2011 is about the now ubiquitous protein shake. While a staple in the dietary regime of almost all gym goers there is yet no real evidence that protein shakes actually help increase muscle mass or improve performance. In fact, evidence suggests that they might not necessarily be a good choice for someone interested in getting into peak shape. You can read the article in its entirety here.

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Celebrity NYC personal trainer Kevin Richardson is the creator of Naturally Intense High Intensity Training and one of the most sought after personal trainers in New York City. Get a copy of his free weight loss e-book here. You can contact Kevin at 1-800-798-8420.

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The Anti-Aging Properties Of Weight Training & Resistance Exercise

As you read this article you, like every other person alive on the planet, are getting older. From the moment we are born, we begin to age but unfortunately, most of us don’t really pay any mind to getting older until we start seeing tangible signs of the passage of time on our body. Thanks to advances in medical technology and improvements in living conditions. people are living longer than ever.  So much so that by the year 2030, there will be more than twice the number of Americans over the age of 65 than there was in the year 2000.[1] Unfortunately, here in the West the very process of aging is looked upon as an illness in dire need of ‘treatment’- a way of thinking based on the fact that for most Americans aging is indeed a narrative of decline. Increased body fat, significant loss of muscle mass and strength to the point of infirmity in addition to the slew of age associated conditions such as cardiovascular disease, diabetes, hypertension and osteoporosis are erroneously seen as an inevitable consequence of growing older. However, studies of older individuals who regularly engaged in weight training and bodybuilding have always challenged the idea that such infirmities come more as a self-fulfilling prophecy as a result of inactivity and poor dietary choices than a fate that we are all destined to suffer.[2] In this article, we will take a look at the physiological aspect of aging and how weight training and resistance exercise can create what gerontologists today term successful aging- namely getting older with a low probability of disease or physical disability, maintaining high cognitive and physical function and having an active engagement with life in your later years.[3,4]

Understanding The Mechanisms Of Aging
So, how exactly does aging occur? We can easily see the results of aging but there are certain biological mechanisms at work that we are often unaware of. The number cells that make up our body are kept at a relatively steady number through the process of mitosis (cells dividing) matched by the number of cells dying. This balance (homeostasis) is necessary for optimal health and body function however this equilibrium cannot be maintained indefinitely. In what is called the Hayflick limit, all animal cells have a limited number of times that they can reproduce. As we get older, senescence sets in- which is a decline in the ability of our bodies’ cells to divide. This usually starts in our early thirties and continues on throughout our lives. One prevailing theory is that the everyday occurrence of cellular reproduction leads to cumulative damage to our DNA and cells begin to die or not function correctly. This process, called apoptosis is actually beneficial as it acts a way of ‘cleaning up’ that benefits the healthy remaining cells. Taken as a whole, aging thus is nothing more than our bodies decline in being able to deal with stress. Maintaining homeostasis becomes more and more difficult until a point is reached where the organism dies.

The Role Of Weight Training In The Prevention of Muscle Wasting

Building muscle however through the use of a well executed weight training program of sufficient intensity is a way of increasing our bodies’ potential response to stress. As we get older, one of the main aspects working against us from being as strong and as built as we were in our younger years is sarcopenia. Sarcopenia which means literally ‘poverty of the flesh’, refers to the loss of skeletal  muscle mass that comes with aging which in turn leads to weakness and frailty. For the average member of the population, as much as 50% of your skeletal muscle mass is lost between the ages of 20 and 90 years resulting in in a corresponding reduction in muscular strength. Such loss of muscle mass is usually associated as well with an increase in overall body fat. However as normal an occurrence this might be for most of us, studies suggest that lack of exercise- or more specifically weight bearing resistance exercise (like weight training) may be one of the overriding causes of sacropenia.[5]

We don’t have to lose such large amounts of muscle mass as we age, but without an active lifestyle that incorporates some form of resistance exercise over the course of time our bodies will indeed fall victim to the syndrome of ‘use it or lose it.’ While it would be absurd to think that weight training can allow you to be strong and muscular as you were in your twenties, preliminary research shows that those who engage in intense weight training over the course of their lifetime are able to demonstrate physical qualities and abilities on par with if not exceeding that of untrained individuals in their twenties while well into their fifth decade of life. With most of our medical anti-aging focus resting on the shoulders of pharmaceutical companies trying to find a pill form solution to the combat the effects of the march of time, comparatively little is invested in researching protocols that are far less potentially lucrative such as weight training. Nevertheless, short term studies thus far do indeed show that resistance exercises like weight training increase the ability of our muscles to synthesize proteins and thus minimizing the advent of skeletal muscle decline over the years. [6,7]

Getting Older- A Detailed Look At The Physiology

As we get older, it is not only our muscles that get significantly weaker without physical activity but also our bones. Increased bone porosity and reduction in bone mass can lead to the debilitating effects of osteoporosis. Which as we know can be both reversed and prevented by the implementation of weight bearing activities such as weight training.[8] (Read my article on how weight training prevents osteoporosis here). There are some aspects however that are beyond our control, as with the advancing years comes a natural decrease in the speed of nerve conduction, reduction in peak cardiovascular ability as well as a decline in kidney and other organ function. As mentioned earlier in an explanation of the Hayflick limit- our cells have a limited number of reproductions- and as you get older the motor units (motoneurons) in your fast twitch muscles begin to die. You don’t immediately notice it, as our bodies have a remarkable system of compensating. Consider that a muscles in  your leg may have 250 motor units with each motor unit having as many as a thousand muscle fibers under its control.

This ratio of motor units to muscle fiber is known as an innervation ratio and in this case would be 1,000 muscle fibers per motoneuron.
Over the course of time, those 250 motor units in your leg muscle may drop by as much as half to 125 by the time you are 70 years old, and you would think that this would make you only half as strong, but it isn’t that straightforward. You see, we lose muscle fibers at a much slower rate than motor units so you would have only lost 10% of the muscle fiber in that leg muscle by the age of 70. However, the remaining 125 motor units sprout new branches to the muscle fibers that have lost their motor units to activate them and do more work than they did before. As a result, there is a higher innervation ratio, in this example it would be let us say 1,500 muscle fibers per motoneuron as our motor units take control of more muscle fibers as a way of helping us retain our strength as we get older.

Our nervous system also slows with the passage of time and so the mechanisms of muscle contraction slows down as well. Despite these natural declines, regular resistance type exercise and an overall active lifestyle can help minimize and offset the effect of these changes in our bodies. The more muscle mass built up over time, the more strength, coordination and motor skills you will have as you get older. A point lost sadly on the millions of women who invest most of their time pursuing aerobic type exercises and lower impact activities like yoga out of a misplaced fear of developing man-sized muscles and thus curtail their involvement in weight training- the very exercises that will help them stay looking and feeling younger as the years go by. (See my article on Should Women Weight Train Like Men)

Hormone Replacement Isn’t Always The Answer
Our hormones also play a role in the reduction of our muscle mass as we get older. Testosterone, growth hormone and insulin-like growth factor (IGF) help our bodies’ build and maintain muscle mass but there is a marked reduction in production as we get older. High intensity weight training has been shown to increase all three hormones [9,10,11] naturally and within standard human parameters. It might sound like a good idea to forgo weight training and instead turn to hormone replacement therapies but research shows that this reduction in hormones may be a key mechanism that allows us to live longer. Mammalian models with reduced growth hormone (GH) and/or IGF-1 appear to live longer[12,13] and while the administration of testosterone replacement therapy for men has become a lucrative and fast growing industry here in the United States, presently available data do not justify the broad use of such hormones for anti-aging purposes.[14,15]

Effects Of A Lifetime Of Weight Lifting On the Aging Process

My inspiration- Kenny Hall pictured in his early seventies

While it is established that there is a natural decline in our bodies from the age of 30 or so due to the processes mentioned above- there are also many examples of individuals who defy the narrative of decline for far longer than one would expect. In 1987, Dr. Fredrick Hatfield- (or Dr. Squat as he is affectionately known) set a world powerlifting record squatting over 1,000 lbs at the age of 45- more than any human being in history had ever successfully lifted in competition. A feat he was able to continue well into his fifties. My good friend and natural bodybuilder Kenny Hall started competing in his twenties and kept on winning titles for the next half a century. His greatest accomplishment was winning the Pro Mr. America in 1969 but he maintained a level of muscle mass and definition that allowed him to easily best other competitors decades younger than he was until he retired in his 70’s so that others would have their chance to win as well.

The science of Gerontology has only just started to pay attention to the amazing examples set by those engaged in a lifetime of weight training and drug free bodybuilding and research reveals that involvement in such activities can ‘create possibilities for people to age positively and reconstruct what aging “normally” means.”[2,16,17,18] Such studies also highlight the self fulfilling prophecy that our society’s acceptance of advancing age as a time of disengagement, dysfunction and disease goes a long way in our not taking action to prevent it from being just that.  As long as we see aging as a downward trajectory of physical and mental deterioration, we are doomed to experience it as such. One of the common perspectives of men and women involved in weight training activities over the course of their lives and who exhibit remarkable physicality into the later sixth decades of life is what was termed a ‘mondadic styled’ body. In short, they focused on who they were and what they were doing as opposed to being influenced by what society expected them to be or the examples of their peers whose aging process tended to follow the narrative of decline that we are so used to hearing. Without turning to hormonal solutions that can often cause more problems than they solve, these individuals centered themselves on following a lifestyle. A lifestyle that allows them to significantly offset the impact of aging and achieve what we are all looking for- twilight years that aren’t defined by disease and disability but by engagement with life on all levels. We don’t need drugs or DeLeon’s fabled fountain of youth, we just need to make certain forms of exercise a part of our lives at all times.

Related Articles-

How Do Muscles Get Bigger & Stronger

How Weight Training Increases Bone Mass

Kevin Richardson is an award winning health and fitness writer, one of the most sought after personal trainers in New York City and creator of Naturally Intense High Intensity Training™. Get a copy of his free weight loss ebook here. If you live in the New York metropolitan area and need help losing weight or taking your body to the next level give Kevin and his team a call at 1-800-798-8420 or click here to get started with 50% off your trial personal training session.

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References:
1. Administration on aging- Dept of Health & Human Services.
2. Phoenix C, Smith B. Telling a (Good) Counterstory of Aging: Natural Bodybuilding Meets The Narrative of Decline. J Gerontol B Psychol Sci Soc Sci (2011
3. Rowe JW, Kahn RL (1987). “Human ageing: usual and successful”. Science 237 (4811): 143–9. doi:10.1126/science.3299702. PMID 3299702.
4. Rowe JW, Kahn RL (1997). “Successful ageing”. Gerontologist 37 (4): 433–40
5 Abate M, Di Iorio A, Di Renzo D, Paganelli R, Saggini R, Abate G (September 2007). “Frailty in the elderly: the physical dimension”. Eura Medicophys 43 (3): 407–15. PMID 17117147.
6. Hasten, Debbie L; Pak-Loduca J, Obert KA, Yarashski KE (2000). “Resistance exercise acutely increases MHC and mixed muscle protein synthesis rates in 78–84 and 23–32 yr olds”. Am J Physiol Endocrinol Metab 278: E620–E626.
7. Yarasheski, Kevin E (2003). “Aging, and Muscle Protein Metabolism”. J Gerontol A Biol Sci Med Sci 58(10): M918-M922.
8. High-intensity resistance training and postmenopausal bone loss: a meta-analysis.Martyn-St James M, Carroll S. Osteoporosis Int. 2006
9. Pak-Shan Leung,1 William J. Aronson,2 Tung H. Ngo,1 Lawrence A. Golding,3 and R. James Barnard. Exercise alters the IGF axis in vivo and increases p53 protein in prostate tumor cells in vitro. TRANSLATIONAL PHYSIOLOGY
10. Zmuda JM, Thompson PD, Winters SJ. Exercise increases serum testosterone and sex hormone-binding globulin levels in older men. Metabolism. 1996 Aug;45(8):935-9.
11. Godfrey RJ, Madgwick Z, Whyte GP. The exercise-induced growth hormone response in athletes.Sports Med. 2003;33(8):599-613.
12.Berryman DE, Christiansen JS, Johannsson G, Thorner MO, Kopchick JJ. Role of the GH/IGF-1 axis in lifespan and healthspan: lessons from animal models.Growth Horm IGF Res. 2008 Dec
13.Carter CS, Ramsey MM, Sonntag WE. A critical analysis of the role of growth hormone and IGF-1 in aging and lifespan.Trends Genet. 2002
14. Heutling D, Lehnert H.[Hormone therapy and anti-aging: is there an indication?].Internist (Berl). 2008 May
15. Kliesch S[Hormone therapy in the aging male. Estrogen, DHEA, melatonin, somatotropin].Urologe A. 2004
16. Dionigi, R. (2008). Competing for life, older people, sport and ageing. Verlag, Germany: VDM Verlag.
17. Grant, B. C. (2001). ‘You’re never too old’: Beliefs about physical activity and playing sport in later life. Ageing and Society
18. Phoenix, C. (2010). Auto-photography in aging studies: Exploring issues of identity construction in mature bodybuilders. Journal of Aging Studies
Zehr P. Becoming Batman- John Hopkins University Press

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Brief High Intensity Training As A Preventative Factor Against Pre-Diabetes

For the last two decades the diabetes rate here in the United States has increased significantly and it continues to rise with no signs whatsoever of those numbers going down anytime soon. According to a recent survey conducted by the Center For Diseases & Control nearly 26 million Americans have diabetes, with 95% of those cases being type 2 diabetes, in which the body gradually loses its ability to use and produce insulin. A number that by no means small, but what is more disturbing is that estimates are that 79 million Americans are prediabetic.  That’s over one third of the entire US population. A number that reaches out and touches all of us- our friends, our families and us individually as well. Being prediabetic means having blood sugar levels that are higher than what ideal levels should be, but not high enough to be clinically diagnosed as being diabetic.[1,2]

Unfortunately, prediabetes increases your risk of developing type 2 diabetes in addition to the risk of cardiovascular disease and stroke.  What experts term as the  ‘Western Style Diet’ has been implicated as the central cause of our increased rates of diabetes[3] in addition to sedentary lifestyles and obesity. Eating better is an important part of the fight against diabetes but equally important is the need to integrate a regular routine of exercise and physical activity.  However given the demands of modern living most cite lack of time as being the primary reason they don’t engage in regular exercise. [4]That being said, infrequent bouts of brief high intensity training routines of 10-15 minutes have been shown to have a positive effect in improving insulin action and thus could be the answer to those without adequate time to train with a predisposition towards diabetes and obesity.[5]

What Is Prediabetes?

As mentioned above, prediabetes usually precedes a full diabetic diagnosis and is characterized by impaired fasting glucose where fasting blood sugar levels are higher than normal but not elevated to the point of a diabetes mellitus classification. Long term, large scale studies have shown that being prediabetic can cause long term damage to the heart and circulatory system and increase your risk of dying from cardiovascular disease even though there isn’t a full diagnosis of diabetes.[6, 7] Unfortunately, for many there are no marked symptoms of prediabtes, unlike diabetes mellitus which while sometimes difficult to identify without clinical testing does at times have some signs such as fatigue, weight gain,  difficulty seeing, slow healing of cuts and wounds as well as tingling or loss of sensation in the extremities. That being said, given the widespread nature of prediabetes, fasting plasma glucose screening is important for everyone over the age of 30 and might be a good idea for younger individuals who are at risk due to lifestyle and or a high incidence of family history with diabetes.

High Intensity Training As A Preventative Factor Against Pre-Diabetes

The key however, aside from maintaining a healthy body weight through proper diet is to also be sure to incorporate exercise into your routine as a way of both preventing and reducing the risks associated with higher blood fasting levels. One of the easiest and most efficient ways to do this is though the implementation of a high intensity training program- which does not require much in the way of time (as little as three workouts of ten to fifteen minutes duration per week) and is a practical solution for todays’ personal time deprived lifestyles. According to a recent study extremely short duration high intensity training significantly improves insulin action in young healthy males. Type 2 diabetes is a very health problem here in the United States and in developed countries- a veritable pandemic affecting millions of children and adults alike. While it has been conclusively established that the risk of developing Type 2 diabetes can be reduced by regular exercise [8]. It is also true that most people find it difficult to consistently follow a routine due to lack of time as conventional exercise guidelines call for at least an hour of aerobic type activity five times a week. The commitment required for such training protocols are beyond the means of most living within the constraints of the very hectic realities of modern life. As many experts in the field have noted, in order for an exercise protocol to as well as a health benefit for the individual, not only should the regime reliably modify key disease risk factors, it must also be plausible to implement.

The Role Of Short High Intensity Training In Improving Insulin Action & Blood Sugar

You don't need to train for hours to improve your blood sugar response if you train at high intensity.

Brief high intensity training workouts have been demonstrated to produce improvements in aerobic function, but it was previously unknown whether high intensity training had the capacity to improve insulin action and hence glycemic control. An important study published in the journal BMC Endocrine Disorders however shows that such brief high intensity training may indeed have a pivotal role as a time saving exercise protocol for the prevention of diabetes. For the study 16 young men in their early twenties underwent a regime of 15 minute high intensity training for two weeks using stationary bicycles. Aerobic performance assessment as well as an oral glucose tolerance test to determine insulin response were administered both before and after the training periods. At the end of the two weeks of high intensity training researchers observed a significant increase in insulin action in addition to an increase in aerobic performance. Researchers concluded that “the efficacy of a high intensity exercise protocol, involving only ~250 kcal of work each week, to substantially improve insulin action in young sedentary subjects is remarkable…This novel time-efficient training paradigm can be used as a strategy to reduce metabolic risk factors in young and middle aged sedentary populations who otherwise would not adhere to time consuming traditional aerobic exercise regimes.”[9]

It’s Not How Long You Train- It’s How Hard You Train

Studies conducted at Arizona State University and Texas University not only confirm the increase in insulin action as a result of high intensity resistance training, but highlight two very important conclusions-

1. Higher intensity multiple set training protocols yielded the greatest treatment effect in improving both fasting glucose and insulin sensitivity.[10]
2. High volume resistance training is not a requirement for improved insulin sensitivity as a result of exercise as individuals performing high intensity low volume exercise have similar improvements in insulin sensitivity as those engaged in higher volume training programs. [11]

Taking this into consideration, a high intensity training protocol is one that many pressed for time should seriously consider. Not only have short intense workouts been demonstrated to improve insulin action but it has also been shown to increase muscle mass, increase endurance and aerobic capacity and decrease body fat better than aerobic exercise and conventional high volume training programs.[12,13,14,15,16,17,18] All the while increasing bone density, improving cardiovascular health and significantly reducing both the incidence and severity of depression.[19,20,21,22]

References: 

 1. Power of Prevention, American College of Endocrinology. Vol. 1, issue 1, January 2009. http://www.powerofprevention.com/POP_magazine_Jan2009_final.pdf/
2.  Jellinger, Paul S. “What You Need to Know about Prediabetes.” Power of Prevention, American College of Endocrinology. Vol. 1, issue 2, May 2009
 3. Wild S, Roglic G, Green A, Sicree R, King H (May 2004). “Global prevalence of diabetes: estimates for 2000 and projections for 2030″. Diabetes Care
 4. Gilba MJ. High-intensity Interval Training: A Time-efficient Strategy for Health Promotion. Current Sports Medicine Reports 2007
5. Babraj JA, Vollaard BJ, Keast C, Guppy FM, Cottrell G, Timmons JA. Extremely short duration high intensity interval training substantially improves insulin action in young healthy males- BMC Endocr Disord. 2009
6. Fontbonne A, Charles MA, Thibult N, Richard JL, Claude JR, Warnet JM, Rosselin GE, Eschwège E. Hyperinsulinaemia as a predictor of coronary heart disease mortality in a healthy population: the Paris Prospective Study, 15-year follow-up. Diabetologia. 1991
7. Barr EL, Zimmet PZ, Welborn TA, et al. (2007). “Risk of cardiovascular and all-cause mortality in individuals with diabetes mellitus, impaired fasting glucose, and impaired glucose tolerance: the Australian Diabetes, Obesity, and Lifestyle Study
8. C. A. Witczak1 and M. Sturek. Exercise prevents diabetes-induced impairment in superficial buffer barrier in porcine coronary smooth muscle. Journal of applied Physiology
 9. Pedersen BK, Saltin B: Evidence for prescribing exercise as therapy in chronic disease. Scand J Med Sci Sports 2006
 10. Black LE, Swan PD, Alvar BA. Effects of intensity and volume on insulin sensitivity during acute bouts of resistance training. J Strength Cond Res. 2010 Apr;24(4):1109-16.
 11. Reed ME, Ben-Ezra V, Biggerstaff KD, Nichols DL. The Effects of Two Bouts of High- and Low-Volume Resistance Exercise on Glucose Tolerance in Normoglycemic Women. J Strength Cond Res. 2011 Dec 8.
12. Hawley JA,  Specificity of training adaptation: time for a rethink? Physiol. 2008
13. Tremblay, A. et al. Impact of exercise intensity on body fatness and skeletal muscle metabolism. Physical Activities Sciences Laboratory, Laval University, Quebec, Canada Metabolism.1994; 43(7): 814-818.
14.  Tabata I, Nishimura K, Kouzaki M, Hirai Y, Ogita F, Miyachi M, Yamamoto K.-Med Sci Sports Exerc. 1996 Oct;28(10):1327-30.Effects of moderate-intensity endurance and high-intensity intermittent training on anaerobic capacity and VO2max.
15. Burgomaster KA, Howarth KR, Phillips SM, Rakobowchuk M, MacDonald MJ, McGee SL, Gibala M. Similar metabolic adaptations during exercise after low volume sprint interval and traditional endurance training in humans.  J Physiol 586: 151-160, 2008
16. Bahr R (1992). “Excess postexercise oxygen consumption–magnitude, mechanisms and practical implications”. Acta Physiologica Scandinavica. Supplementum 605
 17. Bahr R, Høstmark AT, Newsholme EA, Grønnerød O, Sejersted OM (September 1991). “Effect of exercise on recovery changes in plasma levels of FFA, glycerol, glucose and catecholamines”. Acta Physiologica Scandinavica 143
 18. Bielinski R, Schutz Y, Jéquier E (July 1985). “Energy metabolism during the postexercise recovery in man”. The American Journal of Clinical Nutrition 42
 19. High-intensity resistance training and postmenopausal bone loss: a meta-analysis.Martyn-St James M, Carroll S. Osteoporos Int. 2006
 20. Doyne EJ, Ossip-Klein DJ, Bowman ED, Osborn KM, McDougall-Wilson IB, Neimeyer IB. Running Versus Weight Lifting in the Treatment of Depression. Journal of Consulting and Clinical Psychology.
 21. Martinsen EW, Hoffart A, Solberg O. Comparing aerobic and non aerobic forms of exercise in the treatment of clinical depression: a randomized trial. Comprehensive Psychiatry
 22. Singh NA, Stavrinos TM, Scarbeck Y, Galambos G, Liber C, Singh MA. A randomized controlled trial of high versus low intensity weight training versus general practitioner care for clinical depression in older adults. Journal of Gerontology: Medical Sciences

Kevin Richardson is an award winning health and fitness writer, one of the most sought after personal trainers in New York City and creator of Naturally Intense High Intensity Training™. Get a copy of his free weight loss ebook here. If you live in the New York metropolitan area and need help losing weight or taking your body to the next level give Kevin and his team a call at 1-800-798-8420 or click here to get started with 50% off your trial personal training session.

Sign up for our Email Newsletter

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Sleep And Weight Loss- Not Enough Sleep Makes You Gain Weight

In this day and age, not sleeping is seen not only as an admirable trait but as a noble requirement for anyone aspiring towards any degree of financial success. Compared to years past Americans sleep far less than they ever did with twenty percent of the population reportedly getting less than six hours of sleep a night. That’s one in five in the realm of being chronically sleep deprived while the rest of the nation isn’t doing that much better with the number of people reportedly getting less than eight hours of sleep increasing drastically as the years go by. Contrast this with a century ago when the US national average was around 9-10 hours of sleep per night! A dream for most by today’s standards (pardon the pun) as that is far beyond what any average member of the society gets today.  This overall reduction in sleep time unfortunately applies not only to adults, but to children as well.  There are so many more stimuli in our lives that stealthily rob us of our precious time in bed. Television and the internet play a major role in making both children and adult lives stay up longer but our increased work times are also significant. In a sense we have sacrificed sleep for increased productivity. Working more and becoming a nation of robot like machines fueled by coffee and the caffeinated energy drink of the day. What is overlooked in this equation is the effect of sleep deprivation not only on our overall health but as a contributing factor to the increased numbers of overweight American adults and children. Numerous studies have found that not enough sleep can make you gain weight and experience has shown that it can also seriously sabotage your weight loss efforts!

Second only to casual alcohol consumption, the common denominator among my clients who had difficulty losing weight over the past twenty years has been sleep deprivation. Not only was lack of sleep a physiological barrier to them losing weight as easily as others who were eating well and sleeping normally, but it also appeared to be a behavioral obstacle- as those who stayed up longer tended to consume more calories and were more likely to eat more junk food at the end of the day. It is very much a vicious cycle as eating significant amounts of food late at night makes it physically harder for you to fall asleep, affects your sleep quality and reduces how long you can stay asleep.[1] (See our article on Night Eating Syndrome)  In this article we will take a look at the insidious role of sleep deprivation in making us fatter and how the very demands of the modern workplace may be working against your health and your waistline.

Most are sleep deprived during the week and then try to make up for it on weekends- which only makes it easier for you to gain weight.

When sleep deprivation studies on laboratory animals were first carried out researchers confirmed what most of us would think to be true – namely that sleep deprived animals would suffer a decrease in overall body weight over time.2, 3. However numerous epidemiological studies with humans show quite the opposite effect- that humans tend to gain weight as a result of sleep deprivation.[3,4,5,6,7] A explanation of this phenomenon may come as a consequence of human sleep deprivation in the real world occurring because of alterations between periods of restricted sleep followed by periods of increased sleep. A chronic pattern that mirrors our five day work week during which most sleep far less than optimal times followed by weekends where many attempt to make up for sleep lost during the week. A study conducted by researchers at the University of Groningen in the Netherlands set out to model human conditions of chronic sleep restriction by having male rats endure 5 day periods of sleep deprivation followed by a 2 day period of sleep allowance. There was also a control group of rats who were consistently sleep deprived. In the first few weeks there was some loss of body mass in the sleep deprived rats, but in the following weeks there were two incredibly important changes that were observed:

The first was a significant increase in food intake on days that the rats were sleep deprived.

The second finding was an increase in weight gain during the weekends where the rats were allowed to sleep for regular periods of time.

What is fascinating about the weight gain is that the food intake during those days was not notably different from the food intakes of the sleep deprived rats in the control group who lost weight during the period eating the same amount of food.[3]

Sleep Deprivation and Hormones- How Lack Of Sleep Affect Hormones That Make Us Gain Weight

There is without question no shortage of well controlled studies of both humans and animals that underline the fact that the chronic partial sleep loss that has become the benchmark of our times may increase your risk of obesity. Research has shown that there are marked changes in metabolism and endocrine function as a result of sleep deprivation in both adults and children.[4,7]

Sleep restriction plays a major role in affecting us hormonally, namely by:

1. Decreasing glucose tolerance- which not only can lead to weight gain but an increased risk of diabetes and cardiovascular disease [8]
2. Increasing insulin sensitivity- insulin resistance is a precondition to diabetes and is recognized as a contributing factor to obesity and weight gain. Interestingly enough, caffeine used to offset the effects of inadequate sleep also plays a role in increasing insulin resistance as well.[9, 10,11,12]
3. Increased concentrations of the stress hormone cortisol later in the day- which can work to suppress your immune system and increase susceptibility to disease.[13,14] Note however that there is no science to support the popular theory that cortisol causes weight gain- as this is simply another form of misinformation used to sell weight loss products of questionable efficacy.
4. Increased levels of ghrelin- Ghrelin is an important hormone that stimulates our appetite and desire to eat[15] which can in turn lead to overeating and consequent weight gain when concentrations are high.[16] (See my article on how ghrelin affects our appetite here)
5. Decreased levels of leptin- acting contrary to the effects of ghrelin, leptin serves to inhibit our appetite and tell us when we should stop eating.[17] (See my article on the role of leptin in weight gain here)

Fighting Back- Increasing Quantity & Quality of Sleep As An Aid to Weight Loss

You can't drink coffee if you have limited sleep time and want to make the most of it.

Taken as a whole, chronic sleep deprivations creates a perfect storm of hormonal reactions that all contribute to increasing your risk of obesity and making it much harder for you to lose weight and keep it off. As such more and more clinicians are recommending increased sleep time as an intervention to help prevent the onset of obesity and the syndrome of life shortening disease that accompany it. In my practice, individuals with jobs where their working hours were constantly changing always had the lowest amount of weight loss compared to regular sleepers, followed closely as mentioned before by those who slept less than six hours during the work week. It might seem to be a hopeless proposition given the increased number of work hours that our lives today often demand, but it isn’t impossible to get a decent number of hours of sleep if you follow these key rules that I have used quite successfully with my clients over the years.

Strategies for Sleeping Better

1. Restrict internet and television time after 9 pm. Most of us use both television or internet surfing as a way to unwind after a long day- but that very action can do more to rob us of valuable sleep time than help us truly relax. If you don’t have that much time to sleep then read a book to help you catch your breath and relax after work. You won’t be as stimulated and it will be less likely to keep you up.
2. Don’t drink caffeinated drinks. It is better to be sleepy all day and sleep well at night than alert all day and too wired to get decent sleep time at the end of the day. Coffee, energy drinks like Red Bull, and fat burners have no place in the lives of anyone with difficulty sleeping or who has limited time available for sleep. Not only will such drinks interfere with your ability to sleep but with your sleep quality as well. The same applies to alcohol as well- don’t drink it to help you go to sleep as it works to initially make you drowsy and then increases your alertness later on- not exactly a workable formula for a good night’s sleep.
3. Don’t drink fluids immediately before bed. Nothing is worse than having to go to the bathroom multiple times during the night. It cuts into your quality sleep time and drinking right before bed can make you do just that. Always curtail your fluid intake two or three hours before bed so you won’t have to ever get up more than once.
4. Got to bed at the same time ever night if at all possible. If you don’t work a job with shift changes, sleeping the same hours every day can go a long way in increasing your quality of sleep and the likelihood that you will fall asleep.

How much sleep exactly do you need? It is a very individual requirement; much like food intake and it depends on the person and their activities. Eight hours is usually quoted as the standard for most, but others may need more or less depending on how they feel. The key is that you should be able to awaken refreshed in the morning at a regular hour without the need for an alarm. If you can’t do that or are excessively groggy and feel that you can’t function first thing in the morning without coffee or a pick me up of some sort- you really don’t need the coffee. What you need is more sleep. If your sleep problems persist however you may need to seek professional help, as inadequate sleep can be very much hazardous to your health.

References:

1.Stunkard A, Allison K., Lundgren J. Issues for DSM-V: Night Eating Syndrome- Am J Psychiatry 165:424, April 2008

2. CA Everson, Functional consequences of sustained sleep deprivation in the rat, Behavioral Brain Research 1995

3. Barf RP, Desprez T, Meerlo P,  Scheurink AJ. Increased food intake and changes in metabolic hormones in response to chronic sleep restriction alternated with short periods of sleep allowance. Am J Physiol Regul Integr Comp Physiol. 2011

4. Taheri S, Lin L, Austin D, Young T, Mignot E (December 2004). “Short Sleep Duration Is Associated with Reduced Leptin, Elevated Ghrelin, and Increased Body Mass Index”.

5. Lyytikäinen P, Rahkonen O, Lahelma E, Lallukka T. Association of sleep duration with weight and weight gain: a prospective follow-up study. J Sleep Res. 2011

6. Nielsen LS, Danielsen KV, Sørensen TI. Short sleep duration as a possible cause of obesity: critical analysis of the epidemiological evidence. Obes Rev. 2011

7 Leproult R, Van Cauter E.Role of sleep and sleep loss in hormonal release and metabolism.Endocr Dev. 2010

8. Barr EL, Zimmet PZ, Welborn TA, et al. (2007). “Risk of cardiovascular and all-cause mortality in individuals with diabetes mellitus, impaired fasting glucose, and impaired glucose tolerance: the Australian Diabetes, Obesity, and Lifestyle Study

9. Graham, TE; Sathasivam, P; Rowland, M; Marko, N; Greer, F; Battram, D (2001). “Caffeine ingestion elevates plasma insulin response in humans during an oral glucose tolerance test”. Canadian journal of physiology and pharmacology

10. Keijzers, GB; De Galan, BE; Tack, CJ; Smits, P (2002). “Caffeine can decrease insulin sensitivity in humans”. Diabetes care

11. Petrie, HJ; Chown, SE; Belfie, LM; Duncan, AM; McLaren, DH; Conquer, JA; Graham, TE (2004). “Caffeine ingestion increases the insulin response to an oral-glucose-tolerance test in obese men before and after weight loss”. The American journal of clinical nutrition

12. Akiba, T; Yaguchi, K; Tsutsumi, K; Nishioka, T; Koyama, I; Nomura, M; Yokogawa, K; Moritani, S et al. (2004). “Inhibitory mechanism of caffeine on insulin-stimulated glucose uptake in adipose cells”. Biochemical pharmacology

13. Palacios R., Sugawara I. (1982). “Hydrocortisone abrogates proliferation of T cells in autologous mixed lymphocyte reaction by rendering the interleukin-2 Producer T cells unresponsive to interleukin-1 and unable to synthesize the T-cell growth factor”. Scand J Immunol

14. Besedovsky, H.O.; Del Rey, A.; Sorkin, E. (1984) “Integration of Activated Immune Cell Products in Immune Endocrine Feedback Circuits.” p. 200 in Leukocytes and Host Defense Vol. 5

15.Inui A, Asakawa A, Bowers CY, et al. (2004). “Ghrelin, appetite, and gastric motility: the emerging role of the stomach as an endocrine organ”. FASEB J. 18 (3): 439–56. doi:10.1096/fj.03-0641rev. PMID 15003990.

16. Castañeda TR, Tong J, Datta R, Culler M, Tschöp MH. (2010). “Ghrelin in the regulation of body weight and metabolism”. Front Neuroendocrinol.

17. Brennan AM, Mantzoros CS (June 2006). “Drug Insight: the role of leptin in human physiology and pathophysiology–emerging clinical applications”. Nat Clin Pract Endocrinol Metab
Kevin Richardson is an award winning health and fitness writer, one of the most sought after personal trainers in New York City and creator of Naturally Intense High Intensity Training™. Get a copy of his free weight loss ebook here. If you live in the New York metropolitan area and need help losing weight or taking your body to the next level give Kevin and his team a call at 1-800-798-8420 or click here to get started with 50% off your trial personal training session.

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