Is Your Exercise Routine Lacking Purpose?

October 6th, 2010

It’s common knowledge that regular exercise is an important part of promoting good health. However, many people shortchange themselves by following an exercise program without putting much thought into what they’re doing or why they’re doing it. This typically results in the benefits of the program being poorly aligned with the individual’s needs and goals, and in some cases, this can do more harm than good.

It goes without saying that most of us make important decisions through a process of specific and deliberate reasoning. Because exercise has a significant influence on health, and because this influence can sometimes be negative, choices relating to exercise deserve the same level of discretion. However, it’s common for people to invest their time, effort, and health into an exercise program without evaluating how appropriate it is for their needs. This greatly reduces the value they’ll gain from their effort.

Why it’s Important to Exercise Intelligently

Many people run mile after mile or spend hour after hour pounding away on a cardio machine each week simply to burn calories or satisfy the general recommendation to exercise regularly. Likewise, it’s become nearly as common for people to lift weights or use resistance training machines to develop or tone muscle. In each of these cases, it’s usually appearance based goals that provide the motivation to exercise, and it’s generally assumed that health and function related benefits will automatically follow. However, because the reasoning behind this assumption is completely backwards, such benefits are far from automatic.

Exercise has a significant influence on physiological function long before changes in appearance can be easily noticed. For example, improvements in the strength and endurance of a muscle must occur prior to a noticeable increase in its size, and improvements in cardiovascular function will begin to occur weeks before exercise alone will have a noticeable impact on weight loss. As such, it’s impossible to alter appearance through exercise without causing physiological adaptations in the process, and it would be unwise to assume that these adaptations are always desirable. Furthermore, it would be wasteful and potentially harmful to endure the physical burden of strenuous training when the adaptations that result are of little value. The average person wanting to lose weight or improve cardiovascular health certainly doesn’t need to develop the aerobic capacity of an endurance athlete to achieve such goals, but many people exercise as if they do.

Those who exercise to alter their appearance or achieve other secondary benefits tend to neglect the more important exercise principles that promote good health and function. Unfortunately, doing so can often have more of a negative impact on quality of life than a positive one, and when this is the case, the secondary benefits that are gained rarely justify the pain and dysfunction that may accompany them. While there’s nothing wrong with exercising to improve appearance, it makes much more sense to pursue such a goal with an approach that emphasizes good health and function as higher priorities.

The Dark Side of Exercise

There’s no doubt that it can be very beneficial to exercise on a regular basis. Doing so has been shown to improve mood and cognitive function, reduce fatigue, improve physical function, and help prevent disease.1 In general, exercise has a tremendous potential to improve quality of life, but when appearance and other secondary benefits are a higher priority than health and function, exercise can have the opposite effect. In many cases, this is because the desire for rapid and dramatic results overshadows sound exercise principles.

Weight loss is an excellent example. The excessive amount of higher intensity aerobic exercise that people commonly do just to burn calories puts a considerable amount of physiological burden on the body. Anyone who exercises like this on a regular basis is likely to compromise their health by consistently exceeding their capacity to recover, especially if they’re under stress, not eating well, or not getting enough sleep, all of which are common characteristics of modern life. Over time, this often leads to chronic symptoms such as fatigue, anxiety, depression, and irritability that can take months to recover from.2,3 Any other form of moderate to high intensity exercise, especially resistance training, can also have this effect when done too frequently.

Training to improve appearance through an increase in muscle size is another great example. People who do this tend to focus most of their effort on the muscles that they think will have the greatest impact on their appearance. In the process, they usually train the opposing muscles much less frequently or don’t train them at all. This creates imbalances in strength and flexibility that can cause pain, limit function, and increase the risk of injury.4 Other forms of exercise that repetitively work opposing muscle groups in an uneven manner can also cause imbalances. This is especially the case with aerobic exercise because of it’s repetitive nature.

Most forms of exercise cause low level tissue damage5-7 as well as other forms of physiological stress such as oxidative and free radical damage,8,9 and the more strenuously and frequently one exercises, the more this applies. Although this damage and stress is much of what provokes the body to repair itself and become more resilient and fit, it can also accelerate the aging process10 and increase the risk of injury.5 Therefore, there’s a fine line between exercising to improve health, function, and general wellness and overexercising to the extent of accelerating the aging process and inviting chronic pain. If you’re going to burden your body with strenuous exercise, you should be sure that there’s a justifiable purpose behind it, and it would be in your best interest to structure your training and lifestyle in a way that minimizes the potential for undesirable effects.

Burning Calories or Burning Out?

Burning calories to lose weight is one of the most common reasons why people overexercise. As I just explained, this approach can be unhealthy, and the extent of direct fitness improvements that result are generally of little use or value to the average person. Diet is a much more important factor for weight loss,11 and based on this, exercising excessively to burn calories is nothing more than a compensation for poor dietary choices. This is a case of one health compromising habit being compensated for by another. It increases the potential for undesirable effects and makes it a questionable approach, especially since it doesn’t address the primary cause of the problem. Based on this, I think weight loss alone is very poor justification for a high volume of intense exercise. This is one of the reasons why I’m not a fan of programs like the P90X that prescribe an arguably excessive volume of exercise primarily to increase energy expenditure.

In my opinion, those who doubt the effectiveness of proper diet as the primary focus of a weight loss program either don’t understand what a truly healthy diet is or simply aren’t dedicated enough to make the necessary changes. Contrary to what most people tend to think, following a healthy diet with an intent to lose weight doesn’t imply the need to obsessively count calories. In fact, I think calorie counting is a flawed approach that’s used as another way to compensate for poor food choices. What I consider to be a truly healthy diet is one that’s well rounded and based primarily on whole foods such as meat, fish, fruit, vegetables, nuts, and seeds. Following such a diet provides the nutrients needed to support optimal health, makes it much more difficult to overeat, and therefore eliminates the need to obsess over daily calorie intake. This is the natural and healthy way to lose weight and keep it off. Exercise, ideally for other more important purposes than simply burning calories, is merely a bonus that will facilitate the process.

Misconceptions About Metabolism

Metabolism is commonly discussed in association with exercise and weight loss, but it often seems to be poorly understood. Although it’s defined as the sum of all chemical reactions that occur in the body,12 most people perceive it as more of a calorie burning potential, and as such, consider a “fast” metabolism to be desirable.

Given the energy demands imposed by exercise, metabolic rate can increase dramatically during an exercise session. Depending on the intensity and type of exercise, metabolic rate can even remain elevated long after activity has ended. This is due to the tissue repair, energy replenishment, and other physiological adaptations that often occur in response to strenuous physical activity.13-16 Metabolic rate can even be increased on a more permanent basis by any type of exercise that increases lean body mass.17,18 However, although these alterations in metabolic rate result in more energy expenditure at rest, this may not be as desirable as it seems. Despite some exceptions for certain species, an increased rate of metabolism has been associated with a shorter lifespan.19,20 Much of this association is believed to be a result of an increase in free radical and oxidative damage, both of which can be caused by exercise and other forms of strenuous physical activity.19,10

Use It or Lose It but Don’t Overdo It

Based on the potential for excessive exercise to increase metabolism and cause free radical and oxidative damage, it can be argued that the more one exercises, the more likely it is that they’ll age more rapidly. However, not exercising enough can be a serious problem as well. It’s been clearly established that insufficient exercise can lead to an accelerated decline in health and even result in premature death.21,22 As such, it’s clearly important to exercise regularly, but if you choose to follow a strenuous exercise program that exceeds the demands of what’s necessary to promote optimal health, the decision should be supported by a meaningful purpose that justifies the additional physiological burden. In addition, training should be planned intelligently to minimize unnecessary burden, and excellent lifestyle habits should be followed closely to improve capacity and recovery.

What About Athletes and Sports?

Those who try to justify their excessive exercise habits based on the tremendous amount of wear and tear that athletes expose their bodies to are failing to appreciate an important point. The opportunity to compete in a sport is something that most athletes value deeply, and as a result, it’s often a valuable source of fulfillment for them. In contrast, anyone who trains with the intensity or volume of an athlete just to burn calories is wearing down their body and getting little value in return, especially since focusing primarily on diet is a much more sensible and reliable way to lose weight. In addition, even athletes need to intelligently plan their training and competitive schedules to minimize any unnecessary physiological burden. In fact, this is critical because it reduces their risk of injury and allows them to train for the variety of fitness and skill requirements of their sport without exceeding their individual capacities. The athletes who don’t appreciate this are much more likely to become injured or fatigued and have a much less rewarding experience with competition.

Many people who dislike gyms and regimented exercise programs prefer to stay active by participating in sports. They rely on the spontaneity and competition of sports to keep them motivated. Although this is perfectly reasonable and is certainly better than not exercising at all, there are some disadvantages to consider. As I already mentioned, playing a sport can and usually does expose the body to a significant amount of physical stress. The dynamic and explosive nature of most sports greatly increases the risk for injury, and anyone who competes without preparing themselves for this risk is much more likely to encounter problems that nullify many of the benefits of staying active. For example, most sports involve jumping which can expose bones, joints, muscles, and connective tissue to forces as great as 10 times body weight.23 This much force is an obvious risk for someone who’s not conditioned for it, especially if they’re overweight or have a history of lower body injuries. I’m definitely not trying to discourage people from participating in sports, but am instead suggesting that anyone who chooses to do so should consider themselves an athlete and prepare as such. In other words, be fit for your sport instead of using your sport to be fit.

Tennis is one of the more popular choices for adults looking to stay active by playing a sport. It’s also an excellent example of why it’s important to be physically prepared. As an avid tennis player, I’ve seen a lot of recreational players incur serious injuries and I know many players who wear one or more braces or straps to deal with chronic pain. The incidence of tennis injuries has been shown to be as high as 3 per player per year and includes a variety of debilitating problems such as tendinitis, torn muscle and connective tissue, and stress fractures. These injuries also tend to occur in critical areas of the body such as the ankles, knees, lower back, shoulder, elbows, and wrists.24 Tennis even has a common form of elbow tendinitis named after it. The many adults who’ve damaged their bodies by using tennis or any other sport as an alternative to structured exercise are likely to agree that it’s wise for recreational and serious athletes alike to be prepared for the physical demands of their sport.

A Healthful and Intelligent Approach to Exercise

The most intelligent, effective, and healthful approach to exercise is to focus on specific benefits relating to health and function that are closely related to your needs and goals. Beyond the common goals of burning calories, building muscle, and improving general health, few people consider how they can benefit from exercise more specifically. It’s worth investing some thought into this because proper planning can make an exercise program much more effective, and in turn, lead to much greater improvements in quality of life. For example, someone who suffers from joint pain and limited function would be much better served by a strength and mobility program that’s focused on solving their problems than general aerobic exercise. This is not to say that aerobic exercise wouldn’t have a place in their program, but rather that it shouldn’t necessarily be the primary focus. In contrast, more of a focus on aerobic exercise would be a better choice for someone who easily becomes winded from walking a flight of stairs or performing basic daily tasks.

With proper planning, the body is spared from excessive burden, time is saved, and the invested effort delivers results that are more meaningful. Planning also makes it easier to address multiple aspects of fitness, and in turn, promote a well rounded state of physical wellness that includes the strength, range of motion, and endurance needed to perform daily activities with minimal discomfort and risk of injury. This is particularly important for both serious and recreational athletes due to the additional demands put on their bodies, and it’s even more important for older individuals who are losing the ability to perform basic functions such as climbing stairs or getting out of a chair.

Guidelines for Basic Fitness Goals

It’s pretty obvious that weight loss is the most common reason why people exercise, or at least why they exercise as much as they do. As I previously suggested, weight loss shouldn’t be the primary focus of an exercise program. The influence that exercise has on weight loss should be regarded as a secondary benefit, and as such, anyone looking to lose weight should focus their exercise program on other goals that are more specific to fitness and physical function.

Heart disease is the leading cause of death in the United States, and approximately every minute, an American dies from a heart related complication.25 Aerobic exercise has been shown to improve cardiovascular function, and in turn, help prevent heart disease.26,27 As such, improving or maintaining cardiovascular health is an excellent fitness goal for everyone, and as I already said, this doesn’t require the rigors of training like an endurance athlete. A simple and appropriate guideline to achieve this goal is to perform aerobic exercise 2 to 5 times per week for a half hour or more at an intensity of about 50% to 70% of maximum heart rate,28-30 or the highest intensity that allows for conversation with little to no difficulty. The lower end of this frequency applies to those who engage in other physical activities, and the upper end of the range is for those who don’t. People who are more adventurous and looking for a little more intensity can substitute two days of this steady state aerobic exercise with a day or two of high intensity interval training. Although this type of training puts a significant demand on the body, it also offers additional physiological benefits that can help promote optimal health if not overdone.31 It can also provide even greater cardiovascular benefits than steady state aerobic exercise alone.32

Although it’s a goal that’s not nearly as common as improving appearance or performance, maintaining and promoting a full range of pain free movement should be a top priority for everyone. This is especially the case for people who aren’t very active. Strength and flexibility naturally decline with age, particularly in those who are less active. Over time, this decline can lead to limitations in physical function and be the root cause of chronic pain.1,33-36,49 Bone density also decreases with age, especially in the absence of weight bearing forces.37-39 Strength training and stretching can help to prevent and reverse age related declines in strength, flexibility, and bone density1,40-44,49 and should therefore be priorities for anyone who wants to maintain healthy and strong bones along with the ability to easily perform basic movements through a full and pain free range of motion. 30 to 45 minutes of strength training done 2 to 3 times per week and stretching each major muscle group at least 2 times per week is more than adequate to meet these goals.28-30 Although it’s not necessary to workout at a gym or lift heavy weights, it’s best to at least include multijoint lower body exercises such as squat, deadlift, or lunge based movements with an emphasis on proper technique.

Regardless of what your training goals are, it’s important to maintain balance. The first aspect of this is to maintain a balance across different areas of fitness. For example, you don’t want to be very strong but have such poor aerobic fitness that you’re winded after walking up a flight of stairs. With this in mind, it’s important to periodically vary the focus of your training, and you can do this by emphasizing one type of training while still including a minimal amount of other types of training for maintenance. For example, a well rounded exercise routine should include strength training, cardiovascular training, and flexibility training while emphasizing one of these areas but not completely neglecting the others. The second aspect of balance is to ensure that the exercises you choose collectively promote a balance of strength and flexibility around joints and between opposing major muscle groups. Failure to do this can lead to poor posture and an increased risk for pain and injury.4,45-48

A Greater Quality of Life

The key thing to remember about exercise is that regardless of one’s specific goals, the ultimate goal is to improve quality of life, or to at least prevent it from declining. Consider the innate ability of a baby to learn and utilize the full squat position. This is a basic human movement that many adults lose the ability to perform as early as their 20s or 30s. Over time, it can progress to the level of not being able to get up from a chair or climb a flight of stairs without pain and difficulty. Similar trends of avoidable degeneration prevent people from participating in activities they enjoy and can even make it excessively difficult to perform basic functions such as walking. This can clearly have a significantly negative impact on quality of life. Exercising in a random and unplanned fashion is unlikely to prevent such problems or promote desired improvements nearly as well as a fitness program designed with a specific purpose in mind.

Also remember that in conjunction with a truly healthy diet and lifestyle, the guidelines discussed here are more than adequate to support and facilitate weight loss. The wear and tear of following a high volume exercise program with the primary intention of burning calories can actually accelerate the physical limitations just described, and in turn, lessen one’s quality of life instead of improving it.

Next time you exercise, ask yourself how the particular activity that you’re doing relates to your goals and needs and if it’s the most appropriate and effective way to pursue such improvements. If you’re not sure how exercise can improve your life, then maybe it’s time to give this some thought. By putting more effort into identifying the benefits of exercise that specifically relate to your goals and needs, and by planning your exercise routine accordingly, your quality of life is likely to improve by a much larger margin.

[1. Chodzko-Zajko WJ, Proctor DN, Singh MA, Minson CT, Nigg CR, Salem GJ, Skinner JS. "Exercise and Physical Activity for Older Adults." Medicine & Science in Sports & Exercise. 2009. 41:7.]
[2. Budgett R. "Fatigue and underperformance in athletes: the overtraining syndrome." British Journal of Sports Medicine. 1998. 32:107-110.]
[3. Budgett R. "Overtraining syndrome." British Journal of Sports Medicine. 1990. 24:231-236.]
[4. Comerford MJ, Mottram SL, "Movement and stability dysfunction - contemporary developments." Manual Therapy. 2001. 6(1):15-26.]
[5. Gibbon WW, Cooper JR, Radcliffe GS. "Sonographic incidence of tendon microtears on athletes with chronic Achilles tendinosis." British Journal of Sports Medicine. 1999. 33:129-130.]
[6. Stupka N, Tarnopolsky MA, Yardley NJ, Phillips SM. "Cellular adaptation to repeated eccentric exercise-induced damage." Journal of Applied Physiology. 2001. 91(4):1669-1678.]
[7. Proske U, Morgan DL. "Muscle damage from eccentric exercise: mechanism, mechanical signs, adaptation and clinical applications." The Journal of Physiology. 2001. 537:333-345.]
[8. Ji L. "Oxidative stress during exercise: implication of antioxidant nutrients." Free Radical Biology and Medicine. 1995. 18:1079-1086.]
[9. Clarkson PM, Thompson HS. "Antioxidants: what role do they play in physical activity and health?." The American Journal of Clinical Nutrition. 2000. 72(2):637S-646S.]
[10. Beckman KB, Ames BN. "The free radical theory of aging matures." Physiological Reviews. 1998. 78(2):547-581.]
[11. Miller WC, Koceja DM, Hamilton EJ. "A meta-analysis of the past 25 years of weight loss research using diet, exercise or diet plus exercise intervention." International Journal of Obesity. 1997. 21:941-947.]
[12. Tortora GJ, Derrickson BH. "Principles of Anatomy and Physiology." 2008.]
[13. Dolezal BA, Potteiger JA, Jacobsen DJ, Benedict SH. "Muscle damage and resting metabolic rate after acute resistance exercise with an eccentric overload." Medicine & Science in Sports & Exercise. 2000. 32(7):1202-1207.]
[14. Bersheim E, Bahr R. "Effect of Exercise Intensity, Duration and Mode on Post-Exercise Oxygen Consumption." Sports Medicine. 33(14):1037-1060.]
[15. Schuenke MD, Mikat RP, McBride JM. "Effect of an acute period of resistance exercise on excess post-exercise oxygen consumption: implications for body mass management." European Journal of Applied Physiology. 2002:86:411-417.]
[16. Campbell WW, Crim MC, Young RV, Evans WJ. "Increased energy requirements and changes in body composition with resistance training in older adults.." The American Journal of Clinical Nutrition. 1994. 60:167-175.]
[17. Cunningham JJ. "A reanalysis of the factors influencing basal metabolic rate in normal adults." The American Journal of Clinical Nutrition. 1980. 33:2372-2374.]
[18. Weinsier RL, Schulz Y, Bracco D. "Reexamination of the relationship of resting metabolic rate to fat-free mass and to the metabolically active components of fat-free mass in humans." The American Journal of Clinical Nutrition. 1992. 55:790-794.]
[19. Speakman JR. "Body size, energy metabolism and lifespan. Journal of Experimental Biology. 2005. 208:1717-1730.]
[20. Van Voorhies WA. Metabolism and lifespan. Experimental Gerontology. 2001. 36:55-64.]
[21. Blair SN, Brodney S. "Effects of physical inactivity and obesity on morbidity and mortality: current evidence and research issues." Medicine & Science in Sports & Exercise. 1999. 31(11):S646-S662.]
[22. Simonsick EM, Lafferty ME, Phillips CL, Mendes de Lean CF, Kasl SV, Seeman TE, Fillenbaum G, Hebert P, Lemke JH. "Risk Due to Inactivity in Physically Capable Older Adults." American Journal of Public Health. 1993. 83:1443-1450.]
[23. McNair PJ, Prapavessis H. <"a href="" target="_blank" rel="nofollow">Normative Data of Vertical Ground Reaction Forces During Landing from a Jump. Journal of Science and Medicine in Sport. 1999. 2(1):86-88.]
[24. Pluim BM, STaal JB, Windler GE, Jayanthi N. "Tennis injuries: occurrence, aetiology, and prevention. British Journal of Sports Medicine. 2006. 40:415-423.]
[25. Lloyd-Jones D, Adams R, Carnethon M, De Simone G, Ferguson B, Flegal K, Ford E, Furie K, Go A, Greenlund K, Haase N, Hailpern S, Ho M, Howard V, Kissela B, Kittner S, Lackland D, Lisabeth L, Marelli A, McDermott M, Meigs J, Mozaffarian D, Nichol Graham, O'Donnell C, Roger V, Rosamond W, Sacco R, Sorlie P, Stafford R, Steinberger J, Thom T, Wasserthiel-Smoller S, Wong N, Wylie-Rosett J, Hong Y. "Heart Disease and Stroke Statistics - 2009 Update." Circulation. 2009. 119:e21-e181.]
[26. Williams PT. "Physical fitness and activity as separate heart disease risk factors: a meta-analysis." Medicine & Science in Sports & Exercise. 2001. 33(5):754-761.]
[27. Do Lee C, Blair SN, Jackson AS. "Cardiorespiratory fitness, body composition, and all-cause and cardiovascular disease mortality in men." American Journal of Clinical Nutrition. 1999. 69(3):373-380.]
[28. Fletcher GF, Balady G, Blair SN, Blumenthal J, Caspersen C, Chaitman B, Epstein S, Sivarajan Froelicher ES, Froelicher VF, Pina IL, Pollock ML. "Statement on Exercise: Benefits and Recommendations for Physical Activity Programs for All Americans." Circulation. 1996. 94:857-862.]
[29. Pollock ML, Gaesser GA, Butcher JD, Despres J, Dishman RK, Franklin BA, Garber CE. "ACSM Position Stand: The Recommended Quantity and Quality of Exercise for Developing and Maintaining Cardiorespiratory and Muscular Fitness and Flexibility in Healthy Adults." Medicine & Science in Sports & Exercise. 1998. 30(6):975-991.]
[30. Haskell WL, Lee I, Pate RR, Powell KE, Blair SN, Franklin BA, Macera CA, Heath GW, Thompson PD, Bauman A. "Physical Activity and Public Health: Updated Recommendation for Adults From the American College of Sports Medicine and the American Heart Association." Circulation. 2007. 116:1081-1093.]
[31. Schoenfeld B, Dawes J. "High-Intensity Interval Training: Applications for General Fitness Training." Strength and Conditioning Journal. 2009. 31(6):44-46.]
[32. Wisloff U, Stoylen A, Loennechen JP, Bruvold M, Rognmo O, Haram PM, Tjonna AE, Helgerud J, Slordahl SA, Lee SJ, Fidem V, Bye A, Smith GL, Najjar SM, Ellingsen O, Skjaerpe T. "Superior Cardiovascular Effect of Aerobic Interval Training Versus Moderate Continuous Training in Heart Failure Patients." Circulation. 2007. 115:3086-3094.]
[33. Buckwalter JA, Woo SL, Goldberg VM, Hadley EC, Booth F, Oegema TR, Eyre DR. "Soft-tissue aging and musculoskeletal function." The Journal of Bone & Joint Surgery. 1993. 75:1533-1548.]
[34. Bell RD, Hoshizaki TB. "Relationships of age and sex with range of motion of seventeen joint actions in humans." Canadian Journal of Applied Sport Sciences. 1981. 6(4):202-206.]
[35. Janssen I, Heymsfield SB, Ross R. "Low Relative Skeletal Muscle Mass (Sarcopenia) in Older Persons Is Associated with Function Impairment and Physical Disability." Journal of the American Geriatrics Society. 2002. 50(5):889-896.]
[36. Doherty TJ. "InvitedReview: Aging and sarcopenia." Journal of Applied Physiology. 2003. 95:1717-1727.]
[37. Wishart JM, Need AO, Horowitz M, Morris A, Nordin BEC. "Effect of age on bone density and bone turnover in men." Clinical Endocrinology. 1995. 42(2):141-146.]
[38. Steiger P, Cummings SR. "Age-related decrements in bone mineral density in women over 65." Journal of Bone and Mineral Research. 1992. 7(6):625-632.]
[39. Chow R, Harrison JE, Notarius C. "Effect of two randomised exercise programmes on bone mass of healthy postmenopausal women." British Medical Journal. 1987. 295:1441-1444.]
[40. Latham NK, Bennett DA, Stretton CM, Anderson CS. "Systematic Review of Progressive Resistance Strength Training in Older Adults." Journal of Gerontology. 2004. 59A(1):48-61.]
[41. Seguin R, Nelson ME. "The benefits of strength training for older adults." American Journal of Preventative medicine. 2003. 25(3):141-149.]
[42. Nelson ME, Fiatarone MA, Morganti CM, Trice I, Greenberg RA, Evans WJ. "Effects of High-Intensity Strength Training on Multiple Risk Factors for Osteporotic Fractures." Journal of the American Medical Association. 1994. 272(24):1909-1914.]
[43. Menkes A, Mazel S, Redmond A, Koffler K, Libanati CR, Gundberg CM, Zizic TM, Hagberg JM, Pratley RE, Hurley BF. "Strength training increases regional bone mineral desnity and bone remodeling in middle-aged and older men." Journal of Applied Physiology. 1993. 74(5):2478-2484.]
[44. Feland JB, Myrer JW, Schulthies SS, Fellingham G, Measom GW. "The Effect of Duration of Stretching of the Hamstring Muscle Group for Increasing Range of Motion in People Aged 65 Years or Older." Journal of the American Physical Therapy Association. 2001. 81(5):1110-1117.]
[45. Sahrmann SA. "Does Postural Assessment Contribute to Patient Care?" Journal of Orthopaedic & Sports Physical Therapy. 2002. 32(8):376-379.]
[46. Weigner AW, Watts RL. "Elastic properties of muscles measured at the elbow in man: I. normal controls." Journal of Neurology, Neurosurgery, and Psyciatry. 1986. 49:1171-1176.]
[47. Chleboun GS, Howell JN, Conatser RR, Giesey JJ. "The relationship between elbow flexor volume and angular stiffness at the elbow." Clinical Biomechanics. 1997. 12(6):383-392.]
[48. Borstad JD. "Resting Position Variables at the Shoulder: Evidence to Support a Posture-Impairment Association." Physical Therapy. 2006. 86(4):549-557.]
[49. Evans WJ, Campbell WW. "Sarcopenia and Age-Related Changes in Body Composition and Functional Capacity." Journal of Nutrition. 1993. 123:465-468.]

Stay informed of new articles by email!