Friday, March 23, 2012
Use It or Lose It: The Price of Inactivity
We all know we should exercise. It feels good during and we feel even better after. We know it burns calories and that our bodies were meant to be used. But all too many of us are sedentary; it just the result of modern life. One result, combined with eating too much, is that one third are overweight and one third are frankly obese. And many of us believe that as we age we will just naturally loose muscle mass and strength. It turns out that is just not correct. We can indeed preserve muscle mass and strength.
A really well trained athlete has little fat in or around his or her muscles. But a person that does not exercise sees his muscles wither and fat take up the space. That is the obvious conclusion from the images shown below.
More and more Americans are living into what used to be called “old age.” With older age often comes various illnesses, many of them chronic such as diabetes, heart failure or cancer. But these chronic illnesses are often preventable with a good diet and moderate exercise. So to is the “sarcopenia” or muscle loss that comes with aging in a sedentary person.
Wroblewski and colleagues at the University of Pittsburgh evaluated persistent exercise over the years. Their study was reported in The Physician and Sports Medicine journal, September, 2011 and sent to me by Frank Jannotta of Harbor Physical Therapy.
Five men and 5 women were recruited in each 10-year age category (40–49 years, 50–59 years, 60–69 years, and ≥ 70 years). Each was an avid exerciser. They were evaluated for their health history, exercise patterns, body composition using the “Bod Pod” and MRI scans of the thighs. The researchers found that despite the age differences, these individuals did not have a significantly different amount of intramuscular adipose tissue; their body fat, BMI, fat mass and muscle mass were all similar. Clearly, continued exercising into the 70’s maintained muscle mass in these individuals.
Here are three images taken by MRI scanning, i.e., a cross sectional picture. They are of the upper leg to show the quadriceps muscle, the large muscle on the front of the thigh that allows us to lift our leg and bend our knee when we walk or run.
The first image is of a 40 year old triathlete. The second is of a 74 year old sedentary person. And the third is of a 70 year old triathlete. The differences are obvious. Use it or lose it. Muscle to flab.
This proves that being older need not mean having no muscle tone. The difference between the two triathletes and the sedentary 74 year old are striking. It is clear that even an older person who exercises can maintain good muscle tone. And although this is of a triathlete, just good regular activity that combines both aerobic and weight bearing exercise will maintain those muscles up to the very last breath. And it means better health, long life, and much less chance that a fall will lead to a broken bone.
Use it or lose it. Here is the proof.
Praise for Dr Schimpff
The craft of science writing requires skills that are arguably the most underestimated and misunderstood in the media world. Dumbing down all too often gets mistaken for clarity. Showmanship frequently masks a poor presentation of scientific issues. Factoids are paraded in lieu of ideas. Answers are marketed at the expense of searching questions. By contrast, Steve Schimpff provides a fine combination of enlightenment and reading satisfaction. As a medical scientist he brings his readers encyclopedic knowledge of his subject. As a teacher and as a medical ambassador to other disciplines he's learned how to explain medical breakthroughs without unnecessary jargon. As an advisor to policymakers he's acquired the knack of cutting directly to the practical effects, showing how advances in medical science affect the big lifestyle and economic questions that concern us all. But Schimpff's greatest strength as a writer is that he's a physician through and through, caring above all for the person. His engaging conversational style, insights and fascinating treasury of cutting-edge information leave both lay readers and medical professionals turning his pages. In his hands the impact of new medical technologies and discoveries becomes an engrossing story about what lies ahead for us in the 21st century: as healthy people, as patients of all ages, as children, as parents, as taxpayers, as both consumers and providers of health services. There can be few greater stories than the adventure of what awaits our minds, bodies, budgets, lifespans and societies as new technologies change our world. Schimpff tells it with passion, vision, sweep, intelligence and an urgency that none of us can ignore.
-- N.J. Slabbert, science writer, co-author of Innovation, The Key to Prosperity: Technology & America's Role in the 21st Century Global Economy (with Aris Melissaratos, director of technology enterprise at the John Hopkins University).