Progress in our society has been measured in large part by events like the Industrial Revolution and the Information Age.  As a result, more of us are working with our brains instead of our bodies.  But that may not be such a good thing after all.  In our current global economy, we are dealing with more competition, unprecedented levels of stress and diminished physical activity.  America has become a nation of spectators.   Far too few are getting the exercise that lowers blood pressure, burns away body fat, strengthens muscle and bones, lowers cholesterol, improves mood and sleep, and protects against diabetes, dementia, several cancers, heart attacks and strokes.  But what exactly is the right kind of exercise?

Although numerous studies have demonstrated substantial health benefits from physical exercise, there is debate about the optimal type, duration and intensity to achieve the most favorable result.  When you mention exercise to most people, it congers up images of tedious endurance training; that is, traditional “cardio” that many exercise gurus tell you to do.  But recent scientific studies are pointing to another, more efficient option to strengthen your heart, improve lung function and overall fitness.  Shorter bursts of vigorous exercise benefits heart health as much as tedious endurance training.

A small study done at McMaster University in Canada compared healthy men and women riding stationary bikes.  Some exercised five days per week doing 40-60 minutes of moderate-intensity cycling.  Others did four to six sets of 30-second sprints on the bike allowing 4-5 minutes of recovery between sets; with a total exercise time of 15-25 minutes just three days a week.  After six weeks, the researchers found that the intense sprint interval training improved the structure and function of arteries as much as traditional, longer endurance exercise.

A larger study, following 13,000 people for 15 years in the Harvard Health study found that people live longer if they do vigorous exercise, but not if they only do light or moderate exercise.[1]   Another study looking at the cardiovascular benefits of exercise in people following coronary artery bypass surgery (CABG) found that higher intensity interval training improved aerobic capacity (VO2) significantly better than moderate intensity continuous training.  In fact, the study data showed that the 4 week improvement in VO2 in the interval training group was greater than that achieved in the moderate continuous training group after 6 months.[2]

What is VO2?  There are a number of parameters that can be measured to assess your overall cardiovascular health but the one of the best is your aerobic capacity, otherwise known as your VO2 max.  Measuring VO2 max reveals how well your lungs can get oxygen into your blood, how efficiently your heart can pump that blood to your organs and exercising muscles and how well those muscles can utilize the oxygen for energy production.  The more oxygen your body can use, the better your body works.

Mitochondria are the power plants where fuel is burned, energy is produced and harmful free radicals are neutralized.  The number of mitochondria that you have in your cells determines your performance capacity.  But that number is not fixed.  There are several complex pathways that lead to an increased number of mitochondria.  The best known and most effective way to produce more mitochondria is with exercise.[3]   Mitochondrial production increases in direct proportion to the amount of physical activity performed.[4] [5]

I have previously reviewed in detail three nutritional supplements, Resveratrol, Alpha Lipoic Acid and L-arginine, which have been shown to augment mitochondrial production and thereby improve oxygen consumption.  Quercetin, a compound found in berries, onions grapes and red wine can also improve VO2.  A study using elite cyclists demonstrated a 4% increase in VO2 over a six week trial [6], and a similar increase in healthy but untrained individuals given quercetin supplements over seven days.

Clearly, people that stay physically active throughout life reap substantial benefits from exercise.  But what about those getting a late start?  Can beginning an exercise program at any age make up for years of sedentary living?  The short answer is a resounding “yes”.

A study spanning 35 years in Sweden strongly suggests that starting to exercise at or after 50 years old is better than never starting at all.  Another British study traced men over 18 years, at an average age of 63.  This study revealed a strong link between exercise and survival.  A third study from Norway found that men who were physically fit enjoyed substantial protection from cardiovascular disease and early death.   Not to be outdone, a study of American veterans followed men over 25 years and noted a 38% lower mortality in men who were physically fit.  Just as important was the finding that men who were unfit at the start and improved their fitness had a 35% lower mortality than those who remained unfit.

So, improving your fitness level strengthens your heart, improves your vascular system, enhances lung function, reduces your risk for a myriad of chronic diseases and ultimately protects against premature death.  But exercise alone is not sufficient.  It should be part of an overall adoption of healthy lifestyle habits:  eating more fruits and vegetables, avoiding processed foods and added sweeteners, not carrying around excess body fat, not smoking, getting more sleep and managing stress.  If you are over 50 you should have a thorough medical evaluation prior to beginning an exercise program and seek guidance from an experienced trainer or exercise physiologist.  At Alternity Healthcare, we perform an extensive evaluation including VO2 testing on all of our new patients.

 It is never too late or too early to start exercising.  You will feel better, look better and live better.  You could then spread the word to your children and younger friends who have become distressingly inactive, overweight and lazy.  Remember, leading by example is most effective.

[1] Lee I-Min, Paffenbarger R.  Associations of light, moderate and vigorous intensity physical activity with longevity.  Amer J Epidemiol 2000; 151(3)

[2]Moholdt T, et al.  CABG Patients get More Long-term Benefit from Aerobic Interval Training. Am Heart J 2009;158:1031-1037

[3] Reznick RM, Shulman G. The role of AMP-activated protein kinase in mitochondrial biogenesis. J Physiol 2006; 574:33-39

[4] Baar K, Wende AR, Jones T, et al. Adaptations os skeletal muscle to exercise: rapid increase in transcriptional coactivator PGC-1. FASEB J 2002; 16:1879-86

[5] Coffey VG, Hawley JA. The molecular basis of training adaptation. Sports Med 2007; 37:737-763

[6] Holden S, MacRae M et al. Dieary antioxidnt supplementation combined with quercetin improves cycling time trial performance. Intl J Sport Nutrn and EX Met 2006; 16: 405-419