The Fountain of Youth

Exercise regularly and you will maintain a stronger immune system, lower your risk of a heart attack, and have less chance of developing diabetes. And over time maintain a better memory and lower your odds of developing dementia.


But even with those positives, the aging process moves inexorably onward. It has been estimated that after our peak at age 30, we lose between 5 and 10% of our physical stamina every decade, and as the years pass, that is reflected in the fatigue we feel at the end of the day.


Loss of stamina is a combination of less muscle bulk (strength) combined with a decrease in the effectiveness of our cardiovascular system (aerobic capacity) in providing the oxygen our muscles need to function.


Regularly pushing the cardiovascular system (High Intensity Interval training - HIIT) and stressing the musculoskeletal system (weight or resistance training) can blunt the rate of decline. Just 30 minutes a day of either HIIT or working out at the gym can have a significant impact on your energy levels.


There is little question as to the mental lift you experience from taking charge of your health. But how much physiologic return do you get for that 30 minutes a day? And could you do better?


Investigators in Indiana (Ball State) located 28 men and women who had exercised regularly for 50 years. Most took up running in the health conscious 1970’s and then just stuck with it. They enjoyed it and made it part of their life. Most were recreational athletes (running, biking, swimming) and only a few actually exercised to be able to compete. On average, group members exercised 5 days (or 7 hours) a week.


Investigators also identified a healthy peer group (also average age of 70 years) who were not regular exercisers, and a 3rd group of active, but not athletic, 30 year olds. They then tested all subjects to determine their aerobic (cardiovascular) capacity as well as taking a small sample of leg muscle tissue (a minor procedure).


The findings were even more impressive than had been expected.


First, the analysis of number of capillaries (need to deliver oxygen to the muscle fibers) and concentration of muscle cell enzymes (needed to process oxygen and glucose to provide energy for physical activity) in the muscles of the athletic seniors were identical to those of the 30 year old comparison group.


Even more astounding was the finding that the aerobic capacity (the measure of how much work a subject could do per minute), although slightly less than that of the 30 year old comparison group, was 40% better than their sedentary peers.  And using information in the medical literature, equivalent to the aerobic capacity of active adults 30 years their junior.


This study shows how effective regular aerobic exercise can be as a tool to blunting the effects of aging.  Instead of the inexorable 5 to 10% decrease per decade described in many articles on aging and human physiology, this group of regular exercisers slowed the rate of decline significantly. If you believe the data, to perhaps 3 or 4% per decade.


It may not be as easy as drinking the water of the fountain of youth, and not all of us have the inclination or time to take on this level of exercise commitment, but  if you did, it would appear that for an average of an hour of aerobic exercise a day (17,500 hours over 50 years) you gain an additional 30 years of robust exercise capacity. Or about 1 day for each hour invested. In my book, that’s a pretty good ROI (return on Investment).


References:

https://www.nytimes.com/2018/11/21/well/move/regular-exercise-may-keep-your-body-30-years-younger.html


https://www.physiology.org/doi/abs/10.1152/japplphysiol.00174.2018