R Lang & Associates
HOME ABOUT SPACE & AVIATION MEDICAL SCIENCE
Physiological Age of a Person
If you think there is an obvious insinuation about the “health drive” in today’s society involving regular exercise and well-living practices – there could be. People who have acquired the insight of these practices tend to stay healthier and live longer, and according to an acknowledged health and fitness expert:
“.. a 55-year-old may have the health and performance capability
of the average 25- to 30-year-old.”
Because of this variation, it was necessary to define a physiological age apart from the chronological age. Some have even substituted the term biological age for physiological age.
Since performance in the employment field is dependent on physical health factors, the serious issue of employment hiring involving physical activity is based on physiological age.
Likewise, an athlete who has been medically verified regarding their progress in the sport field will find it preferable to represent themselves with an “age-equivalent” (and not their birth-date). Some regard this as not unusual because of the obvious implications of the athlete’s efforts to achieve a higher health status.
Physiological factors that contribute to “sustained youthfulness” are body composition, cardiovascular function, and muscles and nerves.
Lean body mass is needed for physical performance and consists of muscle, skin, bone, and the internal organs. It has been found that regular physical exercise can increase the muscle mass regardless of age. Case studies have shown that the percent body fat of a trained 70-year-old can match that of a 19- to 25-year-old, and even maintain the same lean body mass. Loss of muscle mass is called sarcopenia and results from loss of muscle fibers and fiber atrophy, due to lack of use. People who use their strength regularly can retain their muscle function.
Aerobic exercise is deemed to yield the greatest overall benefit, and can be verified by the
Vo2max test when comparing trained versus untrained athletes.
.. when you exercise aerobically, your lungs actually increase in
size, capacity, and efficiency. Your heart becomes more powerful,
more fit with exercise, just like any other muscle. Your blood vessels
actually increase in number, and they may even become more flexible,
thereby forestalling any tendency toward arteriosclerosis. Some studies
also indicate that aerobic exercise reduces the cholesterol levels in the
blood overall, and that it may alter the cholesterol that is found in the
blood to a less dangerous type. Other aerobic benefits include lower
blood pressure, improved digestion, a clearer complexion, and generally
increased alertness .. 2
Another energy system that is studied is called anaerobic capacity, the ability to provide energy to the muscles without the use of oxygen using the process of glycolysis. The anaerobic system can be maintained through lifelong training, and in a study swimmers aged 46 to 56+ did not differ from 25- to 35-year-old swimmers in their ability to produce and remove lactic acid. Maintenance of muscle mass, especially fast-twitch fiber, maintain the anaerobic system and can be achieved by training at higher intensities.
Other factors of physiological age include family history, health habits, measure of blood pressure and cholesterol; and measures of strength, reaction time, vision, and hearing. It has been well documented that slowing the aging process comes from the physiological benefits of regular exercise, and that they are fairly certain that persons who are more physically active live longer than those who are inactive.
1. Sharkey, Brian J. (and Gaskill, Steven E.) Fitness & Health, 6th Ed., University of Montana/Human
2. Katz, Jane (with Bruning, Nancy P.) Swimming for Total Fitness, 2 ed., Doubleday, 1993.