By observing our fellow humans, we probably realize that the biological age of our
bodies does not always correspond closely to our chronological age. One measurement
of biological age is average leukocyte (white cell) telomere length. Telomeres
are protective buffers at the ends of chromosomes. Young people’s cells generally
have longer telomeres than those of older people because, over time, with each cell
division, the telomere ends become shorter.

A study compared changes in telomere length in middle-aged men and women
who did not exercise with those started on a supervised program of either aerobic
exercise (brisk walking, jogging, or high-intensity training) or resistance training
with weights. The aerobic trainers lengthened their telomeres, whereas the weight
trainers did not, even though they too gained aerobic fitness compared to when they
were inactive. This suggests that different forms of physical activity may provide
different benefits.

Evidence that exercise can keep our body’s cells biologically younger comes from a
study of individuals who persisted with high levels of physical activity for as many
as 50 years.18 The athletes in their 70s were found to be biologically about 30 years
younger than their chronological age as judged by both the study of capillaries and
enzymes in their tissue samples, and by their aerobic capacity—a key health marker
for all-cause mortality. Their aerobic capacities were about 40% higher than that of
inactive people the same age. Gretchen Reynolds, writing on physical activity and
health in the New York Times, noted that there is evidence that a decade after fitness
training, health benefits persist, even among those who stop exercise, as measured
by blood pressure and insulin sensitivity, but not with regard to maintaining aerobic

Nielsen television survey data indicates that U.S. adults watch an average of more
than five hours of TV a day. A study of young adults in China found that independent
of physical activity and energy intake, each one-hour increase in average
daily television watching was associated with a modest decrease in mean telomere
length, signifying approximately a 1.2 to 1.8 years increase in biological age. The
difference in telomere length for a three-hour a day increase in television watching
would be roughly comparable to the difference in telomere lengths between smokers
and non- smokers.

There is substantial variation between U.S. states in the proportion of Americans
who are physically inactive. Of course, there are many variables that could affect
health and longevity, but the average life expectancy in the four states (Colorado,
Oregon, Utah, Washington) with 15% to less than 20% of adults inactive was about
age 80. This can be compared to a life expectancy of age 75 to 76 in the seven
states (Alabama, Arkansas, Kentucky, Louisiana, Mississippi, Oklahoma, Tennessee)
where 30% or more of adults were inactive.

This blog presents opinions and ideas and is intended to provide helpful general information. I am not engaged in rendering advice or services to the individual reader. The ideas, procedures and suggestions in that are presented are not in any way a substitute for the advice and care of the reader’s own physician or other medical professional based on the reader’s own individual conditions, symptoms or concerns. If the reader needs personal medical, health, dietary, exercise or other assistance or advice the reader should consult a physician and/or other qualified health professionals. The author specifically disclaims all responsibility for any injury, damage or loss that the reader may incur as a direct or indirect consequence of following any directions or suggestions given in this blog or participating in any programs described in this blog or in the book, The Building Blocks of Health––How to Optimize Your Health with a Lifestyle Checklist (available in print or downloaded at Amazon, Apple, Barnes and Noble and elsewhere). Copyright 2021 by J. Joseph Speidel.