deficiencies, including a reduction in testosterone levels, are often
acknowledged as a natural aspect of aging among males; however, the vast array
of treatments being offered to avoid decreased function indicates that men have
significant interest in maintaining youthful vigor.

What works? While testosterone
replacement is thought to be a viable option for treating clinical androgen
deficiencies in younger men, it is considered controversial—and probably not
helpful—for treating age-related hormone deficiencies in older men. On the
other hand, says a study published in the February issue of
& Science in Sports & Exercise
(2008; 40 [2], 223-33),
males may be able to dodge some of the age-related loss of sexual function just
by increasing their weekly cardio. Their muscle mass and strength could also

Authors recruited 102 previously
sedentary men aged 40-75 who were randomly assigned to a no-exercise control
group (controls) and an exercise group (exercisers). The exercisers met three
times per week for 12 months and were monitored by a fitness professional. They
participated in a warm-up and an exercise phase (treadmills, elliptical
machines, rowers and stationary bikes), as well as a cool-down phase.
Exercisers were educated on target heart rate and safe progression, and were
instructed to perform moderate- to vigorous-intensity exercise three times more
per week at home. No diet recommendations were made for either group.

At the end of the study,
the researchers found promising improvements in dihydrotestosterone (DHT) and
sex hormone-binding globulin, as well as greater cardiopulmonary fitness, in
the exercise group versus the controls. There were no significant changes to
the other androgens tested—testosterone, free testosterone and estradiol. The
study authors conceded that more research was necessary and recommended that
future studies include resistance training, since this exercise methodology is
known to increase testosterone levels, at least temporarily. The authors stated
that “given the controversy surrounding exogenous androgen supplementation,
modest enhancements of DHT levels in middle-aged and elderly obese men through
exercise may offer a lower-risk approach for improved health.” This finding
also gives older male exercisers yet another motivation for returning to the gym
on a regular basis.