A new study has found that 12 weeks of exercise training improved artery health and function in middle-aged and older men with low-to-normal testosterone levels, whereas testosterone therapy provided no benefits, according to a press release.
Men’s natural aging process includes decreased testosterone and physical activity levels, which often lead to declines in artery health and function. To combat the symptoms of decreasing testosterone levels, which can include low energy, reduced muscle mass, and reduced vigor, men are often prescribed testosterone replacement therapy. In the absence of any new clinical indications, testosterone sales have increased 12-fold globally in the past several decades.
“This global increase in testosterone use has been very large, particularly among middle-age and older men who might see it as a restorative hormone to increase energy and vitality,” said study author Daniel J. Green, PhD, a cardiovascular exercise physiology researcher in the School of Human Sciences at the University of Western Australia, in a press release. “However, previous studies are mixed as to whether replacement testosterone is beneficial or not, or whether it provides additional benefit over and above the effects of an exercise program.”
The team evaluated men aged 50 to 70 years with no history of cardiovascular disease, higher than normal waist circumferences, and testosterone levels that were in the low to normal range. They excluded current smokers, men currently on testosterone treatment, and men on medications that would alter testosterone concentrations.
At the beginning and end of the study researchers measured artery function using a method that increases blood flow inside an artery. This assesses whether the inner lining of the artery is healthy and can help the artery to dilate.
There were 78 participants randomized into 4 groups: 21 men received topical testosterone and completed a supervised exercise program; 18 men received testosterone with no exercise; 20 men received a placebo and no exercise; and 19 men received a placebo with exercise. The fitness regimen included aerobic and strength exercises 2 to 3 times a week and was supervised in a research gymnasium.
The investigators found that testosterone treatment increased the levels of the hormone to above average levels in 62% of men in the groups receiving the treatment. Exercise training also increased testosterone levels, although the levels were highest among the men who also received testosterone treatment.
Artery function and health improved in the groups who received exercise training, but no improvement was found in those who received testosterone without exercise training. Artery function in response to testing improved by 28% in the group who received exercise without testosterone, and by 19% in the group who received a combination of testosterone and exercise. Notably, the researchers did not see changes in other tests that stimulated muscle cells in the middle of the artery wall, following exercise training, testosterone treatment, or the combination of the 2.
“The results of our study suggest that if you are a healthy but relatively inactive middle-aged or older man with increased abdominal girth, and you are worried about your risk of heart attack, stroke, or diabetes, then an exercise program with some support and supervision can help to improve the function and health of your arteries,” Green said in the press release. “Testosterone therapy may have some benefits, for example in increasing muscle mass in the legs, however, we didn’t find any benefits in terms of artery function, which is a determinant of the future cardiovascular risk.”