Can exercise really improve your hormone levels as you get older?

Exercise does genuinely raise blood levels of a range of anabolic hormones in people over 40: testosterone, growth hormone, IGF-1 (a growth factor), SHBG and DHEA all rise in measurable ways. This holds for both men and women, and whether you do strength training, endurance training or interval training makes little difference in that regard. The effects do vary widely: some studies see a small difference, others a very large one, depending on the population and the protocol.

The picture is less clear when it comes to cortisol (the stress hormone) and insulin. Studies contradict one another on those, and there is as yet no clear-cut answer on how training affects those hormones in older adults. It is fair to say here: we do not yet know well enough.

The practical significance is strongest when it comes to muscle preservation. As we age, testosterone and growth hormone decline, and that contributes to muscle loss (also known as sarcopenia). But inactivity, poor nutrition and inflammation also play a role. Targeted strength training lasting more than ten weeks yields on average around 3 kg of additional muscle mass and roughly 25% greater strength. That is solidly established and is probably the most concrete health benefit of exercise for older adults.

One additional point worth knowing: newer weight-loss medications such as semaglutide cause not only fat loss but also a considerable amount of muscle loss, comparable to more than ten years of ageing. Strength training can reduce that risk. If you are using such a medication, combining it with exercise is therefore especially important.

Creatine as a supplement to strength training appears to offer benefits for muscle and bone in postmenopausal women, but the evidence for this is thinner than in men. In addition, two authors of the key study on this topic are advisors to a creatine manufacturer, which means those results should be viewed with a degree of caution.