Exercise can Reverse That
For busy leaders who think they don’t have time.
You already know you should exercise. You don’t need another lecture about cardiovascular health or weight management. What you may not know is what’s happening inside your skull while you skip the gym.
A randomized clinical trial published this year in the Journal of Sport and Health Science found something that should matter to anyone who leads anything: after twelve months of regular aerobic exercise, participants showed measurable reversal in brain aging. Their brains looked younger on advanced scans than a control group that didn’t change their activity. The researchers called it rewinding the brain’s clock. This is one of the first studies to show that a year of aerobic exercise may actually reverse brain aging in early and midlife adults.
A separate study published in July confirmed that strength training adds its own dimension — just two resistance training workouts per week improved memory and helped preserve key brain regions linked to cognitive function.
The mechanism is still being mapped, but the finding is not in dispute: the brain responds to physical stress by becoming more resilient. The brain that exercises regularly is functionally younger than its chronological age. The brain that doesn’t — isn’t.
For the Men in the Room
The brain benefits of exercise don’t arrive in isolation. They come packaged with something that matters to male leaders in particular: testosterone.
Physical exercise acutely increases testosterone levels in men, with resistance training showing a greater and more sustained increase than aerobic exercise alone. The acute spike is measurable immediately after a session and persists longer following resistance training than cardio. Concurrent training — combining endurance and resistance work — produced the strongest sustained results: concurrent training significantly increased serum testosterone levels compared to untrained controls, and also improved sexual function scores in men over fifty.
Testosterone isn’t just a performance metric. It’s the hormonal substrate of the decisiveness, competitive drive, and stress resilience that leadership demands. The executive whose testosterone has been declining for a decade — as it does at approximately one percent per year after thirty — is making decisions with a different neurochemistry than the executive who trains consistently.
The gym is not vanity. It is maintenance of the instrument you use to lead.
The Mood Question
The largest synthesis of exercise and mental health research published this year leaves little room for debate. A meta-analysis in the British Journal of Sports Medicine compiled 63 studies involving nearly 80,000 participants. Exercise reduced depression symptoms with a standardized mean difference of -0.61 and anxiety symptoms with -0.47, with aerobic exercise showing the most substantial impact across both.
A 2018 Lancet Psychiatry study of 1.2 million Americans found that people who exercised reported 43% fewer days of poor mental health per month than otherwise similar people who didn’t. It’s an observational association rather than proof of cause and effect, but the sweet spot was clear: about 45 minutes, three to five times a week. More wasn’t better.
In a small randomized trial of previously inactive working adults, four weeks of exercise reduced stress and emotional exhaustion and improved well-being, with large effects. Cardio did more to relieve the strain, while weight training did more to build a sense of accomplishment, so the best answer for a busy leader is both.
The brain is younger. The testosterone is higher. The depression and anxiety markers are lower.
The prescription has no side effects, no co-pay, and no waiting list.
The only barrier is scheduling it.
Claude AI helped with this article.
Sources:
Crisafio et al., Journal of Sport and Health Science, 2026.
GeroScience, “Physical Activity to Counter Age-Related Cognitive Decline“, 2025.
Mavros et al., “Mediation of Cognitive Function Improvements by Strength Gains After Resistance Training in Older Adults…” (The SMART trial), Journal of the American Geriatrics Society, 2017.
Tu et al., “Effect of acute exercise on the dynamics of testosterone levels“, PeerJ, January 2026.
Parastesh et al, “The effect of concurrent endurance-resistance training on serum testosterone levels… in older men,” Termedia Publishing, 2025.
Munro et al., “Effect of exercise on depression and anxiety symptoms“, British Journal of Sports Medicine, February 2026.
Chekroud SR, et al. “Association between physical exercise and mental health in 1.2 million individuals in the USA between 2011 and 2015: a cross-sectional study.” Lancet Psychiatry 2018;5(9):739-746.
Bretland RJ, Thorsteinsson EB. Reducing workplace burnout: the relative benefits of cardiovascular and resistance exercise. PeerJ 2015;3:e891. doi:10.7717/peerj.891 (PMID 25870778).
