Cortisol

Cortisol is the body’s primary stress hormone, influencing energy, sleep, recovery, and body composition. This topic covers how cortisol affects testosterone, training performance, and long-term health—and practical ways to manage stress for better results.

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The essentials for cortisol — then explore the latest posts below.

Seasonal affective disorder or hormones? A men’s guide to winter mood, testosterone, and sleep

Dr. Susan Carter, MD: Endocrinologist & Longevity Expert

Dec 29, 2025 · 12 min read

In men, winter “low mood” can be true seasonal affective disorder (a recurrent depressive pattern that starts in late fall, peaks in winter, and eases as daylight returns) or a look‑alike driven by physiology—less morning light can delay your circadian rhythm and prolong melatonin, while testosterone, cortisol, and thyroid shifts can produce the same fatigue ...

Can somatic exercises for weight loss actually help men get lean?

Dr. Jonathan Pierce, PhD: Clinical Psychologist & Neuroscience Specialist

Dec 27, 2025 · 9 min read

Somatic exercises don’t meaningfully drive fat loss through calorie burn, but they can help men get leaner by shifting the autonomic nervous system from sympathetic “fight-or-flight” to parasympathetic “rest-and-digest,” lowering chronic HPA-axis stress and cortisol — a hormone linked to visceral abdominal fat accumulation in men. If you’re training hard and dieting but your midsection ...