Circadian rhythm

Articles under this tag cover how your internal body clock affects sleep quality, testosterone production, recovery, appetite, and daily energy. Learn practical ways to align light exposure, meal timing, training, and supplements to support performance, mood, and long-term health.

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The essentials for circadian rhythm — then explore the latest posts below.

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

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

Dr. Susan Carter, MD avatar
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 ...

Patrick sleep and heat exposure: The science-backed way to fall asleep faster and sleep deeper

Patrick sleep and heat exposure: The science-backed way to fall asleep faster and sleep deeper

Dr. Susan Carter, MD avatar
Dr. Susan Carter, MD: Endocrinologist & Longevity Expert
Dec 28, 2025 · 10 min read

A warm bath, shower, or sauna taken about 1–2 hours before bedtime can help you fall asleep faster and sleep more efficiently by increasing skin blood flow and speeding the post-heat drop in core body temperature. Keep the bedroom cool and use this “heat-then-cool” timing to nudge deeper, more restorative slow-wave sleep for better recovery ...

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