Cycle-syncing: not supported
A 2024 study and reviews from 2020 and 2023 found that menstrual-cycle phase did not meaningfully affect muscle protein synthesis or resistance-training adaptation, with at most a trivial effect on performance. Train consistently and adjust by feel. The full breakdown of what the cycle does and does not change →
- PubMed 39630025 (2024). View study ↗
What does change: energy and temperature
In the luteal phase — the second half of the cycle — resting energy expenditure rises slightly, on the order of +6.9% sleeping energy expenditure, alongside about +0.27°C core temperature, and appetite tends to rise with it. That is a real, measured change. It is a reason to expect more hunger, not a reason to train differently.
- PubMed 7985630 (1994). View study ↗
Hydration: a correction
Despite widely repeated claims, menstrual-cycle phase does not meaningfully change overall fluid balance or plasma volume. The luteal phase does run slightly warmer. Hydrate to thirst, a little more in the heat — there is no phase-specific hydration protocol to follow.
- PubMed 31641955 (2019). View study ↗
Sleep across the cycle
Sleep often gets lighter premenstrually. Luteal-phase rises in core temperature and changes in REM are part of why — and it is the same thermoregulatory reason that a cool room and a warm bath before bed help generally.
- PubMed 35659080 (2022). View study ↗
Perimenopause and postmenopause are not the same
This distinction is routinely collapsed and it should not be. A 2025 review found that during perimenopause, strength training, endurance work and Tai Chi did not improve bone density or lean mass — whereas in early postmenopause, strength training did. Why the stage changes the result →
- PubMed 40967555 (2025). View study ↗
PMS supplements: what has RCT support
A 2025 review of 31 randomised controlled trials found the most consistent benefit for premenstrual psychological symptoms from vitamin B6, calcium (about 1000 mg/day or more), and zinc. Food first where you can. On the B6 dose, read the caution below before acting on it.
- PubMed 38684926 (2025). View study ↗
Menopause symptoms and hormone therapy
Hormone therapy is the most effective treatment for hot flashes — roughly a 75% reduction versus placebo — and improves sleep specifically in women who have vasomotor symptoms. This is a medical decision that belongs with a clinician; it is included here for information, not as a recommendation.
- PubMed 15495039 (2004). View study ↗
Sprint training after 30
Sprint performance declines faster in women after 30 than VO₂ max does, which is the argument for treating sprint interval work as a priority rather than an optional extra.