There's a reason some training sessions feel effortless and others feel like you're moving through concrete. Your cycle plays a direct role in how strong you are, how quickly your body recovers, and even how coordinated your movement feels day to day.
And once you understand the pattern, you can stop fighting it — and start using it.
It starts with oestrogen and progesterone
The two hormones that most directly influence physical performance are oestrogen and progesterone.
Oestrogen supports muscle protein synthesis, has an anti-inflammatory effect, and is associated with higher pain tolerance — all of which make the first half of your cycle a naturally stronger window for training.
Progesterone, which dominates the second half, has a catabolic effect on muscle tissue, raises your core body temperature, and can increase perceived effort during exercise. In other words, the same workout can genuinely feel harder in your luteal phase — and that's physiology, not a lack of motivation.
What changes at each phase
MENSTRUAL · DAYS 1–5
Hormones at their lowest. Some research suggests pain tolerance may dip. Prioritise gentle movement, mobility work, and warmth. Riley's organic cotton range is designed for comfort exactly here — free from irritants when your body is most sensitive.
FOLLICULAR · DAYS 6–13
Oestrogen rising. Strength, speed and coordination all improve. Muscle repair is faster. This is the phase to push harder, try new movements, and set personal bests. Your body is primed for it.
OVULATORY · DAYS 14–20
Peak oestrogen and testosterone. Maximum strength and confidence. This is your power window — ideal for heavy lifting, HIIT, competitive sport and high-intensity output. Note: ligament laxity increases slightly around ovulation, so warm up well.
LUTEAL · DAYS 21–28
Progesterone rises, core temp increases, perceived effort goes up. Strength output may reduce by 5–10%. Recovery takes longer. Prioritise sleep, lower-intensity sessions, and don't judge performance against your follicular-phase highs.
Coordination and injury risk
This is the part that surprises most people. Research into female athletes has found that coordination, balance, and neuromuscular control shift meaningfully across the cycle.
Around ovulation, relaxin — a hormone that increases joint flexibility — peaks alongside oestrogen. For most movement, this feels like fluidity and freedom. But for high-impact sports or heavy compound lifts, it also means slightly higher injury risk, particularly to the ACL. Being aware of this doesn't mean avoiding exercise — it means warming up properly and not skipping mobility work in that window.
Recovery is not the same every week
Muscle repair is genuinely faster in the follicular phase, when oestrogen's anti-inflammatory properties are working in your favour. In the luteal phase, that advantage reduces — your body needs more time, more sleep, and more nutrition to recover from the same training load.
Working with that, rather than pushing the same intensity regardless, is how you avoid accumulating fatigue and burning out across a season.
Your cycle isn't a limitation on your performance. It's a map. And the athletes and active women who understand it — adjusting load, intensity and recovery accordingly — are the ones who train consistently, recover well, and feel better for longer.
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