22/02/2026
Sunday mornings - watching my youngest climb at Awesome Walls.
Interesting comp prep flyer on the table.
So, periods. I'd agree that the evidence is conflicting, however there is research to suggest that athletic performance is impacted by the menstrual cycle.
Perceived changes can be with strength, speed and agility and often coincides with fatigue, pain and mood changes.
Objective changes can happen in energy metabolism (endurance can improve with higher oestrogen levels). Strength and output can be decreased with a change of muscle efficiency when progesterone levels increase.
In clinic we're often interested in injury risk and injury healing in particular when looking at return to sport and rehabilitation. It's very individual and an approach looking at other parameters such as age and training are also important.
For more information this study is useful:
https://pmc.ncbi.nlm.nih.gov/articles/PMC12225299/