Very little evidence for training based on menstrual-cycle phase
Researchers from McMaster University in Canada and Manchester metropolitan University in the UK joined forces and evaluated all relevant meta-analyses and systematic reviews about the impact of menstrual-cycle phase on resistance exercise performance and training adaptations. Their main conclusion was that there is very little, weak and inconsistent evidence that would support menstrual-cycle training when it comes to strength, exercise performance, and muscle growth.
On top of this, there are studies comparing muscle growth resulting from resistance training between men and women and they show equivalent relative gains in muscle size and strength. These findings make it clear that there are big differences among individuals. But these studies also show that it’s unlikely that there are big differences within one person. Based on the overall current evidence, it would be too soon to say that it’s important to adapt training to the phase of the menstrual cycle.
Should you take menstrual cycle into consideration?
Even though the evidence currently doesn’t show that menstrual cycle has a significant effect on training adaptations and performance, it could still be one of the factors you or your coach consider. After all, you know how much menstrual symptoms influence your ability to train and perform on the bike. But you always have to compare this to other key factors that impact athletic training and performance, such as the following:
- Short- and long-term goals
- Amount of fatigue
- Sleep quality
- Stress levels
- Injury
- Motivation
- Training-related logistics
You may find that making adjustments in your training plan based on the phase of your menstrual cycle works for you. That’s great, so definitely keep doing that if that’s the case. But for the average person out there, making training prescriptions based on cyclical hormonal changes is not an evidence-based approach.