The surprising truth about your menstrual cycle and exercise
It may be easy to blame slumps in training on your menstrual cycle, whether it be lifting less, having worse DOMS, or feeling out of breath sooner on your runs. Previous research has suggested that working out at different points in your period makes a difference, finding that women gained more muscle by doing more of their strength training in a particular (follicular) phase. However, a new study says that working out at all stages of your cycle results in similar levels of fitness improvements.
The study
A group of 12 women participated in two six-day study periods.
They exercised one of their quads with two workouts each during the two phases of the menstrual cycle: the luteal phase (the latter half, which begins after ovulation. lasts until the start of the next period, and sees progesterone peak), and the follicular phase (the first stage, when the egg matures in the ovaries, and oestrogen peaks).
Completing three sets of leg extensions to failure, they performed this unilateral (one-sided) resistance exercise, workout out the opposite leg in a counterbalanced way.
The results
Cycle tracking, blood sample and urinary test kits were used to track the effect of the menstruation period on muscle building, also called muscle protein synthesis (MPS), and myofibrillar protein synthesis, or adding amino acids to skeletal muscle protein. Myofibrils are rod-shaped organelles within muscles that control contractions.
There were no significant differences between the two phases in muscle building in the resting or exercised legs, suggesting it didn't matter which menstrual phase participants trained within to build muscle. Women's hormone levels weren't shown to affect a workout's efficacy drastically.
However, muscle protein synthesis was ever so slightly higher in the resting and exercised legs during the follicular phase, though not to a statistically significant level.
What does this mean for us?
The thinking behind the follicular phase being more beneficial for muscle building stems from the elevated oestrogen levels promoting muscle synthesis and hypertrophy, or increase in muscle size.
This isn't the first study to suggest that the menstrual cycle has no effect on the impact of resistance training. Given the inconclusive evidence, it's best to track for yourself and see how you feel during different cycles of your period. If there is a specific window when you seem to perform better, then perhaps menstrual periodisation for you. If not, aim for a consistent level of intensity throughout the month.
If you're considering menstrual periodisation, consult a fitness professional for a tailored programme.
Read next:
Cut through the noise and get practical, expert advice, home workouts, easy nutrition and more direct to your inbox. Sign up to the WOMEN'S HEALTH NEWSLETTER
You Might Also Like
