weights4If you need to do a task that requires as much physical strength, endurance and steadiness as you can muster–such as moving heavy furniture or building a shed–and you can plan it around your cycle, you may want to schedule it during your Week 1 (menstrual week), Week 2 (the week leading up to and including ovulation) or Week 4 (your premenstrual week).

But, you may want to skip your Week 3 (the week right after ovulation).

According to a new small study, on these days, steadiness declines and your muscle power weakens 23% compared to its peak at ovulation. Researchers chalk it up to high progesterone, which blunts your physical force.

Can’t avoid doing a strenuous task during your Week 3? Then, try to schedule it for the afternoon. A small 2002 study shows you have 8% more power in the later part of the day than the early morning during your Week 3 due to a slightly higher body temperature.