Estrogen and its effects on muscles and joints.

Achy Knees? When talking about athletic or activity-related injuries in females, you might be surprised to hear that knee injuries occur more in females than males! Previously, knee injuries have been attributed to differences in female anatomy, general muscle strength, higher flexibility, and even in movement patterns. So, you might be asking... “Does this have something to do with my period?” Well, let us tell you!

During our cycle, estrogen and progesterone go through fluctuations, causing a lot of changes to our bodies. The change we’re going to dive into today involves a functional property of our muscle tissue... muscle stiffness. We may think, “muscle stiffness is bad,”— like when you wake up in the morning with a stiff back or neck and you’re right, but there’s more to the story. A certain amount of muscle stiffness actually helps keep our joints stable during activities and helps us to respond efficiently to fast movements!

According to a recent research study, when estrogen levels are at their peak during Phase Two, this “stiffness” property in our muscles decreases. What does this mean for you? If you are exercising or doing any sort of activity, your muscles may be generally not as able to respond as quickly to that exercise during this Phase. Since our joints may not be as protected by our muscles during Phase Two, you may want to increase awareness around the kinds of movements you do.

Now what? No need to be worried if you want to get in a killer workout during Phase Two (since you might be feeling great!). A proper warm-up prior to exercise is said to help reduce the effect estrogen has on the muscle tissue. Next time you go to exercise, you can think about being mindful of extreme movements, focus on proper form, and take the time to recover to help avoid injury. You got this!

Science, Feminism and Love.

Eiling E, Bryant AL, Petersen W, Murphy A, Hohmann E. Effects of menstrual-cycle hormone fluctuations on musculotendinous stiffness and knee joint laxity. Knee Surg Sports Traumatol Arthrosc. 2007;15(2):126-132.