We often think about our muscles' straining and our breathing when exercising. But what we don't usually consider is how our bodies' underlying mechanisms assist us. While we can't see it, our bodies support us by firing innumerable chemical reactions, including hormones. Even though they aren't as visible as muscles, one's ability to exercise can be significantly impacted when these hormones are affected. This is especially true for women, who often undergo hormone fluctuations as a part of their bodies' natural functions.