Birth Control Pills Affect Muscle Gain

Back in the day when I was on birth control pills, I remember a period of time when I went through various brands/types to see which one negatively affected my hormones the least. The first batch made me gain weight quickly, while the second batch made me feel irritable not just the three to five days a month I was accustomed to, but all month long. It got so bad, if my husband just looked at me funny, I would proclaim, “Just divorce me then! You obviously don’t love me!” Eventually I found one that did its job without turning me into Captain Insane-o. The goal for women on birth control pills is, essentially, to do just that: work its magic without affecting the body (or mind) too much. So, active women, beware! A recent study has shown that women who regularly use oral contraceptives often report lower levels of hormones and impairment in gaining muscles.

Researchers in the study include Chang-Woock Lee and Steven E. Riechman (Texas A&M University, College Station) and Mark A. Newman (University of Pittsburgh). The findings from this study were presented this year at the 122nd Annual Meeting of the American Physiological Society. There were close to 75 female participants in the study and their ages spanned from 18 to 31. These participants were split into two groups and the trial consisted of RET or resistance exercise training for ten weeks. The first group had 34 females who took birth control pills. The second group had 39 females who were not on birth control pills. Each day, the women were asked to take 0.5 grams of protein for each pound they weighed (for example, a 130 lb woman would consume 65 grams of protein a day). Taking this protein ensured that the women used enough protein and calories in order for muscle growth to be stimulated.

Each participant made sure to exercise, under supervision, three times each week. Their exercise routine included leg extensions, arm curls, chest presses and abdominal crunches, to name a few. The women in the study did three sets of each exercise with six to ten repetitions each. Researchers performed blood work on the participants both before and after the ten week study span. This was done to measure catabolic and anabolic hormone levels. The data concluded that there were a vast difference in terms of lean mass gain between those females who took birth control pills and those who did not. Researchers noted, “We were surprised at the magnitude of differences in muscle gains between the two groups, with the non-OC women gaining more than 60% greater muscle mass than their OC counterpart.” While they understand that the study has shown that use of oral contraceptives diminishes muscle gains, they are quick to add that “future studies are needed to help explain the reasons behind the results.”