Women who practice birth control tend to enjoy the convenience and relative reliability of oral contraceptive pills, but there are risks and disadvantages associated with use of the pill. Along with your concerns about pill-related weight gain and whether the pill increases your risk of developing certain cancers, you might wonder if birth control pills hinder muscle development. There is some evidence that use of the pill can interfere with a female's muscle-building efforts, so if you take the pill and building muscle is a priority for you, speak to your doctor.
Athletes and Birth Control Pills
Women choose to take birth control pills for a variety of reasons, including to prevent pregnancy, control acne and regulate the menstrual cycle. Elite female athletes often resort to taking the pill to regulate their periods. High-performance athletes and other highly active women often experience a decrease in estrogen levels as a result of their training, which can result in menstrual irregularities or complete absence of the monthly period. Such changes in – or loss of – the monthly period can affect a woman’s bone strength, leaving her at higher risk for stress fractures. Because there is evidence suggesting that birth control pills offer protection from stress fractures, doctors often prescribe birth control pills for female athletes with the intention of getting their menstrual cycles back on track.
There are many benefits to building muscle, including improved body composition, better immune-system function, and faster metabolism, according to personal trainer Bill Sonnemaker. Female bodybuilders and other athletes who aim for top performance focus a great deal on building muscle mass, because they are so dependent on the strength that results from increased musculature. Assistant professor of health and kinesiology, Steven Riechman, points out that active women who devote considerable time and energy to building muscle are understandably concerned about how birth control pills might interfere with the achievement of personal training goals.
In 2009, researchers at Texas A&M University presented the results of a study to determine whether oral contraceptives impact negatively on a woman’s ability to build muscle. In the study, 73 women between the ages of 18 and 34 completed 10 weeks of resistance training. Approximately half of the women who participated were taking birth control pills at the time of the study. Researchers concluded that the group that was taking the pill developed 40 percent less muscle mass than the group that was not taking the pill. Exercise physiologist Chang Woock Lee, one of the researchers involved in the study, attributes the difference in muscle-building ability to oral contraceptive use.
Lee suggests that hormonal changes that occur as a result of taking the pill are responsible for limiting muscle-building ability. He points out that before and after the trial, women using oral contraception had dramatically lower blood levels of anabolic hormones -- which contribute to muscle development -- than did women who were not taking the pill. Compared to non-pill-users, women taking oral contraceptives also had substantially higher concentrations of cortisol, a hormone which contributes to the breakdown of muscle.
Researchers who presented the results of the Texas A&M study pointed out that that birth control pills containing medium- or highly androgenic progestins were more problematic for muscle building than pills containing low-androgenicity progestins. If you are frustrated with your inability to build muscle and suspect oral contraceptives are to blame, ask your doctor about switching brands. Keep in mind, there are other variables that can contribute to the success or failure of your muscle-building program. If you are discouraged by the results of your training efforts, discuss your regimen with your trainer. She'll likely consider what equipment you use, the frequency of your workouts, the type, number and order of exercises you perform, the number of sets and repetitions you complete, the amount of weight or resistance you work with and the amount of time you currently rest between sets and exercises.