The pill and endurance performance – what happened when I stopped taking the pill

If someone had told me 10 years ago that taking the contraceptive pill would significantly decrease my ability to build muscle, recover from hard training and potentially decrease my aerobic capacity I likely would never have started taking the pill in the first place. In this blog post I outline how the contraceptive pill can potentially affect athletic performance and provide details of what it has been like coming off the pill. This is my experience only and you should not make a medical decision based on my experience alone.

Effect of combined contraceptive pill on sports performance

In early March 2020 I read Roar by exercise physiologist Stacy Sims. This book had been recommended to me by several people for years, but I never got around to reading it, mainly because I did not like the cover and I prescribed to the school of thought that the principles of training generally apply equally to men and women and that people who claimed otherwise were generally looking for excuses. If there are differences in how men and women should train, I thought these were severely overstated. I try and read books with an open mind and I did find Stacy Sims quite persuasive.

The book covers how women can adapt their training, nutrition and hydration to their physiology. The chapter ‘Demystifying and Mastering your Menstrual Cycle’ includes a relatively detailed outline on how taking the combined contraceptive pill can affect athletic performance. In my situation, the contraceptive pill I took was Levlen ED. This pill contains 30 micrograms of ethinylestradiol (a synthetic estrogen) and 150 micrograms of levonorgestrel (synthetic progesterone). The pill effectively creates a consistently higher estrogen and progesterone environment in the body, mimicking the later luteal phase of the menstrual cycle. This means female athletes taking the contraceptive pill do not get the benefits of the follicular phase of the naturally occuring menstrual cycle.

Roar was first published in 2016. After doing my own investigations into the research that Stacy Sims cites in her book and more recent research, the studies appear to show the following:

·        A number of studies have shown that taking the contraceptive pill negatively affects the ability of women to gain muscle and strength. One study showed 40% less muscle gain for women taking the contraceptive pill, supporting the findings of previous studies that muscle and strength gain is more difficult for women taking the pill.

·        Taking the combined contraceptive pill increases the core temperature at rest by a third of a degree. This may impact the ability of female athletes to perform well, particularly in hot environments.

·        Women taking the combined contraceptive pill have been shown to have elevated oxidative stress in the body compared to women who do not take the pill.

·        Studies also suggest that taking the pill slows muscle recovery after hard workouts and may reduce aerobic capacity.

Taking the contraceptive pill has other health risks including an increase in risk of blood clots, DVT, high blood pressure and cardiovascular disease. Some studies also suggest taking the contraceptive pill contributes to weight gain and a higher percentage of body fat.

Reasons I started taking the contraceptive pill

I started taking the pill when I was eighteen. It was a convenient method of contraception while at university. At the time I was in the University of Sydney’s Elite Athlete Program for soccer. It was useful to be able to skip taking the sugar pills to essentially never have a period. After I retired from soccer and took up running I continued to skip the sugar pill week if it coincided with an important race. I also enjoyed what I saw at the time as mental health benefits. The pill creates a relatively stable hormone environment. For me, the pill helped with my depression, which I had been managing well in the last year of high school but had really come back in the first year of university. The stable hormones made me feel consistently average, and this was an improvement for my mental health at the time. The headaches and migraines I occasionally got also stopped, though this may have been unconnected to taking the pill.

I was taking the cheapest pill on the market Levlen ED, so there was no financial incentive to stop taking them. Every time I have visited a GP to renew the script not one GP has attempted a conversation about whether this is the best form of contraception for me or raised the risks associated with taking the pill or its potential impact on sports performance. I was hardly going to spend money to go to a sports doctor just to get a script for the pill. Whenever I have seen a sports doctor it has been for injuries and it never occurred to me to ask about the potential effects of the pill on recovery or potentially increasing injury risk.

I essentially took the pill for 10 years to be able to control when bleeding occurred, have a predictable cycle length and have stable levels of estrogen and progesterone.

My experience so far

The first two days not taking the pill I felt nauseous, dizzy and sick in the stomach. This is similar to how I felt when I started taking the pill, but the side effects only lasted two days versus six weeks. After the second day I got a very light ‘false period’ which is the bleeding that occurs due to the drop in artificial hormone levels. By the fourth day I felt really clear headed and alert and was thinking very sharply at work. After two weeks I noticed that I seemed to be recovering more rapidly from session and felt really strong training and running. For example, for squat thrusters I usually use 20-25kg but I managed 10×10 at 30kg in a couple of sessions. With all of these experiences, it is difficult to establish causation, but I think stopping taking the pill contributed to the relatively immediate increase in strength.

I have also been dealing with the stressful situation of ending my lease in Canberra as I am in Adelaide for the foreseeable future. Moving is stressful under normal circumstance, but I left Canberra thinking I would be in Adelaide for one to two weeks. It has been really difficult finding removalists, storage and somewhere to store my car during Coronavirus measures. This is at the same time as being very stressed by my work where I provide legal advice on Coronavirus related matters. Sometimes I find when I am stressed, I will cry over small things and that helps relieve some of the stress. I noticed that since I stopped taking the pill I have had no episodes of crying and I am far more functional.

The negative experiences have been the initial nausea and also a small amount of weight loss which seems to mainly be from my breasts. I have also had what seems like increased hair loss. I have masses of hair, so this is not worrying, but it is noticeable when I sweep the floor.

There is a fluctuation of hormone levels throughout the menstrual cycle, so this has taken getting used to. The first half of the cycle is called the follicular phase, which begins on the first day the period begins. Estrogen is the dominant hormone in this phase and progesterone levels are low. It is during this 14 day phase that training may feel easier and greater strength gains are possible than in the second half of the cycle.

During the follicular phase (the two I have been through so far), I have felt absolutely amazing, recovering quicker than normal and feeling very strong both running and in strength training. I have also felt very clear headed and been able to function generally at a very high level. In my opinion, coming off the pill is worth it just to experience this half of the cycle. Being on the artificially elevated hormones from the pill for 10 years, I missed out on this lower hormone phase.

The second half of the cycle is called the luteal phase and starts after testosterone peaks half way through the cycle which causes ovulation. I found that when the luteal phase started I had another 10 or so days I felt similar to the follicular phase (strong, clear headed and optimistic). When I did get PMS it was mainly in the form of headaches and extreme fatigue. This lasted for only two days. I will happily trade the two days of PMS for all those days of feeling strong and clear headed that I missed out on while taking the pill. Another thing to note is that it can take months for the body to re-establish the menstrual cycle after taking the pill. Although I have a regular cycle length and what seems like regular follicular and luteal phases, I have yet to get any bleeding. This will likely return once my body adapts to the relatively recent change of not taking the pill. I am not concerned about racing or training while menstruating, because I usually only experience light menstruation. Once menstruation begins, the follicular phase has started, and the body is primed for strength and endurance.

It is too early to say whether stopping the pill will make me stronger long term or how and if it will affect racing performances. I am expecting to be performing strongly, particularly as I can now take advantage of lower progesterone levels in the follicular phase. If a race falls on the one or two days I have PMS that is unfortunate, but in training I have run on these days and although uncomfortable, I don’t feel as though this would significantly impact my performance. The hormone profile at this time is similar to my every day when I was taking the pill.

I am not here to convince you not to take the pill! In some cases, the risks of taking the contraceptive pill may be outweighed by the benefits a person is getting from the pill. The pill may be the best contraceptive option for you. Maybe the effects on athletic performance do not bother you in the slightest. The purposes of writing this post is to help get more people thinking and talking about this topic. If you are currently taking the pill, take steps to educate yourself about what you are taking. Don’t be like me and wait 10 years before questioning anything.