Testosterone is often referred to as the “male sex hormone” because although women have a small amount of testosterone in their bodies, men’s levels are far greater. In men, this hormone is produced in the testicles, and its primary function is to ignite the male sex drive and to produce sperm.
How are Exercise and Testosterone Levels Related?
Compromised testosterone levels can cause lack of energy, low libido, poor sexual performance and even erectile dysfunction. Testosterone also plays a role in maintaining bone density, red blood cell production and muscle mass. Although certain types of exercise can boost testosterone, research shows that an overzealous exercise habit can actually lower your testosterone levels.
Both men and women can suffer the adverse effects of too much exercise. When a woman’s hormones levels are compromised by excessive exertion, she usually will experience amenorrhea, or absent periods. When a man experiences similarly compromised hormone levels, the effects may not be immediately apparent, making men more prone to over-exercising without even realizing it.
How Much Is Too Much Exercise?
It has been found that the primary form of exercise that reduces testosterone levels in men is long-distance running. According to a study done at the University of British Columbia and published in the British Journal of Sports Medicine, men who ran more than 40 miles per week had testosterone levels that were one-fifth lower than men who ran shorter distances.
That’s not the only study laying out evidence that too much exercise is bad for your hormones. A University of Melbourne study showed that running for less than two hours increased testosterone levels, however running for two hours or more suppressed testosterone. This essentially shows an inverse relationship between running and testosterone. It’s crucial to strike a balance between getting the training results you want, and avoiding overexertion and the negative side effects that come with it.
Yet another study, carried out in Brazil at the Federal University of São Paulo, examined testosterone levels of twenty men before and after running a marathon. After the marathon, the men’s testosterone levels were approximately 50 percent lower than their normal baseline levels—a huge decrease. This could have severe repercussions for those who run marathons on a regular basis, especially if they train long-distance in preparation for those marathons.
The most likely explanation for why too much exercise decreases testosterone is that cortisol levels are chronically elevated in athletes who train in endurance. In the aforementioned study from Brazil, cortisol levels more than doubled after the men ran the marathon, and remained higher than normal for the next twenty-four hours. Cortisol is a hormone produced in response to stress, and chronically high cortisol levels can cause adverse effects on the body, including fatigue and low libido. Some researchers have hypothesized that long-distance running even disrupts communication between the body’s hormone glands and the brain.
Making Exercise Work for You, Not Against You
Nevertheless, running is an excellent source of exercise, and it can be very enjoyable for those who find it pleasant. If you can’t or don’t want to give up running as your primary form of exercise, simply set limits for yourself in order to avoid decreasing your testosterone levels. Avoid running for more than an hour or two at a time, or more than forty miles per week. One study done at the University of Pittsburgh found that running for 15 to 60 minutes actually elevates testosterone levels.
Other forms of exercise may increase your testosterone levels more than moderate running. Consider implementing weight training, as lifting weights is proven to trigger testosterone release. In general, large compound movement exercises are best for increasing testosterone. As with long-distance running, too much weightlifting can harm your hormone levels, so keep your sessions under 60 minutes.
For aerobic exercise, you may want to shift your focus from endurance and distance to intensity. Short intervals of high-intensity exercise elevate your testosterone levels and are great for your heart. An example of this form of exercise would be to sprint for a few minutes, walk for a minute and then sprint again.
For libido support, it’s a good idea to supplement your exercise routine with other health practices such as a healthy diet, getting enough sleep and avoiding substances such as tobacco and alcohol. Natural supplements such as ginseng, maca, fenugreek and ginger can also help support a healthy sex drive.