字幕表 動画を再生する 英語字幕をプリント With over 100,000 condoms ordered in 2010 for the Vancouver Winter Olympics, it's obvious — a little extra physical activity goes on during the games. But does this sexual excitement before competition influence an athlete's performance? Many ancient civilizations, including the Greeks, believed that semen was divine and contained a man's strength. Today, some athletes hold the belief that sexual frustration, driven by abstinence, ultimately increases aggression, which is valuable for many sports. Testosterone, in particular, is responsible for aggression and sexual desire in both men and women and there has long been the belief that ejaculation draws testosterone from the body. Muhammad Ali, for example, wouldn't make love for six weeks before a fight. But modern science sees things differently. In fact, many studies have shown the exact opposite. Testosterone increases after sex. Go without for three months and testosterone drop to levels near that of a child. So, from a biological perspective, sex may actually increase performance, particularly in sports where a bit of extra aggression could be the deciding factor. Like ski-cross, short track speed skating, or, of course, hockey. So, what about sex tiring the body out? The honest truth is that the average sex session burns only about 50 calories, the equivalent to running up a few flights of stairs. On the contrary, studies have found that sex the night before has no noticeable effects on strength, power and endurance, or any other fitness variables. Though sex has been documented to trigger the release of pain blockers in the brain. These can help modulate chronic pain with effects lasting upwards of 24 hours. The biggest unknown lies in the psychological effects, which is much harder to study and may actually play a bigger role in major competitions. An athlete's best performance is achieved with a particular balance of alertness and anxiety. Of course, staying up all night chasing sexual escapades tips the scales against alertness the next day. On the other hand, sex can be a great stress release for nervous athletes, while other personalities simply desire more focus and concentration, in which case, a good night's sleep is ideal. At the end of the day, science says it depends on how sex affects each individual. If you need that extra kick of testosterone, then you just might want to get your game on a night early. Don't forget! We have a new video out every day during the Olympics. Can't wait? Our amazing partners at the CBC already have five of the videos up now for you to binge on. Just head to cbc.ca/olympics/ScienceSays to watch them before anyone else. Link in the description. But we also want to know your questions for this special series. Use the hashtag #ScienceSays and let us know your burning Olympic questions. And subscribe for more awesome science videos!