*Department of Physiology, McGill University, and †Centre for Clinical Epidemiology and Community Studies, Montreal, Quebec, Canada
Received June 7, 1999; accepted August 9, 2000.
Address correspondence and reprint requests to Ian Shrier, MD, Centre for Clinical Epidemiology and Community Studies, 3755 Cote Sainte Catherine Road, Montreal, Quebec H3T 1E2, Canada.
For many years, football coaches, Olympic athletes, and even Muhammad Ali have advocated sexual abstinence the night before an athletic event. 1 Marty Liquori, one the world's number one-ranked 5,000-meter runner believes that “Sex makes you happy, and happy people don't run a 3:47 mile.”2 Marv Levy, head coach of the Buffalo Bills, insisted that the team be separated from their wives before their appearance in four Super Bowls; a policy that apparently was not successful (four losses out of four Super Bowls). On the other hand, there are also plenty of anecdotal stories of athletes who claim to have benefited from sex the night before an event. Both U.S. track star David Wottle and Canadian downhill skier Karin Lee Gardner attribute their Olympic gold medals in part to their “pre-race preparation.”2 As legendary New York Yankees manager Casey Stengel put it, “It's not the sex that wrecks these guys, it's staying up all night looking for it.” Considering the controversy surrounding the topic, the objective of this editorial is to summarize the literature on whether sex the night before competition affects performance, and to suggest possible future areas for research.
The long-standing myth that athletes should practice abstinence before important competitions may stem from the theory that sexual frustration leads to increased aggression, and that the act of ejaculation draws testosterone from the body. 1 In actual fact, sex could alter performance through either physiological or psychological factors. To answer this question, we searched SportDiscus (1975–1988/1989, key words: Coitus and Sexual Intercourse) and MEDLINE for relevant articles. Of the 31 articles we retrieved, only 3 were scientific studies (all physiological). All of these studies suggested that sex the night before competition does not alter physiological testing results. For instance, 14 married male former athletes were given a maximum-effort grip strength test the morning after coitus, and the same test following at least 6 days of abstinence. 3 The results suggested that strength and endurance of the palmar flexing muscles are not adversely affected by sex the previous night. An unpublished follow-up to this study was conducted by researchers at Colorado State University on 10 fit, married men, ages 18–45 years (cited in ref. 4). In their tests for grip strength, balance, lateral movement, reaction time, aerobic power (stair-climbing exercise), and VO2max (treadmill test), the results did not change with sexual activity. Finally, the results from a 1995 randomized cross-over study suggested that sexual intercourse 12 hours prior to the test had no significant effects on maximal aerobic power, oxygen pulse, or double product. 5
Based on the results of these studies, one might conclude that sexual activity the night before competition would not affect performance. However, each of the above-mentioned studies focused on the physiological effects of precompetition sex, which would only be expected to decrease performance if the activity led to exhaustion. Considering that normal sexual intercourse between married partners expends only 25–50 calories (the energy equivalent of walking up two flights of stairs), 6 it is doubtful that sex the previous night would affect laboratory physiological performance tests.
Remembering that the original hypothesis suggested that performance would only be affected through a change in aggression, researchers really should have measured variables that are affected by aggression (e.g., motivation, alertness, and attitude toward competition). According to the current “inverted U” sport psychology hypothesis, 4 there is an optimal level of alertness/anxiety before a competition, and a poor performance will result from either being too anxious or not alert enough. If athletes are too anxious and restless the night before an event, then sex may be a relaxing distraction. If they are already relaxed or, like some athletes, have little interest in sex the night before a big competition, then a good night's sleep is all they need. This theory predicts that the results will be dependent on individual preferences and routines. The night before an important race is not a good time for drastic changes in routine. Consistency is the key.
Clearly there is a need for more research on the topic of sexual activity and athletic performance. However, any research will have difficulty controlling factors related to such sexual behavior such as the time of day, frequency and duration of sexual activity, behavior of subjects between data collection, diet, fatigue, stress, and individual response to sexual activity. Anshel also poses a question worth considering: “How valid are test results when a natural activity such as coitus becomes a required act occurring within a specific time period?”7 In addition, results may be dependent on the sexual partner. For instance, heart rate and blood pressure responses are different if sex is with a spouse of 10 years, compared to a new partner or in strange surroundings. 8 Therefore, any future research will have to control for interindividual variation of the above-mentioned variables with a randomized design, or at least control for differences at the analysis stage.
Finally, the inverted U hypothesis for alertness/anxiety suggests that the performance of some people will improve with sex the night before competition (i.e., responders) and the performance of others will be hindered (i.e., nonresponders). If true, a randomized controlled trial may not be able to detect any differences. For instance, if the “truth” is that 50% of the population improves with sex the night before a competition and 50% is hindered by sex the night before competition, a randomized controlled trial will show that on average there is no effect. Therefore, the best way to test the hypothesis is with a repeated-measures, cross-over design in which the same athletes are tested several times following abstinence, and several times following sex the night before competition. This would allow one to determine not only if sex the night before competition affects performance in certain individuals, but also if there are indeed “responders” and “nonresponders.”
1. Krieger L. Scoring before a big event. Winning 1997; 1:88–89.
2. Bloom M. The sex factor. Runner's World 1994; 11:71–74.
3. Johnson W. Muscular performance following coitus. J Sex Res 1968; 4:247–248.
4. Thornton J. Sexual activity and athletic performance: is there a relationship? Phys Sport Med 1990; 18:148–153.
5. Boone T, Gilmore S. Effects of sexual intercourse on maximal aerobic power, oxygen pulse, and double product in male sedentary subjects. J Sports Med Phys Fitness 1995; 35:214–217.
7. Anshel M. Effects of sexual activity on athletic performance. Phys Sports Med 1981; 9:65–68.
8. Bohlen J, Held J, Sanderson M, et al. Heart rate, rate pressure point, and oxygen uptake during four sexual activities. Arch Intern Med 1984; 144:1745–1748.