Sex as Exercise

In a world of rising obesity, exercise is becoming an increasing priority. However, the desire to lead a healthy life must often be balanced against the discomfort and strain of physical exercise. Fortunately, scientists have discovered what may be a viable substitute, combining both personal pleasure and strenuous exertion: sex.

Several researchers led by Antony Karelis at the University of Quebec at Montreal examined twenty-one heterosexual couples from the Montreal region, finding that sex may in fact be considered, at times, to be a significant form of exercise (1).

Over the course of a month, couples were told to have sex once a week in their homes, for a total of four sessions; energy expenditure was computed using data from a mini SenseWear armband that each person wore while having intercourse. For control, all of the participants also completed an endurance exercise session which involved a warm-up of five minutes of walking followed by thirty minutes of running on a treadmill (1).

The researchers found that on average, the energy expenditure during sex was 101 kCal, or 4.2 kCal/min in men, and 69.1 kCal, or 3.1 kCal/min in women. Furthermore, the mean intensity of the workout was 6.0 METS (metabolic equivalents) for men and 5.6 METS for women – indicating that the workout was of moderate intensity. During sexual activity men expended an average of 46.7% (SD ± 16.9%) of the energy they expended during the treadmill exercise, after statistically controlling for BMI. Similarly, women expended 46.0% (SD ± 16.6%) of what they expended on the treadmill. In questionnaires that all participants completed after each session of intercourse, about 98% of participants reported that sex was more pleasurable than the treadmill exercise, and 5% reported that sex was more strenuous than the treadmill (1).

Participants were between the ages of 18 and 35, born in Quebec or francophone, Caucasian, exercised more than two hours per week, and had no sexual dysfunctions. They also had to have sexual activity at least once per week, be in a stable and monogamous relationship with their partner for between six and 24 months. The women had to also use oral contraception (1).

This study bears several significant improvements over previous ones that similarly examined sexual activity. They were limited to simpler techniques such as measuring heart rate and blood pressure for determining intensity. However, heart-rate and blood pressure are not direct measures of energy expenditure or intensity during sexual activity. Furthermore, previous experiments were generally performed in the normal laboratory as opposed to being performed at home in a couple’s more natural environment. Additionally, equipment used to measure exertion, such as an oxygen mask, likely influenced the ability to have sex (1).

Sex is ubiquitous. It therefore can only be reassuring that this study not only shows that it is highly enjoyable, but also suggests that it may be considered a significant exercise. This study may also have significant implications for healthy lifestyle programs planned by health care professionals.

Reference:

1. F. Julie et al., Energy Expenditure during Sexual Activity in Young Healthy Couples. PloS One. 8, 10.(2013)