ORLANDO, Fla.—Men who engage in moderate exercise have better sperm motility than sedentary men, according to a new prospective study presented at the American Society for Reproductive Medicine annual meeting.
The study, by researchers at Kuramoto Women’s Clinic and Yamaguchi University in Japan, included 215 men who attended an in vitro fertilization clinic in Japan from April 2010 to April 2011 and completed the Godin Leisure-Time Exercise Questionnaire. The men were grouped by their self-reported physical activity measured in metabolic equivalent hours per week (MET-h/w). The MET-h/w was calculated for each man using the frequency of his exercise, its duration, and a MET score for strenuous, moderate, or light exercise. Each participant provided at least two semen samples, which were evaluated for volume, sperm concentration, and sperm motility. Subjects had a mean age of 37.5 years (range 24-59 years). Age and body mass index (BMI) were similar among the groups.
The group reporting moderate exercise had the highest average sperm motility as well as a significantly lower percentage of men with less than 40% sperm motility (14.3%) compared with the other groups. In the group with the lowest MET-h/w, 30.8% of men had sperm motility under 40%; in the group with the highest MET-h/w, 27.1% of men had sperm motility under 40%.
“It is well known that regular exercise is associated with many health benefits, but data on its effects on male fertility are limited,” said lead investigator Masao Murakami, DVM, PhD, a senior research scientist at the women’s clinic. “Today, many subfertile men can be offered a chance to improve fertility via assisted reproductive technologies such as intracytoplasmic sperm injection. However, this only bypasses the problem and, in many cases, the underlying cause may be left unresolved. Therefore, research to understand the lifestyle factors that can potentially affect male fertility may ultimately lead to more satisfactory and cost-effective treatments.”