In a convenience sample of healthy men from a non-clinical setting, semen volume and sperm motility decreased continuously between 22-80 years of age, with no evidence of a threshold.

In a convenience sample of healthy non-smoking men from a non-clinical setting, higher antioxidant intake was associated with higher sperm numbers and motility.

Quantitative analysis of sperm motion indicates that as men age, they produce fewer motile sperm, which are able to travel less along a linear path, thus covering less forward distance per unit time. These findings may have fertility implications for men who choose to delay fatherhood.