A recent research project examining the impact of exercise on mare reproductive health and embryo transfer may hold clues to improving human fertility in a simple and effective way: timed exercise.
Different levels of exercise were tested
Researchers divided light-horse mares into three groups: no exercise, partial exercise and full exercise. They measured reproductive blood flow and embryo number and quality. Partial exercise mares took 30 minutes of moderate exercise during their periovulatory period and then rested after ovulation for a week. The full exercise mares took 30 minutes of moderate daily exercise throughout their reproductive cycle.
Increased cortisol may affect embryo recovery
Exercise induced greater cortisol concentrations in horses. Cortisol effects reproduction in a negative way. In the horses that exercised, embryo recovery rates were reduced compared to the control group. There was no significant difference in embryo recovery between partial exercise and full exercise groups. Partial exercise mares had the lowest embryo quality score.
Timing is everything
“This led us to conclude that exercise was just as detrimental, if not more so, to the time period just prior to and during fertilization,” said Christopher Mortensen of the University of Florida and co-author of the study.
Technology provides more opportunities which can be optimally timed
For the horse industry, advancing technology has allowed embryo transfer to become a vital part of the horse industry. The same could be said for humans. “What we hypothesize is the reduced hormone concentrations may be having an effect on the mare’s oocytes, meaning they are not as ‘competent’ and have a reduced ability to be fertilized, or if fertilized, compromised embryo development,” stated Mortensen.
Could this be meaningful for women?
“While many studies in women have shown intense exercise can be detrimental to female pregnancy, there are virtually no studies examining maternal exercise and effects on the early developing embryo. Furthermore, there are few studies examining stress and the female reproductive blood flow response,” explained Mortensen.
Source: MedicalNewsToday, Journal of Animal Science
