Physiological stress responses and horse rider interactions in horses ridden by male and female riders

Traditionally, horse riding has been restricted to men but today equestrian sports are dominated by women. We hypothesised that men and women differ with regard to riding and the response they evoke in their horse. Cortisol and heart rate variability (HRV) were studied in male (n=8) and female riders (n=8) and in horses (n=8) ridden by men and women over a jumping course. Saliva for cortisol analysis was collected, cardiac beat to beat (RR) intervals were recorded and heart rate and HRV variables SDRR (standard deviation of RR interval) and RMSSD (root mean square of successive RR differences) calculated. In another experiment, saddle pressure was compared between male and female riders (n=5 each). Cortisol did not differ between male and female riders and increased in horses (P<0.001) irrespective of the sex of the rider. Heart rate in riders increased from walk to jumping (P<0.001) while HRV decreased (P<0.001) to the same extent in men and women. In horses, heart rate increased (P<0.001) and SDRR and R...