Equestrian style riding places a physiological demand on both the horse and the rider. Quantifiable research information is available related to the increase in the equine physiological response to various gait patterns. Limited research information is available related to the response of the rider, with even less relative to the young rider. The purpose of this study was to examine the physiological response of the rider during various equine gait patterns and riding styles. A protocol was created that would elicit a graded increase in the rider's physiological response. The rider heart rate (HR) at the end of each stage was used to assess the graded increase. Following formal written consent, five experienced young female subjects (12-14 years) were monitored each minute using a Polar HR monitor. Riders had participated in formal lessons for three or more years, with all riders required to have “hunt seat” experience. Methods. A pre-riding HR was taken following five minutes on a stationary horse. The protocol developed consisted of nine, three minute stages; walk (W1), sitting trot (ST), walk (W2), posting trot (PT), walk (W3), sitting canter (SC), walk (W4), posting canter (PC), and final walk (W5). Results. The pre-riding average HR was 89.9 bpm. Rider HR increased gradually during the W1 stage to 95.1 bpm. The HR response during walk recovery stages were not different from W1 HR response (W2 = 95.8, W3 = 100.2, W4 = 99.4, and W5 = 107.1 bpm). Each gait and riding style change produced increases in the mean HR (ST = 117.4, PT = 123.6, SC = 137.8, and PC = 142.2 bpm), with PT, SC, and PC conditions producing significantly greater (p < .05) HR responses relative to the initial walk (W1). The highest HR response occurred during the posting phase of each gait change with the largest HR change occurring during the final stage of the PC. Conclusion. Many individuals outside of equestrian riding sports believe that the rider experiences limited physiological stress during participation. The information acquired through this protocol appears to provide evidence of increased physiological stress with increased equine cadence and posting riding styles. Static muscle stabilization of the spine and lower extremities during sitting and dynamic muscle contractions during posting could be the cause for the increased HR response. Riding instructors need to consider the additional physiological demand of riding during skill acquisition and performance based equine events.Keyword(s): exercise/fitness/physical activity, youth sports