Research exploring rider weight and its impact on the muscles and heart of a pony has recently been published in the International Journal of Equine Science.The study investigated epaxial muscles (those located above the spine) and their sensitivity to pain, as well as heart rate variability (HRV) as a physiological stress factor.The research team, led my Jenna Payne, analysed ridden Exmoor ponies from different age groups. The 10 trekking ponies were aged between 13 and 25.Credit: Freya SmithThree riders took part in the study, a lightweight, middleweight and heavyweight.The ponies completed a trekking route of just over 4km in walk and trot, once a day for three consecutive days with each of the above riders.A pressure algometer was used to determine sensitivity to pain before, immediately after and two hours following the ride. HRV was also recorded at these times.Image by Freya SmithThe data revealed that the ponies aged 17 or younger experienced an increased sensitivity to pain two hours after the ride, for all rider weights. Ponies aged 18 or older experienced a reduced sensitivity to pain immediately following exercise, but increased sensitivity after two hours rest, when ridden by middleweight or heavyweight riders. HRV was not affected by the age of the pony.The team noted that further research is needed with a larger cohort and selection of breeds or types, and longevity of effects. Industry recognition A poster demonstrating the study won a competition at the 2026 Horses Inside Out Conference earlier this year.This years winner, Jenna Payne, produced a poster that was well-researched, interesting, and very timely, given that the rider weight debate and associated welfare issues are at the forefront of many minds, said Gillian Higgins, founder of Horses Inside Out.The Effects of Rider Weight and Pony Age on Epaxial Muscle Pain Sensitivity and Heart Rate Variability in Exmoor Ponies: A Preliminary Study can be read in full in the International Journal of Equine Science.Lead image by Freya SmithRelated contentHow much weight can a horse carry?Veterans: vet advice for adjusting to the senior years and knowing when to ease off on his workloadResearch reveals surprising similarity between horses and beatboxersThe post Impact of rider weight explored in Exmoor pony study appeared first on Your Horse.