Cyclists and triathletes have different body positions on the bicycle.

Our study evaluated differences in body position on the bicycle for recreational cyclists, competitive cyclists and triathletes. Thirty-six recreational cyclists, 17 competitive road cyclists and 18 competitive triathletes were assessed for body position on their bicycles on a cycle trainer. Images were taken of cyclists/triathletes in static poses with the crank at the 3 o'clock and 6 o'clock positions. Trunk, pelvis, hip, knee and ankle angles, anterior-posterior and medio-lateral positions of the knees in relation to the pedal axis and frontal projected area were measured using ImageJ. Comparison of body position between groups (recreational, competitive road cyclists and competitive triathletes) was conducted using effects sizes (ES). The greatest differences between groups in the measured variables were observed between the triathletes and the other two groups. Smaller differences were observed between competitive and recreational cyclists. Competitive triathletes had greater body forward projection (10% greater trunk flexion and 66% knee anterior position, ES = 2.5 and 1.2, respectively) and less frontal projected area (17%, ES = 1.3) than competitive road cyclists for body position on the bicycle. Both recreational and competitive cyclists sat on their bicycles with their trunks in a more vertical position compared to triathletes. Guidelines for bicycle configuration for triathletes and road cyclists need to consider the body positions during events.