Date of Award
Master of Science (MS)
William C. Byrnes
Two distinct studies were undertaken in order to examine the effects that both external weight distribution, and internal, bike-rider interface forces had on cyclists. The first section of the study looked at the bike-rider interface forces, and how they fluctuate during normal cycling; as well as how they vary with changes in rider power output, hand position, and cadence. In order to analyze these changes in isolation, three different studies were undertaken. The studies each examined 10 USAC Category 3 or better riders who were tested for 6 minute trials. Riders were tested with their hands on the tops, drops and hoods, with cadences of 60-90 RPM, and power outputs of 1-4 watts per kg. It was found that for each 1 W/kg power output increase, saddle forces decreased by 5.2 percentage points and bottom bracket forces increased by 3.3 percentage points. Cadence did not affect bike-rider interface forces. Shifting a rider's hands from the hoods to the tops and the drops increased the stem force by approximately 2 and 4 percentage points, respectively. The weight distribution study examined the effect of different bike fitting procedures on the bike-rider system, front/rear wheel, weight distribution. The study compared 13 amateur and 14 professional riders with four different fitting techniques. It was found that the Retül Fit weight distribution was 44.7%/55.3% front/rear and the Body Geometry Fit was 32.5%/61.5% front/rear. It was also found that the professional fit and the self-fit 40.4%/59.6%, and 38.5%/61.5% respectively, are similar (p=.9239).
Carahalios, Adam James, "An Analysis of the Bicycle-Rider Interface Forces in Stationary Road Cycling" (2015). Integrative Physiology Graduate Theses & Dissertations. 43.