Allometric Scaling of Uphill Cycling Performance

• Published in: International journal of sports medicine 2008-09, Vol.29 (9), p.753-757
• Main Authors: Jobson, S. A., Woodside, J., Passfield, L., Nevill, A. M.
• Format: Article
• Language: English
• Subjects: Adult; Altitude; Bicycling - physiology; Biological and medical sciences; Ergometry; Exercise Test; Exercise Tolerance - physiology; Fundamental and applied biological sciences. Psychology; Humans; Male; Muscle Contraction - physiology; Muscle Strength - physiology; Muscle, Skeletal - physiology; Oxygen Consumption - physiology; Pilot Projects; Task Performance and Analysis; Training & Testing; Vertebrates: body movement. Posture. Locomotion. Flight. Swimming. Physical exercise. Rest. Sports
• ISSN: 0172-4622; 1439-3964
• DOI: 10.1055/s-2007-989441

Abstract Previous laboratory-based investigations have identified optimal body mass scaling exponents in the range 0.79 – 0.91 for uphill cycling. The purpose of this investigation was to evaluate whether or not these exponents are also valid in a field setting. A proportional allometric model was used to predict the optimal power-to-mass ratios associated with road-based uphill time-trial cycling performance. The optimal power function models predicting mean cycle speed during a 5.3 km, 5.4 % road hill-climb time-trial were (V˙O 2max  · m −1.24 ) 0.55 and (RMP max  · m −1.04 ) 0.54 , explained variance being 84.6 % and 70.5 %, respectively. Slightly higher mass exponents were observed when the mass predictor was replaced with the combined mass of cyclist and equipment (m C ). Uphill cycling speed was proportional to (V˙O 2max  · m C −1.33 ) 0.57 and (RMP max  · m C −1.10 ) 0.59 . The curvilinear exponents, 0.54 – 0.59, identified a relatively strong curvilinear relationship between cycling speed and energy cost, suggesting that air resistance remains influential when cycling up a gradient of 5.4 %. These results provide some support for previously reported uphill cycling mass exponents derived in laboratories. However, the exponents reported here were a little higher than those reported previously, a finding possibly explained by a lack of geometric similarity in this sample.