SCALING PEAK POWER OUTPUT FOR DIFFERENCES IN BODY SIZE IN WOMEN 301

Abstract

There has been a revival of interest in how physiological and performance variables should be scaled for differences in the size of the body or its exercising segments and it has been demonstrated that non-linear allometric modelling can be used to scale peak power output in men. The purpose of this study was to evaluate the use of such modelling in women. Fifteen women age 22.7 ± 1.6 years, stature 164.3 ± 5.5 cm and body mass 61.8± 5.5 kg (mean ± S.D.) who were fully accustomed to the procedures provided written informed consent and were recruited. Optimised peak power output (OPP) was determined on a friction braked cycle ergometer(Monark 814E) in a procedure that accounts for muscle force-velocity relationships. Lean leg volume (LLV) and lean upper leg volume (LULV) were determined anthropometrically. The OPP was 618 ± 98 W, LLV 4.96± 0.68 l and LULV 3.12 ± 0.48 l. Logarithmic transformations of the measures were used to identify the allometric relationships between OPP and the anthropometric variables. The resulting power functions were: 207.5LLV0.68 (r = 0.585, P = 0.022) and 334.6LULV0.53 (r = 0.514, P = 0.050). Standard errors of the exponents were 0.261 and 0.247 respectively. Neither of the measures satisfied the criterion for the use of simple ratio standards. Both variables were raised to the surface law's exponent of 0.67 and then divided into OPP to produce power function ratios. These were: 211 ± 26 W·l-0.67 for LLV and 289 ± 38 W·l-0.67 for LULV. The results suggest that non-linear allometric modelling can be used to scale peak power output for differences in body size in women.