Naslov
Can greater muscularity in larger individuals resolve the 3/4 power-law controversy when modelling maximum oxygen uptake?

Autori
Nevill, Alan ; Marković, Goran ; Vučetić, Vlatko ; Holder Roger

Izvornik
Annals of human biology (0301-4460) 31 (2004), 4; 436-445

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
metabolic rate; maximum oxygen uptake; body size; allometric scaling

Sažetak
Background: The power function relationship, MR = a• mb, between metabolic rate (MR) and body mass m has been the source of much controversy amongst biologists for many years. Various studies have reported mass exponents (b) greater than the anticipated 'surface-area' exponent 0.67, often closer to 0.75 originally identified by Kleiber. Aim: To provide a biological explanation for these 'inflated' exponents when modelling maximum oxygen uptake ( max), based on the observations from this and previous studies that larger individuals develop disproportionately more muscle mass in the arms and legs. Research Design and subjects: Cross-sectional. Subjects were 119 professional soccer players from Croatia aged 18-34. Results: Here we confirm that the power function relationship between max and body mass of the professional soccer players results in an 'inflated' mass exponent 0.75 (95% confidence interval from 0.56 to 0.93), but also the larger soccer players have disproportionately greater leg muscle girths. When the analysis was repeated incorporating the calf and thigh muscle girths rather than body mass as predictor variables, the analysis not only explained significantly more of the variance in max, but the sum of the exponents confirmed a surface-area law. Conclusions: These findings confirm the pitfalls of fitting body-mass power laws and suggest using muscle-girth methodology as a more appropriate way to scale or normalize metabolic variables such as max for individuals of different body sizes.

Izvorni jezik
Engleski

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