Multivariate allometric scaling of men's world indoor rowing championship performance.

The World Indoor Rowing Championship (WIRC) is based on the time (T) to row a simulated 2500 m on a rowing ergometer. In the WIRC there are separate age categories but only two weight classes: light and heavyweight, thus penalizing those just heavier and those significantly lighter than the cut-off weight. Multivariate allometric scaling (MAS) provides an expression of performance free of the confounding effect of more than one scaling variable. We used MAS to scale T by height (H) and age (A) to create a new index of rowing performance, T*H(-a)*A(-b). Subjects were 148 male competitors from the 1995 WIRC. MAS indicated that T*H*A(-0.06) expresses T free of the confounding effect of H and A. We also scaled T only by H on those subjects, A < 40, (N = 109). Results showed that T*H is an optimal and particularly feasible scaling of T. Use of either convention dramatically changed race results. In conclusion, we recommend use of either the T.H (17 < or = A < or = 39) or T*H*A(-0.06) conventions to adjust WIRC performance in adult males.