The anthropometry of economical running

The influence of anthropometry and body composition on running economy is unclear, with previous investigations involving small relatively homogeneous groups of runners and limited anthropometric/composition measurements. PURPOSE: To comprehensively investigate the relationships of anthropometry and body composition with running economy within a large heterogeneous sample of runners. METHODS: Eighty-five runners (Males (M), n=45; Females (F) n=40), of diverse competitive standard, performed a discontinuous protocol of incremental treadmill running (4 min stages, 1 km·h increments) to establish locomotory energy cost (LEc) of running at submaximal speeds (averaged across 10-12 km·h; the highest common speed < lactate turnpoint). Measurements of anthropometry, including segment lengths, perimeters, masses and moments of inertia (MoI), and body composition were obtained using tape-based measurements and dual-energy x-ray absorptiometry (DXA). RESULTS: Absolute LEc (ABSLEc, kcal·km) was positively correlated with 21 (out of 27) absolute anthropometric variables in both male and female cohorts. Multiple regression analysis revealed that one variable (mean perimeter z-score) explained 49.4% (M) and 68.9% (F) of the variance in ABSLEc. Relative LEc (RELLEc, kcal·kg·km) was also correlated with 5 (M) and 7 (F) normalised anthropometric variables, and regression analysis explained 31.6% (M; percentage bone mass and normalised hip perimeter) and 33.3% (F, normalised forearm perimeter) of the variance in RELLEc. CONCLUSIONS: These findings provide novel and robust evidence that anthropometry and body composition variables, predominantly indicative of relative slenderness, explain a considerable proportion of the variance in running economy (i.e., more slender, lower energy cost). We therefore recommend that runners and coaches are attentive to relative slenderness in selecting and training athletes with the aim of enhancing running economy, and improving distance running performance.