Sprint and endurance power and ageing: an analysis of master athletic world records

Abstract

Human physical performance is notably reduced with ageing. Although the effects of ageing are often compounded by disuse, the study of master athletes provides an opportunity for investigating the effects of ageing per se. It is often held that sprinting is more affected than endurance performance. However, past analyses of master athletic world record data have yielded opposite observations. We argue here that our understanding of these data improves by considering how, biomechanically, metabolic power is related to athletic performance. In line with earlier studies, our analysis showed that running speed declines with age in a more pronounced way for endurance events than for sprinting events, confirming former studies. However, when assessing the metabolic power required to achieve the running world records, sprint and endurance events show a relatively uniform decline with age across the different events. This study has reconciled formerly conflicting scientific results and improves our understanding of the ageing process. However, it is unclear as to which are the governing mechanisms that cause the different systems in our body, responsible for sprinting and for endurance performance, to be affected by ageing in a remarkably uniform way.

Figure 1

World record running speed as a function of age for the men's outdoor events. (a) Polynomial fits of mean running speed v. A clear-cut decline in v can be appreciated for all running distances, which seems to be aggravated beyond the age 70. (b) Relative running speed ω, i.e. speed relative to the age-specific world record for 100 m. By definition, ω_D(A)=1 for 100 m at all ages A, and also ω_D(A)=1 for all distances D at age 40. Curves for 400 m and longer races are always below 1. This decline becomes more prominent with age, suggesting that endurance performance is affected by age more than sprinting.

Figure 2

Metabolic power required to achieve the running velocities in figure 1, again as a function of age in the men's outdoor world records. (a) Metabolic power (ER) in absolute terms. The curves were computed from the curves in figure 1a applying equation (2.4). As in figure 1a, there is a clear cut decline of ER with increasing age for all distances, but here the decline appears to be almost linear. (b) Relative metabolic power ϵ, which, by analogy with figure 1b, gives ER relative to the age-specific ER for 100 m. Up to the age of 80, and contrasting with figure 1b, values for middle- and long-distance events are slightly greater than 1, suggesting a moderate sparing effect for endurance power up to the age of 80, and conversely beyond that age.

Figure 3

Comparison of the age-related declines in ER and in aerobic and aerobic capacity, displayed in (a) absolute terms and (b) relative terms. Anaerobic capacity was identified as the peak power in a vertical jump test (PJump). Here, we used the regression equation from 126 master sprinters (Michaelis et al. 2008). ER_100 m is the metabolic power required for the 100 m sprint world record. Since PJump is an external mechanical power value, it cannot be compared to ER_100 m in absolute terms. However, almost identical relative decline rates can be observed between PJump and ER _100 m. ER_10 000 m, i.e. the metabolic power involved in the 10 000 m race world record, is consistently above the VO₂max regression line found by Wiswell et al. (2001) in a sample of 146 master runners of mixed athletic capabilities. Values from the latter study have been transformed from ml O₂ kg⁻¹ min⁻¹ to W kg⁻¹, assuming a caloric equivalent of 20 J ml⁻¹ O₂. Apparently, the relative decline in (b) is somewhat larger for ER_10 000 m than for VO₂max.