Sprinting velocity is the product of stride rate and stride length ( Dillman, 1975), and a high ground reaction force and a short ground contact time are associated with a good sprint performance ( Weyand et al., 2000 Korhonen et al., 2003). Success in sprint running requires a short reaction time, fast acceleration, high top velocity and high sprint endurance ( Smirniotou et al., 2008). The performance in running, sprinting ( Ganse et al., 2018a) and javelin throwing ( Ganse and Degens, 2018b) seems to show an accelerated decline after the age of 70 ( Harridge and Lazarus, 2017). Track and field athletics encompasses different disciplines, including throwing and jumping, but the most popular are sprinting and middle- and long-distance running ( Ganse et al., 2018a). While many older people are inactive because they fear incurring an injury, we have shown a low injury risk in healthy master athletes, which does not increase with age or performance ( Ganse et al., 2014). Continuing sports with aging helps to maintain individual independence and reduces the need of acute and chronic care services ( Shephard, 1993). Indeed, physical activity reduces the risk of developing major cardiovascular and metabolic diseases, obesity, falls, cognitive impairments, osteoporosis, and muscle weakness ( McPhee et al., 2016). Exercise is one of the major factors to maintain health ( Kettunen et al., 2006) and mobility in old age. This will not only put our healthcare systems to the test, but also emphasizes the need for interventions to increase health span ( McPhee et al., 2016).
As the increasing life expectancy is not followed by an equal increase in healthy life years, the number of older people with morbidities increases ( Jagger, 2015). The aging society is a major challenge for Western countries in the twenty-first century. The aging-related changes of sprinting kinematics have a minor contribution to the aging-related decline in performance. In conclusion, the kinematics of sprinting differ between sexes and change with age. In 200-m sprint, in addition to age and sex, only hip flexion angle (age: R 2 = 0.506 age + sex adjusted: R 2 = 641 age + sex + hip flexion adjusted: R 2 = 0.655) contributed to performance. While performance was mainly determined by age ( R 2 = 0.501, p < 0.001) and sex (adjusted R 2 = 0.642), hip flexion angle (adjusted R 2 = 0.686) and bending over angle (adjusted R 2 = 0.705) contributed also to performance in 60-m sprint. Bending over angle ( p = 0.004), brake angle ( p = 0.004) and hip flexion angle ( p < 0.001) increased, whereas propulsion angle ( p < 0.001) and leg stiffness angle ( p = 0.001) decreased with age, irrespective of sex. To investigate this, in 199 men (30–89 years) and 81 women (33–76 years), bending over, brake, propulsion, leg stiffness and hip flexion angles were assessed during a sprint stride using high-resolution video analyses. The aim of this study was to assess the influence of age, sex and sprinting kinematics on sprint performance. The sprint performance of master athletes decreases with age, but little is known about possible contributions of changes in sprint kinematics.