Research Accolade for Dr Steffi Colyer and Dr Aki Salo
News

A recent article by Dr Steffi Colyer and Dr Aki Salo in collaboration with Dr Ryu Nagahara (from the National Institute of Fitness and Sports in Kanoya, Kagoshima, Japan) has been selected as the Editor’s Choice for July 2018 in the prestigious Scandinavian Journal of Medicine and Science in Sports.
This article about sprinting uniquely demonstrates how the force production demands for the athletes shift during acceleration. The National Institute of Fitness and Sports in Kanoya, Kagoshima, Japan, has an unprecedented 54 force plates under the running track. Thus, it was possible to collate information (entire force production waveforms) from all steps during 50m sprints. These data were then innovatively analysed using Statistical Parametric Mapping to find more detailed information than ever before.
During the earlier steps out of the starting blocks, the differentiating factor across the sprinters was the forces produced in the middle and latter parts of the contact. These were the phases when the athletes’ concentric (propulsive) force production was the key. The key phases of force production started to shift earlier and earlier in the contact across the acceleration, i.e. when the athletes had to tolerate the eccentric (braking) impact of hitting the ground. The emphases of the strength and conditioning training required to improve these varying force production capabilities are partly conflicting. Thus, this work demonstrates the complexity of preparing the athletes for the seemingly simple task of ‘just’ sprinting in a straight line.
The full article can be read here.

Figure: Entire horizontal force waveforms curves for 28 athletes across 24 consecutive sprint ground contacts. Red areas indicate phases of stance across which positive relationships were observed with better performance and demonstrate how the important parts shifted earlier during the acceleration.
Reference: Colyer, S.L., Nagahara, R. and Salo, A.I.T. (2018). Kinetic demands of sprinting shift across the acceleration phase: novel analysis of entire force waveforms. Scandinavian Journal of Medicine and Science in Sports, 28 (7), 1784-1792.