IMPOSING A PACING STRATEGY RESULTS IN SLOWER PERFORMANCES

Hettinga, F. J., De Koning, J. J., Schmidt, L., Wind, N., MacIntosh, B. R., & Foster, C. (2009). Imposing a theoretical optimal pacing strategy compared to self-paced competition in 1500-m speed skating. ** ACSM 56th Annual Meeting, Seattle, Washington, ** Presentation Number 1834.

The purpose of this study was to investigate if a theoretically optimal pacing profile, overriding self-paced strategy, yielded better performance. National level speed-skaters (N = 7) performed a self-paced 1,500 m and a 1,500 m with an imposed pacing strategy. The races were analyzed by obtaining velocity every 100 m and body position every 200 m to calculate total mechanical power output. Together with gross efficiency and aerobic power output, obtained in separate trials, data were used to calculate anaerobic power output profiles. An energy flow model was applied to the 1,500-m self-paced trial and a range of pacing strategies was simulated for each individual by varying the distribution of anaerobic energy over time. Athletes were instructed to skate more like the theoretically optimal pacing profile and resulting performance was compared to self-paced performance.

Confirming previous results, the energy flow model predicted a faster start strategy to be optimal. However, final times of the imposed strategy trials were ~2 seconds slower than self-paced performance. Total power distribution per lap differed, with a higher value over the first 300 m for the imposed strategy. All parameters of anaerobic power distribution over time, described by a mono-exponential equation, did not differ. The effort of a faster first lap resulted in a changed skating position. The summation of increased knee- and trunk-angles resulted in a higher aerodynamic drag coefficient throughout the race.

**Implication.** Without appropriate training, imposing a theoretically optimal pacing profile does not lead to better performance. An imposed fast start has relatively large consequences on speed skating technique, affecting work per stroke and aerodynamics negatively.