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Purpose: The purpose of this study was to examine upper-body repeated sprint performance, physiological responses, and the relationships to technique and muscle co-ordination. Methods: Twelve male elite cross-country skiers (body mass: 75.4 ± 7.1, VO2max: 73 ± 4) were tested for repeated sprint ability during 8·8-s maximal poling with 22-s breaks sprint using a modified poling ergometer. Total mean power (i.e. mean power of all sprints added together) and the sprint decrement (i.e. difference in percent between total mean power and best single sprint power times 8) determined performance. Applied forces were measured with a force cell, the movement frequencies and velocity of the movement using high-speed infrared cameras, muscle activation by surface electromyography of biceps and triceps, oxygen consumption was continuously measured breath by breath and blood lactate in the breaks between each sprint. Furthermore, peak power was determined from the first 8-s sprint and VO2peak during a 3-min all-out ergometer poling test. Results: The average total mean power was 2246 ± 387 W. The average sprint decrement was 11.7 % after eight sprints. Poling rate did not change, while power per stroke decreased during the eight sprints (p |
