The importance of reaction time to the starting signal on race results in elite motorcycle speedway racing.

The study aimed to determine whether the reaction time (RT) to the starting signal has an impact on the points scored by elite male motorcycle speedway riders, or whether it depends on the starting position (gate). Differences among junior and senior riders, and how it changes during a single match (15 heats) and in the subsequent phases of the competitive season (the main and knockout phases) were investigated. The database of reaction times to the starting signal obtained by motorcycle speedway riders was collected from a mobile application called PGE Ekstraliga ver. 1.0.66 (PGE Ekstraliga, Warsaw, Poland). The database included 1.261 results obtained by 65 male riders (age 25.9 ±7.6 years), competing in the highest league in Poland (PGE Speedway Ekstraliga) in the 2021 competitive season. Reaction time was measured using the Pegasus Speedway © telemetry system (Black Burst, Warsaw, PL). Riders scoring 3 points during a heat had the fastest reaction time (F(3,1257) = 8.90, p<0.001, η2 = 0.02), but RT did not influence the final result of the match (p<0.130). The times differ depending on the occupied starting position (F(3,1257) = 6.89, p<0.001, η2 = 0.02), with the fastest RT in the inner position-A compared to the B (p<0.05) and C (p <0.001) positions. Senior riders showed significantly faster RT (0.246s) compared to junior ones (0.258s) (p<0.001). The width of the starting line affects the reaction time (F(3,1257) = 7.94, p<0.001, η2 = 0.02). In the last (15th) heat of the match, RT was the fastest. The fast reaction time during the start affects the scoring of more points in a heat but depends on riders' experience, the starting position and the straight width of the motorcycle speedway stadium. Coaches should pay attention to these factors when programming training measures.