Familiarisation and reliability of sprint test indices during laboratory and field assessment

The aim of the study was to assess the reliability of sprint performancein both field and laboratory conditions. twenty-onemale (mean ± s: 19 ± 1 years, 1.79 ± 0.07 m, 77.6 ± 7.1 kg) andseventeen female team sport players (mean ± s: 21 ± 4 years,1.68 ± 0.07 m, 62.7 ± 4.7 kg) performed a maximal 20-metresprint running test on eight separate occasions. four trials wereconducted on a non-motorised treadmill in the laboratory; theother four were conducted outdoors on a hard-court trainingsurface with time recorded by single-beam photocells. trialswere conducted in random order with no familiarisation prior totesting. there was a significant difference between times recordedduring outdoor field trials (oft) and indoor laboratorytrials (ilt) using a non-motorised treadmill (3.47 ± 0.53 vs.6.06 ±1.17s; p < 0.001). the coefficient of variation (cv) fortime was 2.55-4.22% for oft and 5.1-7.2% for ilt. duringilt peak force (420.9+87.7n), mean force (147.2+24.7n), peakpower (1376.8 ± 451.9w) and mean power (514.8 ± 164.4w),and were measured. the cv for all ilt variables was highestduring trial 1-2 comparison. the cv (95% confidence interval)for the trial 3-4 comparison yielded: 9.4% (7.7-12.1%), 7.9%(6.4-10.2%), 10.1% (8.2-13.1%) and 6.2% (5.1-8.0%) for pf,mf, pp and mp and respectively. the results indicate that reliabledata can be derived for single maximal sprint measures,using fixed distance protocols. however, significant differencesin time/speed over 20-m exist between field and laboratoryconditions. this is primarily due to the frictional resistance inthe non-motorised treadmill. measures of force and power duringilt require at least 3 familiarisations to reduce variability intest scores.