En validitetsstudie på beeptestet : avseende maximal aerob kapacitet för elitishockeyspelare

Sammanfattning: Introduction: This study aimed to investigate the validity and reliability of the 20m multistage shuttle run test (MST) for elite ice hockey players as a predictor of the maximal aerobic capacity and the how the result is affected by the players age, aerobic and anaerobic capacity, body composition and test surface. The purpose of this was to find out the potential of the 20-m shuttle run test as a measuringtool for the maximal aerobic capacity in frequent testing periods during the season. It is very interesting to be able to administer this easily because the competative phase of the season is very long compared to the pre-seasonal phase and earlier studies have shown that the aerobic capacity is being lowered during this competative phase of the season for elite icehockey players. Methods: 34 elite ice hockey players participated in this study (20.0±3.6 yrs, BMI 24.2±1.6 and VO2-max 58.0±4.8 ml O2•kg-1•min-1). During 3-5 days they underwent 2 MST tests (wood and rubber surface), treadmill running with VO2-max assessed with open-circuit technique, Wingate10% and FFM-assessment with underwater-technique. Blood-lactate was sampled and analyzed with YSI-technique during all tests except the Shuttle-run-test on wood surface. Results: predicted aerobic capacity on the MST was (n=34) 57.6±2.7 ml O2•kg-1•min-1 with a correlation R=0.52 vs. treadmill. The aerobic capacity vs. missprediction was as strong as R=-0.83. The results showed that 13 of 15 subjects with an aerobic capacity lower than 58 ml O2•kg-1•min-1 were overpredicted on the shuttle-run test and 17 of 19 subjects over 58 ml O2•kg-1•min-1 were underpredicted. The correlation between age and missprediction was R=0.62. This can partly be related to other physiological factors such as, for example, peak-power (W) vs. missprediction was R=0.62 and BMI vs. missprediction was R=0.49. Significant differences (p<0.05) between the overestimated and underestimated group were found in: age, length, weight, BMI, FFM, aerobic capacity, concentration of lactate in all tests, peak-power (W) and RPE (Ratio of Perceived Exertion) in lower body extremities in the MST on rubber floor. Test-retest (n=5) for the MST showed the error of method to be 2.05%. Discussion: The MST has high reliability, but our conclusion is that the test can not be used for individual training guidance under any phase of the season due to its low correlation for the aerobic capacity. The study shows that the missprediction depends on so many variables that it is impossible to recalculate the MST formula on a general basis for elite ice hockey players. If one wants this, it must be done for every unique group or team due to its specific characteristics.