Determinants of repeated-sprint ability in females matched for single-sprint performance.
This study investigated the relationship between VO2max and repeated-sprint ability (RSA), while controlling for the effects of initial sprint performance on sprint decrement. This was achieved via two methods: (1) matching females of low and moderate aerobic fitness (VO2max: 36.4 +/- 4.7 vs 49.6 +/- 5.5 ml kg(-1) min(-1) ; p < 0.05) for initial sprint performance and then comparing RSA, and (2) semi-partial correlations to adjust for the influence of initial sprint performance on RSA. Tests consisted of a RSA cycle test (5 x 6-s max sprints every 30 s) and a VO2max test. Muscle biopsies were taken before and after the RSA test. There was no significant difference between groups for work (W1, 3.44 +/- 0.57 vs 3.58 +/- 0.49 kJ; p = 0.59) or power (P1, 788.1 +/- 99.2 vs 835.2 +/- 127.2 W; p = 0.66) on the first sprint, or for total work (W(tot), 15.2 +/- 2.2 vs 16.6 +/- 2.2 kJ; p = 0.25). However, the moderate VO2max group recorded a smaller work decrement across the five sprints (W(dec), 11.1 +/- 2.5 vs 7.6 +/- 3.4%; p = 0.045). There were no significant differences between the two groups for muscle buffer capacity, muscle lactate or pH at any time point. When a semi-partial correlation was performed, to control for the contribution of W1 to W(dec), the correlation between VO2max and W(dec) increased from r = -0.41 (p > 0.05) to r = -0.50 (p < 0.05). These results indicate that VO2max does contribute to performance during repeated-sprint efforts. However, the small variance in W(dec) explained by VO2max suggests that other factors also play a role.
Bishop
David
D
Team Sport Research Group, School of Human Movement and Exercise Science, The University of Western Australia, Crawley, WA, 6009, Australia. dbishop@cyllene.uwa.edu.au
Edge
Johann
J
D000328:Adult; D015308:Anaerobic Threshold; D005080:Exercise Test; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid / Q000378:metabolism; D018482:Muscle, Skeletal / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption; D010809:Physical Fitness / Q000502:physiology*; D011659:Pulmonary Gas Exchange; D013177:Sports / Q000502:physiology*; D013997:Time Factors
D019344:Lactic Acid; D010100:Oxygen