ABSTRACT
The measurement of critical power (CP) has experienced a resurgence of interest in recent years and appears to have useful application to the study of human performance. The purpose of this study was to investigate the relationship between critical power (CP), as determined using an isokinetic swim bench, and middle distance swimming performance (1500m). Twelve male competitive swimmers (age 18.4 + 2.8 years; best time 1024 ± 86.3 s; mean, SD) gave written informed consent and were recruited to the study. The CP was determined on a computer-interfaced isokinetic swim bench (CIISB) which uses force, distance and duration transducers on individual pulley-ropes for right and left arms, to compute work done per stroke and power output. Four all-out effort tests to exhaustion, at different power output settings, were performed with 1 hr recovery. The time limit (Tlim) and total work done (Wlim) for each test were recorded and used to calculate CP, as the slope ‘b’ of the regression equation Wlim = a + b Tlim. All subjects also completed a 1500m front crawl swim time trial (TT1500) on a separate occasion. The mean CP as determined on the swim bench was 120.7 + 4.9 W (mean ± SEM) and mean TT1500 was 1036 ± 22.6 s. The TT1500 was significantly correlated with CP (r=−0.89; p<0.05) and was given by; TT1500 = 1563 – 4.4 CP (SEE,52.1; V%,4.7). These results suggest that CP is a valuable indicator of middle-distance swimming performance in trained swimmers and that it is possible to determine CP using non- invasive techniques in the laboratory with the computer-interfaced isokinetic swim bench.
