Effect of a previous sprint on the parameters of the work-time to exhaustion relationship in high intensity cycling

The relationships between both metabolic (E) and mechanical (W) energy expended and exhaustion time (t_e), was determined for 11 well-trained subjects during constant load cycloergometric exercises at 95,100,110, 115% maximal aerobic power performed both from rest and, without interruption, after an all-out sprint of 7 s. These relationships were well described by straight lines: y = a + bt_e, where b was taken as the critical power (metabolic and mechanical) that can be sustained for long periods of time, b was unaffected by the exercise conditions and amounted to 82-94% of maximal aerobic metabolic and mechanical power. The constant a was taken as the anaerobic stores capacity in excess of the O₂ deficit. When the test was preceded by the sprint, a (metabolic and mechanical) was reduced to about 60-70% of control values. This reduction was essentially equal to the corresponding E and W output during the sprint. These data support the view that the slope of linear regressions of E and Won te is indeed a measure of the critical power, whereas the y intercept of these same regressions is a measure of the anaerobic capacity.