Abstract
Purpose This study assesses the finite work capacity ( W′ ) above critical power (CP) when work rate is reduced during severe intensity exercise and whether reducing work rate immediately prior to task failure allows continued work above CP. Methods 14 cyclists performed three experimental trials. Two consisted of exercising at a fixed work rate (WR) that depleted 70% of W′ in 90 s and 180 s respectively, after which work rate was reduced to CP + 20 W and continued until task failure. The third consisted of exercising at a fixed work rate to achieve task failure in 5 min (P 5 ) when work rate was reduced, and exercise continued until task failure. Work rate was reduced a further two times and continued until task failure. Predicted (WORK PRED ) and actual work above CP (WORK 90 , WORK 180 , WORK P5 ) and predicted (TTE PRED ) and actual time to task failure (TTE 90 , TTE 180 , TTE P5 ) for each of the trials were compared. Results Compared to WORK PRED , total work above CP was greater ( P < 0.05) in all three trials [WORK 90 (+ 5.4 ± 0.7 kJ); WORK 180 (+ 4.3 ± 1.3 kJ); WORK P5 (+ 2.7 ± 0.4 kJ)]. Compared to the respective predicted time, time to task failure was greater ( P < 0.05) in all three trials [TTE 90 (+ 256 ± 38 s); TTE 180 (+ 240 ± 55s); TTE P5 (+ 109 ± 12s)]. Conclusion W′ is not a fixed parameter. When W′ was partially depleted work above CP continued more than predicted. Moreover, when W′ is theoretically 0 kJ, work can continue above CP, if work rate is reduced.