Purpose: Cyclists may increase exercise intensity by prolonging exercise duration and/or shortening the recovery period during self-paced interval training, which could impact the time spent near V˙O2max. Thus, the main objective of this study was to compare the time spent near V˙O2max during 4 different self-paced interval training sessions.
Methods: After an incremental test, 11 cyclists (mean [SD]: age = 34.4 [6.2] y; V˙O2max=55.7 [7.4] mL·kg-1·min-1) performed in a randomized order 4 self-paced interval training sessions characterized by a work-recovery ratio of 4:1 or 2:1. Sessions comprised 4 repetitions of 4 minutes of cycling with 1 minute (4/1) or 2 minutes (4/2) of active recovery or 8 minutes of cycling with 2 minutes (8/2) or 4 minutes (8/4) of active recovery. Time spent at 90% to 94% (t90V˙O2max), ≥95% (t95V˙O2max), and 90% to 100% V˙O2max (tV˙O2max) was analyzed in absolute terms and relative to the total work duration. Power output, heart rate, blood lactate, and rating of perceived exertion were compared.
Results: The 8/4 session provided higher absolute tV˙O2max and t95V˙O2max than 8/2 (P = .015 and .029) and 4/1 (P = .002 and .047). The 4/2 protocol elicited higher relative tV˙O2max (47.7% [26.9%]) and t95V˙O2max (23.5% [22.7%]) than 4/1 (P = .015 and .028) and 8/2 (P < .01). Session 4/2 (275 [23] W) elicited greater mean power output (P < .01) than 4/1 (261 [27] W), 8/4 (250 [25] W), and 8/2 (234 [23] W).
Conclusions: Self-paced interval training composed of 4-minute and 8-minute work periods efficiently elicit tV˙O2max, but protocols with a work-recovery ratio of 2:1 (ie, 4/2 and 8/4) could be prioritized to maximize tV˙O2max.
Keywords: cycling performance; endurance training; exercise intensity thresholds; high-intensity interval training; pacing strategy.