LAURSEN, P. B., C. M. SHING, J. M. PEAKE, J. S. COOMBES, and D. G. JENKINS. Interval training program optimization in highly trained endurance cyclists. Med. Sci. Sports Exerc., Vol. 34, No. 11, pp. 1801–1807, 2002.
Purpose: The purpose of this study was to examine the influence of three different high-intensity interval training (HIT) regimens on endurance performance in highly trained endurance athletes.
Methods: Before, and after 2 and 4 wk of training, 38 cyclists and triathletes (mean ± SD; age = 25 ± 6 yr; mass = 75 ± 7 kg; V̇O2peak = 64.5 ± 5.2 mL·kg−1·min−1) performed: 1) a progressive cycle test to measure peak oxygen consumption (V̇O2peak) and peak aerobic power output (PPO), 2) a time to exhaustion test (Tmax) at their V̇O2peak power output (Pmax), as well as 3) a 40-km time-trial (TT40). Subjects were matched and assigned to one of four training groups (G1, N = 8, 8 × 60% Tmax at Pmax, 1:2 work:recovery ratio; G2, N = 9, 8 × 60% Tmax at Pmax, recovery at 65% HRmax; G3, N = 10, 12 × 30 s at 175% PPO, 4.5-min recovery; GCON, N = 11). In addition to G1, G2, and G3 performing HIT twice per week, all athletes maintained their regular low-intensity training throughout the experimental period.
Results : All HIT groups improved TT40 performance (+4.4 to +5.8%) and PPO (+3.0 to +6.2%) significantly more than GCON (−0.9 to +1.1%;P < 0.05). Furthermore, G1 (+5.4%) and G2 (+8.1%) improved their V̇O2peak significantly more than GCON (+1.0%;P < 0.05).
Conclusion : The present study has shown that when HIT incorporates Pmax as the interval intensity and 60% of Tmax as the interval duration, already highly trained cyclists can significantly improve their 40-km time trial performance. Moreover, the present data confirm prior research, in that repeated supramaximal HIT can significantly improve 40-km time trial performance.