The Effect of Different High-Intensity Periodization Models on Endurance Adaptations

Abstract

. Purpose: This study aimed to compare the effects of three different high-intensity training (HIT) models, balanced for total load but differing in training plan progression, on endurance adaptations. Methods: Sixty-three cyclists (peak oxygen uptake (V O 2peak ) 61.3 T 5.8 mLIkg j1 Imin j1 ) were randomized to three training groups and instructed to follow a 12-wk training program consisting of 24 interval sessions, a high volume of low-intensity training, and laboratory testing. The increasing HIT group (n = 23) performed interval training as 4 Â 16 min in weeks 1-4, 4 Â 8 min in weeks 5-8, and 4 Â 4 min in weeks 9-12. The decreasing HIT group (n = 20) performed interval sessions in the opposite mesocycle order as the increasing HIT group, and the mixed HIT group (n = 20) performed the interval prescriptions in a mixed distribution in all mesocycles. Interval sessions were prescribed as maximal session efforts and executed at mean values 4.7, 9.2, and 12.7 mmolIL j1 blood lactate in 4 Â 16-, 4 Â 8-, and 4 Â 4-min sessions, respectively (P G 0.001). Pre-and postintervention, cyclists were tested for mean power during a 40-min all-out trial, peak power output during incremental testing to exhaustion, V O 2peak , and power at 4 mmolIL j1 lactate. Results: All groups improved 5%-10% in mean power during a 40-min all-out trial, peak power output, and V O 2peak postintervention (P G 0.05), but no adaptation differences emerged among the three training groups (P 9 0.05). Further, an individual response analysis indicated similar likelihood of large, moderate, or nonresponses, respectively, in response to each training group (P 9 0.05). Conclusions: This study suggests that organizing different interval sessions in a specific periodized mesocycle order or in a mixed distribution during a 12-wk training period has little or no effect on training adaptation when the overall training load is the same.

How Does Interval-Training Prescription Affect Physiological and Perceptual Responses?

“…[3][4][5] Understanding this interaction at a mechanistic, physiological level is desirable to maximize adaptive signaling effects for a given physiological load. However, HIIT also demands that athletes self-impose large perceived-exertion loads.…”

“…The current study was part of a 12-week, multicenter, randomized training-intervention study recently described in detail. 5 Details of standard testing procedures and instrumentation have been described previously in our companion paper. 5 …”

“…5 Details of standard testing procedures and instrumentation have been described previously in our companion paper. 5 …”

“…Accumulation of fatigue was not detected at the group level over the 12-week training period. 5 Interval sessions were performed on each subjects own roadracing bicycle mounted on identical Computrainer laboratory ergometers (RacerMate, Seattle, WA, USA) calibrated according to manufacturer specifications and connected to a central PC running dedicated software (PerfPRO Studio, Hartware Technologies). Each subject used the same ergometer throughout the 12-week period.…”

“…Subjects could adjust cycling load electronically with ±3 W precision, and were provided continuous feedback regarding power, cadence, HR, and elapsed time on a large video screen. During interval sessions, subjects were instructed to cycle at their maximal sustainable intensity during all 4 interval bouts (isoeffort) [1][2][3][4][5] such that they completed the prescribed session structure with even or slightly progressive power from first to fourth interval bout. Mean power, HR (mean and peak), rating of perceived exertion (RPE 6-20), 6 and cadence were quantified at the end of each of the 4 interval bouts of a HIIT session.…”