Effects of Intermittent Training on Anaerobic Performance and MCT Transporters in Athletes

Grégoire Millet,Jacques Mercier,Lars R Mc Naughton,David Cameron-Smith,Belle Roels,David J Bentley

doi:10.1371/journal.pone.0095092

Abstract

This study examined the effects of intermittent hypoxic training (IHT) on skeletal muscle monocarboxylate lactate transporter (MCT) expression and anaerobic performance in trained athletes. Cyclists were assigned to two interventions, either normoxic (N; n = 8; 150 mmHg PIO2) or hypoxic (H; n = 10; ∼3000 m, 100 mmHg PIO2) over a three week training (5×1 h-1h30.week−1) period. Prior to and after training, an incremental exercise test to exhaustion (EXT) was performed in normoxia together with a 2 min time trial (TT). Biopsy samples from the vastus lateralis were analyzed for MCT1 and MCT4 using immuno-blotting techniques. The peak power output (PPO) increased (p<0.05) after training (7.2% and 6.6% for N and H, respectively), but VO2max showed no significant change. The average power output in the TT improved significantly (7.3% and 6.4% for N and H, respectively). No differences were found in MCT1 and MCT4 protein content, before and after the training in either the N or H group. These results indicate there are no additional benefits of IHT when compared to similar normoxic training. Hence, the addition of the hypoxic stimulus on anaerobic performance or MCT expression after a three-week training period is ineffective.

Highlights

The effects of intermittent hypoxic exposure or altitude training have been investigated on prolonged endurance performance
No significant differences were observed in peak power output (PPO) or VO2max obtained during the incremental exercise test or performance during the 2 min all-out trial values before the training period between the two training groups (Table 4)
This study was conducted to examine the effects of intermittent hypoxic training (IHT) on anaerobic performance and monocarboxylate lactate transporter (MCT) expression in human skeletal muscle

Summary

Introduction

The effects of intermittent hypoxic exposure or altitude training have been investigated on prolonged endurance performance. There is considerable debate on the use of the different high-intensity hypoxic training methods as intermittent hypoxic training (IHT), which is frequent training of a higher intensity in hypoxia, or repeated sprints training in hypoxia (RSH) to improve endurance performance or repeated sprint ability in normoxia/at sea-level [8,18,25,34,35]. There is some evidence that altitude training can benefit sprinting or other short-term high-intensity performance that requires a substantial anaerobic metabolic contribution [2,7,9,]. Only few scientific studies have examined the effects of IHT on anaerobic performance [27]

Methods

Results

Conclusion