Four-week experimental plus 1-week taper period using live high train low does not alter muscle glycogen content

This study aimed to investigate the effects of a 4-week live high train low (LHTL; FiO2 ~ 13.5%), intervention, followed by a tapering phase, on muscle glycogen concentration. Fourteen physically active males (28 ± 6 years, 81.6 ± 15.4 kg, 179 ± 5.2 cm) were divided into a control group (CON;n = 5), and the group that performed the LHTL, which was exposed to hypoxia (LHTL;n = 9). The subjects trained using a one-legged knee extension exercise, which enabled four experimental conditions: leg training in hypoxia (TLHYP); leg control in hypoxia (CLHYP,n = 9); leg trained in normoxia (TLNOR,n = 5), and leg control in normoxia (CLNOR,n = 5). All participants performed 18 training sessions lasting between 20 and 45 min [80–200% of intensity corresponding to the time to exhaustion (TTE) reached in the graded exercise test]. Additionally, participants spent approximately 10 h day−1 in either a normobaric hypoxic environment (14.5% FiO2;  ~ 3000 m) or a control condition (i.e., staying in similar tents on ~ 530 m). Thereafter, participants underwent a taper protocol consisting of six additional training sessions with a reduced training load.SpO2 was lower, and the hypoxic dose was higher in LHTL compared to CON (p <  0.001). After 4 weeks, glycogen had increased significantly only in the TLNOR and TLHYP groups and remained elevated after the taper (p <  0.016). Time to exhaustion in the LHTL increased after both...
Source: European Journal of Applied Physiology - Category: Physiology Source Type: research