Effects of simulated high-altitude living low-altitude training on the exercise abilities of adolescent boxers

Abstract

BACKGROUND: This study aimed to determine the effects of high-altitude living low-altitude training on the athletic performance and metabolic indexes of adolescent boxers by using a hypobaric cabin to simulate hypoxia in high-altitude environments.METHODS: Male adolescent boxers (n=16; control: n=8, living and training at low altitude [LOLO]; experimental: n=8, living at high altitude and training at low altitude [HILO]). The study period was 5 weeks (35 days) for both groups: baseline, week 1, week 2, week 3, week 4, and week 5 (post-training) representing the time point prior to, the first week, second week, third week, fourth week, and the week after training. Participants in the experimental group, slept in a high-altitude environment (2000m) simulated using an altitude-training hypobaric cabin. Blood indexes (erythrocyte count, hemoglobin, hematocrit, blood urea, creatine kinase), functional indexes (longitudinal jump, grip strength, eyes-closed one-foot standing, selective reaction time, 30-second sit-ups, 30-second push-ups, 30-second squats), and endurance indexes (lactate threshold, power) were assessed.RESULTS: In the HILO group, with respect to baseline, erythrocyte count, hemoglobin level, and hematocrit level increased (week 1); hemoglobin level remained high (week 2), decreased (week 3), and increased (week 4). Blood urea concentration increased to 6.11 ± 0.59 mmol/L in week 2 (P < 0.05); creatine kinase concentration increased to 310.75 ± 112. 21 U/L in week 3 (P < 0.01). Upper and lower limb strength increased in week 5, while the number of squats performed in 30 seconds (lower limb strength) decreased 6.87% in week 4 (P < 0.05), and the grip strength (upper limb strength) decreased 11.35% in week 4 (P < 0.05). The lactate threshold of the experimental group increased.CONCLUSION: Adolescent boxers who lived in high-altitude conditions and trained in low-altitude conditions for 4 weeks exhibited improved blood oxygen transport capacity, upper limb strength, and speed endurance, which indicate that exercise ability improved.