Acute Exposure to Normobaric Hypoxia Impairs Balance Performance in Sub-elite but Not Elite Basketball Players

Abstract

Although high and simulated altitude training has become an increasingly popular training method, no study has investigated the influence of acute hypoxic exposure on balance in team-sport athletes. Therefore, the purpose of this study was to investigate whether acute exposure to normobaric hypoxia is detrimental to balance performance in highly-trained basketball players. Nine elite and nine sub-elite male basketball players participated in a randomized, single-blinded, cross-over study. Subjects performed repeated trials of a single-leg balance test (SLBT) in an altitude chamber in normoxia (NOR; approximately sea level) with FiO2 20.9% and PiO2 ranging from 146.7 to 150.4 mmHg and in normobaric hypoxia (HYP; ~3,800 m above sea level) with FiO2 13.0% and PiO2 ranging from 90.9 to 94.6 mmHg. The SLBT was performed three times: 15 min after entering the environmental chamber in NOR or HYP, then two times more interspersed by 3-min rest. Peripheral oxygen saturation (SpO2) and heart rate (HR) were recorded at four time points: after the initial 15-min rest inside the chamber and immediately after each SLBT. Across the cohort, the balance performance was 7.1% better during NOR than HYP (P < 0.01, ηp2 = 0.58). However, the performance of the elite group was not impaired by HYP, whereas the sub-elite group performed worse in the HYP condition on both legs (DL: P = 0.02, d = 1.23; NDL: P = 0.01, d = 1.43). SpO2 was lower in HYP than NOR (P < 0.001, ηp2 = 0.99) with a significant decline over time during HYP. HR was higher in HYP than NOR (P = 0.04, ηp2 = 0.25) with a significant increase over time. Acute exposure to normobaric hypoxia detrimentally affected the balance performance in sub-elite but not elite basketball players.

Examining the Effects of Altitude on Workload Demands in Professional Basketball Players during the Preseason Phase

“…Greater physiological demands were illustrated by higher average heart rates and more time spent at moderate-very-high-intensity zones during altitude sessions. HR data may be impacted by the geographical location, specifically at higher altitudes [33] and in simulated conditions [16]. HR remains elevated after 3-5 days after initial exposure to altitude, compensating for a decrease in stroke volume [34].…”

“…Also, training high and living high include the potential for high-altitude mountain sickness (AMS) caused by reduced air pressure and lower oxygen levels. This is characterized by headaches, nausea, breathlessness, vomiting, and dizziness [35], which affect fatigue and stress values [33], lower limb balance [16], and sleep quality [17].…”

“…Although hypoxic training enhances physical and physiological performance in basketball players, an increase in fatigue and stress values [14], along with reductions in lower limb balance [16] and sleep quality [17], has been reported. Monitoring workloads at altitude is critical to ensure optimal adaptations.…”

The Methodological Quality of Studies Investigating the Acute Effects of Exercise During Hypoxia Over the Past 40 years: A Systematic Review

“…A considerable number of review studies about physical activity during hypoxia exposure have been performed over the past few decades ( Ando et al, 2020 ; Pojskić et al, 2021 ), investigating its physiologic consequences ( Coppel et al, 2015 ; Fernandez-Lazaro et al, 2019 ; Griffiths et al, 2019 ). Exercise training under hypoxia, as part of elite sports training, was established in the late 1960s, as it is advantageous compared to sea-level training to increase oxygen delivery capacity and aerobic exercise capacity ( Park et al, 2016 ).…”