Aim We aimed to describe the daily variations and time course of changes in resting peripheral oxygen saturation (SpO2 rest) and resting heart rate (HRrest) in a group of elite endurance athletes during a 17-21-day training camp at 1800 m. Methods Twenty-one cross-country skiers (9 women) and 11 biathletes (7 women) participated (mean±sd: age 25.8±3.0 yr; VO2 peak 67.2±6.3 mL·kg-1·min-1). SpO2 rest and HRrest were measured every morning with a finger-clip pulse oximeter and the skiers` personal heart rate monitors, respec tively. Temporal changes in SpO2 rest and HRrest were assessed separately using linear mixed effects models. Time was initially modeled as a continuous variable to assess the slope of each parameter, then as a discrete variable to allow comparisons in the mean change on each day at altitude from day one. Results SpO2rest did not systematically change throughout the training camp (continuous model: b=-0.014, p=0.082; discrete model: p=0.278), neither did HRrest when modeled as a continuous variable (b=-0.076, p=0.114). However, when modeled as a discrete variable, HRrest was significantly lower on days 18 and 19 compared to day one (p< 0.05). Practical applications Measuring SpO2 rest and HRrest are typically recommended to monitor acclimatization to altitude in athletes with an increase in SpO2rest and a decrease in HRrest expected in the initial phase. In our study, however, these parameters did not follow a similar pattern. This might be due to the relatively low altitude, which was chosen to better reflect competition environments in elite endurance sports.
© Copyright 2022 Book of Abstracts. 4th Nordic Winter Sports Conference "Performance in snow sports: Translating science into practice" 3rd-4th October, 2022, Mid Sweden University, Campus Östersund, Sweden. Published by Swedish Winter Sports Research Centre at Mid Sweden University. All rights reserved.