Sleep quality in athletes under normobaric hypoxia equivalent to 1500 m altitude: A polysomnographic study

Abstract

In the present study, we evaluated the duration of slow-wave sleep (Stage 3 and 4) and total delta power ( B3Hz) in all-night non-rapid eye movement (NREM) sleep electroencephalograms (EEGs) of athletes during normobaric hypoxia at simulated altitudes of 1500 m. Seven male athletes slept for two nights in a normoxic condition and one night in an hypoxic condition equivalent to an altitude of 1500 m. Whole-night polysomnographic recordings, thoracic and abdominal motion, nasal and oral airflow, and blood oxygen saturation (SpO 2 ) were recorded. Visual sleep stage scoring and fast Fourier transformation analyses of EEG were performed using 30-s epochs. Mean and minimum SpO 2 decreased significantly during sleep in the hypoxic condition. Between groups, changes in heart rate, respiratory disturbance measures including apnoea and hypopnoea, slow-wave sleep and total delta power of the all-night NREM sleep EEG were small and non-significant for the hypoxic condition . However, individual difference in time at an SpO 2 below 90% were large in the hypoxic condition, and both slow-wave sleep and total delta power of all-night NREM sleep EEG decreased in three participants who spent a prolonged time below 90% SpO 2 . The present results suggest that monitoring time below 90% SpO 2 is recommended when studying individuals' living-high schedule even under hypoxic conditions equivalent to an altitude of 1500 m.

Sleep in athletes and the effects of Ramadan

“…Unfortunately, given the requirement for specialised technical staff who are needed for both acquisition and scoring of sleeping patterns, the time required to complete testing procedures (e.g. 1 hour setup and 48 hours recording time), and the disturbances from the electrodes, polysomnography investigations are Sleep duration and quality using comprehensive physiologic assessment of brain wave activity, breathing, muscle movement, and oxygenation; analysed by qualified technician Mougin 1991Mougin , 2001Montmayeur 1994;Taylor 1997;Netzer 2001;Kinsman 2002Kinsman , 2003Kinsman , 2005Pedlar 2005;Hoshikawa 2007Hoshikawa , 2010Leger 2008;Gosselin 2009;Davies 2010 Actigraphy sleep duration and quality using movement activity collected from wrist device and analysed using software Straub 2001;Wall 2003;Mauvieux 2003;Richmond 2004Richmond , 2007Montaruli 2009;Fietze 2009;Pontifex 2010;Mah 2011 S80 R. Roky et al underutilised in athletes, except in controlled, laboratory experiments (see references in Table III). Noteworthy, Baekland and Lasky (1966) were among the first to report on polysomnography in athletes and demonstrated a positive relationship between exercise and the amount of slow wave sleep.…”

Sleep quality under mild hypoxia in men with low hypoxic ventilatory response

“…In that study, the subjects revealed lower mean blood oxygen saturation (SpO 2 ) than subjects in previous studies. We subsequently examined slow-wave and other sleep stages and the whole-night delta power of NREM sleep EEG, SpO 2 and respiratory events at a simulated altitude of 1500 m (Hoshikawa et al, 2010). At that lower simulated level the decreases in stages 3 and 4 and whole-night delta power of NREM sleep EEG were small and non-significant.…”