Portable PSG for sleep stage monitoring in sports: Assessment of SOMNOwatch plus EEG

Abstract

Current sport-scientific studies mostly neglect the assessment of sleep architecture, although the distribution of different sleep stages is considered an essential component influencing an athlete’s recovery and performance capabilities. A mobile, self-applied tool like the SOMNOwatch plus EEG might serve as an economical and time-friendly alternative to activity-based devices. However, self-application of SOMNOwatch plus EEG has not been validated against conventional polysomnography (PSG) yet. For evaluation purposes, 25 participants (15 female, 10 male; M_age = 22.92 ± 2.03 years) slept in a sleep laboratory on two consecutive nights wearing both, conventional PSG and SOMNOwatch plus EEG electrodes. Sleep parameters and sleep stages were compared using paired t-tests and Bland–Altman plots. No significant differences were found between the recordings for Sleep Onset Latency, stages N1 to N3 as well as Rapid Eye Movement stage. Significant differences (Bias [95%-confidence interval]) were present between Total Sleep Time (9.95 min [−29.18, 49.08], d = 0.14), Total Wake Time (−13.12 min [−47.25, 23.85], d = −0.28), Wake after Sleep Onset (−11.70 min [−47.25, 23.85], d = −0.34) and Sleep Efficiency (2.18% [−7.98, 12.34], d = 0.02) with small effect sizes. Overall, SOMNOwatch plus EEG can be considered a valid and practical self-applied method for the examination of sleep. In sport-scientific research, it is a promising tool to assess sleep architecture in athletes; nonetheless, it cannot replace in-lab PSG for all clinical or scientific purposes.

Keywords:

• Polysomnography
• self-application
• athletes
• frontal derivation
• electrodes
• electroencephalography

Acknowledgements

The authors would like to thank all study participants and student assistants for their contribution to the study. A special thanks goes to Prof Dr Thorsten Schäfer for his help with the night scorings.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The study was initiated and funded by the German Bundesinstitut für Sportwissenschaft and realised within “RegMan – Optimization of Training and Competition: Management of Regeneration in Elite Sports [grant number: IIA1-081901/12-20]”.