Maintenance work on the ZORA database servers is scheduled for Thursday 25th July 2019 from 19:00-20:00. During this period ZORA and JDB will not be available. Thank you for your understanding.
Herzig, David; Testorelli, Moreno; Olstad, Daniela Schäfer; Erlacher, Daniel; Achermann, Peter; Eser, Prisca; Wilhelm, Matthias (2017). Heart rate variability during deep sleep offers a time-efficient alternative to morning supine measurements - a study in world class alpine skiers. International Journal of Sports Physiology and Performance, 12(5):648-654.