Physical activity, heart rate variability–based stress and recovery, and subjective stress during a 9-month study period - Föhr, Tiina; Tolvanen, Asko; Myllymäki, Tero; Järvelä-Reijonen, E.; Peuhkuri, K.; Rantala, S.; Kolehmainen, M.; Korpela, R.; Lappalainen, Raimo; Ermes, M.; Puttonen, S.; Rusko, Heikki; et al. (Wiley-Blackwell Publishing, Inc.; Scandinavian Foundation of Medical Science in Sports, 2017)