OBJECTIVE: To determine the effect of physical activity and sedentary behavior on melatonin levels in a group of rotating shift nurses. METHODS: Physical activity and sedentary behaviors for 118 nurses were recorded during both a day shift and a night shift using activity diaries, and concentrations of urinary 6-sulfatoxymelatonin were analyzed for each shift. RESULTS: During the day shift, energy expended in moderate- and vigorous-intensity physical activity between 3 PM and 7 AM was negatively associated with melatonin levels (P = 0.024). During the night shift, energy expended in sedentary behaviors was negatively associated with melatonin levels (P = 0.008). CONCLUSIONS: Physical activity and energy expended in sedentary behavior are inversely associated with morning urinary melatonin concentrations. Nevertheless, energy expenditure explains a relatively small amount of melatonin variation, perhaps suggesting that peak melatonin is minimally affected by these patterns of physical activity.
OBJECTIVE: To determine the effect of physical activity and sedentary behavior on melatonin levels in a group of rotating shift nurses. METHODS: Physical activity and sedentary behaviors for 118 nurses were recorded during both a day shift and a night shift using activity diaries, and concentrations of urinary 6-sulfatoxymelatonin were analyzed for each shift. RESULTS: During the day shift, energy expended in moderate- and vigorous-intensity physical activity between 3 PM and 7 AM was negatively associated with melatonin levels (P = 0.024). During the night shift, energy expended in sedentary behaviors was negatively associated with melatonin levels (P = 0.008). CONCLUSIONS: Physical activity and energy expended in sedentary behavior are inversely associated with morning urinary melatonin concentrations. Nevertheless, energy expenditure explains a relatively small amount of melatonin variation, perhaps suggesting that peak melatonin is minimally affected by these patterns of physical activity.
Authors: Danilo S Ferreira; Fernanda G Amaral; Caroline C Mesquita; Ana Paula L Barbosa; Camilo Lellis-Santos; Ariane O Turati; Laila R Santos; Carolina S Sollon; Patricia R Gomes; Juliana A Faria; José Cipolla-Neto; Silvana Bordin; Gabriel F Anhê Journal: PLoS One Date: 2012-06-12 Impact factor: 3.240
Authors: Susan Hurley; David O Nelson; Erika Garcia; Robert Gunier; Andrew Hertz; Peggy Reynolds Journal: Int J Health Geogr Date: 2013-08-30 Impact factor: 3.918