A. Weydahl et al., SEASONAL-VARIATIONS IN MELATONIN MAY MODULATE GLYCEMIC RESPONSE TO EXERCISE, Perceptual and motor skills, 86(3), 1998, pp. 1061-1062
After a 30-min. standardized bicycle exercise at two times of day in 5
mo, of the year, 62 subjects showed a yearly variation in their glyce
mic response that was about 5 months out of phase with the peak levels
in the light sensitive hormone melatonin, suggesting a reciprocal rel
ationship between melatonin and glucose utilization.