Effects of morning bright light in healthy elderly women: Effects on wrist activity

To investigate the effects of 8000 lux morning bright light in the elderly, home-based motor activity on sleep was monitored for 5 days in 10 healthy women (mean age: 59.7 years old, range: 50-69 years old). The activity level and movement index on night 4 were significantly lower in bright light conditions, compared with the controlled condition. The activity level during the day was not significantly different between the two conditions. These results indicate that 8000 lux morning bright light improves sleep quality in healthy elderly women.