April 2, 1997

Sleep Quality in Older Adults: Effects of Exercise Training and Influence of Sunlight Exposure-Reply

Author Affiliations

University of Washington Seattle

JAMA. 1997;277(13):1035. doi:10.1001/jama.1997.03540370025019

In Reply.  —I agree with the comments of Drs O'Connor and Youngstedt to the extent that, as I noted in my Editorial, the physiological mechanisms for exercise-related improvements in sleep quality are unclear. The data presented in the article by King et al1 do not rule out the possibility that sunlight exposure during exercise may be involved in exercise-related improvements in sleep. In the Editorial, I called for additional research to address issues such as this.However, I am not convinced by the evidence presented by O'Connor and Youngstedt that sunlight exposure can account for the observed improvements in sleep. Notably, they do not cite a single study that reports sleep quality in older community-living adults can be improved in older adults simply by spending more time outside during daylight hours. Also, they do not adequately discuss the issue of the dose of sunlight. Note that, of the 4 days per