Background. So-called atypical depressive symptoms (carbohydrate
craving, prolonged sleep,
weight gain, increased appetite) frequently emerge in association with
low illumination to which
people are ordinarily exposed indoors, or even outdoors at extreme latitudes
in wintertime. Our
objective was to analyse the effect of physical exercise alone or combined
with bright light on mood
and the health-related quality of life during winter.
Methods. We carried out a randomized controlled trial on 120
indoor employees in southern
Finland between November and January. The subjects were allocated to supervised
under bright (2500–4000 lx) or ordinary (400–600 lx) light
conditions in a gym 2–3 times weekly for
8 weeks, or supervised relaxation training once a week over the same period
as active placebo. We
collected questionnaire data on the changes in mood and health-related
quality of life after 4 and
8 weeks of training, and after 4 months follow-up.
Results. Fitness training in bright light resulted in greater
relief from atypical depressive symptoms
and more vitality than in ordinary room light. Compared with relaxation
alone, the former regime
improved general mental health and social functioning in addition to the
improvement in depressive
symptoms and vitality, whereas the latter only increased vitality.
Conclusions. Supervised physical exercise combined with exposure
to bright light appears to be an
effective intervention for improving mood and certain aspects of the health-related
quality of life in
wintertime. This effect appears unrelated to the history of season-dependent
noticeable among healthy individuals.