A single 30-minute walk on a treadmill can
give a temporary emotional lift to patients diagnosed
with major depressive disorder, the results of a small
study suggest.
Researchers found that among 40 men and women recently
diagnosed with major depression, those who spent just
a half hour on a treadmill reported a short-term improvement
in energy and emotional well-being.
Though a single workout is not the answer to clinical
depression, the researchers say, exercise could offer
depressed patients a way to give themselves an emotional
boost.
"If you can go out and walk and get the recommended amount
of exercise, then it might help you manage your symptoms
on a day-to-day basis," said lead study author Dr. John
Bartholomew of the University of Texas at Austin.
Past studies, he explained in an interview, have shown
that regular exercise can help treat depression over time.
But the new findings show that "you don't have to wait"
to start getting some benefit, he said.
Bartholomew and his colleagues report their findings
in the journal Medicine & Science in Sports & Exercise.
A number of studies have found that active adults are
less likely to suffer depression than their sedentary
peers, while some clinical trials have shown regular exercise
can serve as a therapy for the disorder -- and perhaps
be as effective as antidepressant drugs in some cases.
But the immediate effects of exercise on depressed individuals
have been unclear.
Patients in the current study were randomly assigned
to walk on a treadmill for 30 minutes or spend the time
resting quietly in a comfortable chair. All completed
standard surveys of mood and well-being before and after
their exercise or rest period.
The researchers found that both exercise and quiet rest
appeared to boost patients' mood, helping them feel less
fatigue, tension, distress and anger.
But the exercisers reported greater gains in general
well-being and "vigor," the study found.
According to Bartholomew, the quiet-rest group may have
felt better just because they were getting out of the
house and interacting with others. People with depression,
he noted, often isolate themselves and avoid social situations,
which can in turn feed the depression.
Experts have speculated that exercise aids depression,
in part, through direct physiological effects. For example,
physical activity seems to affect some key nervous system
chemicals -- norepinephrine and serotonin -- that are
targets of antidepressant drugs, as well as brain neurotrophins,
which help protect nerve cells from injury and transmit
nerve signals in brain regions related to mood.
But Bartholomew said there may be "cognitive" effects
at work. Exercisers in this study, he explained, may have
felt a "sense of accomplishment" that lifted their general
mood.
One of the challenges to using exercise as depression
therapy is that the condition makes it hard for people
to find the motivation to be active, Bartholomew noted.
But if they can get outside for even a short walk, he
said, it could help in managing the daily symptoms of
the disorder.
SOURCE: Medicine & Science in Sports & Exercise, December
2005.
