The Effects of Exercise on Depression Symptoms Using Levels of Neurotransmitters and EEG as Markers

There is an increasing demand for clinical effective, safe, and cost conscious forms of
treatment for depression. Research shows depression to account for the largest decrease in
overall health compared to asthma, angina, arthritis, and diabetes (Maussavi, 2007). The
cost of lost productivity at work due to depression is a new focus of research as no current
and accurate numbers exist. Stewart, Ricci, Hahn, & Morganstein (2013) were among the first
to examine this issue and found that lost productivity due to depression cost an estimated
$44 billion dollars per year in spite of current medical treatments commonly prescribed. The
lost productivity among those with depression and the low level of treatment suggest that
there may be cost effective opportunities for improving depression outcomes within the
general workforce and society at large.

The question of value regarding the use of exercise as a treatment for depression has
remained a source of investigation in recent years. In cooperation with Centra Health and
Liberty University, this study seeks to understand the mechanisms that make exercise a
viable treatment in depression by examining self-report of symptoms, serum levels of
serotonin and catecholamines (epinephrine, norepinephrin, and dopamine) and frontal slow
wave EEG activity as markers. Although these markers have been examined individually in
previous studies, this is the only known study that examines each of these components in a
single study. Such information can be useful in understanding the overall neurological
components of depression and the effects of exercise on the brain in depressed individuals
that would make the prescription of exercise a viable treatment in depression.

Multiple trials, meta-analyses, and reviews have been conducted in the attempt to clarify
the use of exercise in depressed patients. Research has shown that exercise as a treatment
may result in fewer relapses than sertraline (Strohle, 2009). Similar results are indicated
when exercise is prescribed as an adjunct treatment with psychotherapy (Balon, Sidhu, &
Pankhuree, 2009; Blumenthal, Smith, & Hoffman, 2012; Gill, Womack, & Safranek, 2010).
Preliminary characteristics of the ideal dosage of exercise as a treatment have been
researched, although a definitive dose-response curve has yet to be produced (Callaghan,
Khalil, Morres, & Carter, 2011; Perraton, Kumar, & Machotka, 2010).

Electroencephalographic (EEG) scans have been shown to demonstrate a left frontal bias in
alpha (8-12 Hz) and theta (4-7 Hz) wave activity (Allen, Urry, Hitt, & Coan, 2004; Demos,
2005; Iosifescu et al., 2008; Nissen et al., 2006). The up-training or down-training of
individual bandwidths in the treatment of depression, anxiety, ADHD, and traumatic brain
injury have long been established (La Vaque, 2002). Although there are no established norms
for neurotransmitter levels, we know through clinical medication trials that the inhibition
of the reuptake of serotonin and or norepinephrine improve mood. Previous studies examining
low levels of serotonin and decreased mood have found a correlation between exercise and
increased serotonin availability without the use of pharmaceuticals (Chaouloff et al., 1985;
Ernst, Olsen, Pinel, Lam, & Christie, 2006; Jacobs & Fornal, 1999). More routine type
studies often use neurotransmitter levels as markers (Lande, Williams, Fileta, 2012;
Lidberg, Tuck, Asberg, Scalia-Tomba, & Bertilsson, 1985; Mann & Stanley, 1984).

Inclusion Criteria:

- primary diagnosis of depression 18-65 years of age Physically fit to engage in
physical exercise

Exclusion Criteria:

- Participants with a history or current symptoms of psychosis anticipation of
psychiatric medication changes over the course of the study Bipolar disorder or other
disorder reflecting reality testing impairment.