Department of Kinesiology, University of Illinois at Urbana/Champaign, 906 South Goodwin Avenue, Urbana, Illinois 61801, USA
Address for correspondence: Jeffrey A. Woods, Department of Kinesiology, University of Illinois at Urbana/Champaign, 906 South Goodwin Avenue, Urbana, IL 61801. Voice: 217-244-8815; fax: 217-244-7322.
woods1{at}uiuc.edu
Ann. N.Y. Acad. Sci. 959: 117-127 (2002).
Many strategies have been used to improve immune function in
the aged. Unfortunately, many of these interventions have been
disappointing, impractical, costly to develop and administer,
or accompanied by adverse side effects. Aside from dietary manipulation
(caloric restriction without malnutrition or antioxidant supplementation),
research involving behavioral preventative or restorative therapies
has been lacking. Moderate exercise training has been shown
to elicit beneficial outcomes in both the prevention and rehabilitation
of many diseases of the elderly. It has been hypothesized that
moderate levels of exercise improves, whereas strenuous exercise
or overtraining suppresses, various immune function measures.
Three general approaches have been implemented to study the
impact of exercise on immune functioning in the elderly: (1)
cross-sectional studies, (2) longitudinal studies, and (3) animal
studies. In general, cross-sectional studies examining highly
active elderly have demonstrated improved
in vitro T cell responses
to polyclonal stimulation when compared to sedentary elderly.
This is corroborated by several animal studies that have shown
improved splenic T cell responses
in vitro. Unfortunately, human
prospective studies have failed to demonstrate consistent improvements
in various measures of immune function in older adults. However,
it should be cautioned that these studies have included small
samples followed over a short duration, measuring a limited
number of
in vitro immune parameters, with some failing to account
for potential confounding influences. Although such findings
have the potential to be of substantial public health importance,
very few systematic studies have been conducted.
