AGING, ANTIOXIDANT STATUS, EXERCISE, OXIDATIVE STRESS

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AGING, ANTIOXIDANT STATUS, EXERCISE, OXIDATIVE STRESS - Physical

Activity, Carotenoids, Beta-Carotene, Athletes

Reference: " Physical activity alters antioxidant status in exercising

elderly subjects, " Rousseau AS, Margaritis I, et al, J Nutr Biochem,

2006; 17(7): 463-70. (Address: Laboratoire Physiologie des Adaptations,

Performances Motrices et Sante, EA 3837, Universite de

Nice-Sophia-Antipolis, 06205 Nice Cedex 3, France. E-mail:

asrousse@... ).

Summary: In a study involving exercising and sedentary elderly and

young male subjects, elderly exercising subjects were found to have

lower plasma concentrations of certain antioxidants, particularly

carotenoids, suggesting that the adaptive mechanism that appears to be

present in young exercising subjects, in whom aerobic exercise training

may reinforce the endogenous antioxidant defense system, is not

efficient in the same manner in elderly exercising subjects. The study

involved 18 healthy exercising elderly (EE) subjects (68.1 y), 7

sedentary elderly (SE) subjects (70.4 y), 17 exercising young (EY)

subjects (31 y) and 8 sedentary young (SY) subjects (27 y). Exercising

subjects were considered those who participated in at least one hour of

aerobic physical activity three times per week. Intake of antioxidants

and activity level were assessed via 7-day food and activity records

kept by subjects. Exercising elderly subjects were found to have lower

carbohydrate and protein intak es with respect to their body weight, as

compared to exercising young subjects. Both elderly and young exercising

subjects had higher intakes of total energy, fiber and fruit, as

compared to their sedentary counterparts. Intakes of vitamins C and E

and beta-carotene were higher among exercising elderly subjects, as

compared to exercising young subjects. Analysis of blood samples taken

on day 8 revealed exercising elderly subjects to have higher erythrocyte

glutathione peroxidase (GSH-Px) activity, as compared to sedentary

elderly subjects and exercising young subjects, and higher levels of

blood oxidized glutathione and lower levels of plasma total thiol as

compared to exercising young subjects. Despite having higher intakes of

beta-carotene and other antioxidants (vitamins C and E), exercising

elderly subjects were found to have the lowest plasma concentrations of

carotenoids, specifically beta-carotene. These results suggest that

elderly subjects who are exercising re! gularly may have specific

antioxidant requirements. Additional research is needed to determine the

effects of specific antioxidant supplementation in such a population.

--

ne Holden, MS, RD < fivestar@... >

" Ask the Parkinson Dietitian " http://www.parkinson.org/

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