I Margaritis1, A S Rousseau, J F Marini, A Chopard. 1. Department for evaluation of nutritional and health risks, French Food Safety Agency, Maisons-Alfort, France. i.margaritis@afssa.fr
Abstract
OBJECTIVES: The aim of the study was to evidence oxidative damage and erythrocyte antioxidant enzyme activities during long term bed rest (LTBR) and recovery, while verifying the prophylactic effects of resistance exercise on LTBR-induced oxidative damage. DESIGN AND METHODS: 11 healthy male participated in the study. Nutrient intakes were monitored. Assessments occurred during LTBR (60th and 90th day) and 90 days after the end. RESULTS: LTBR induced only a slight decrease in total thiol protein (SH) group concentrations. Glutathione peroxidase (GPx) activity was upregulated during LTBR and down regulated after recovery suggesting that hypokinesia induces an oxidative stress. These effects where not correlated to antioxidant intake as nutritional density is preserved. Lipoperoxidative markers stay unchanged. CONCLUSIONS: Exercise alleviates hypokinesia outcomes by preserving glutathione reductase activity with minor effect on hypokinesia-induced antioxidant response and oxidative stress which both exhibit a high magnitude inter-individual variability. Return to initial physical activity allows biomarkers to return to initial values marking the end of the stress. Hypokinetic situations should be considered as an oxidative stressful situation requiring exercise and nutritional strategies.
OBJECTIVES: The aim of the study was to evidence oxidative damage and erythrocyte antioxidant enzyme activities during long term bed rest (LTBR) and recovery, while verifying the prophylactic effects of resistance exercise on LTBR-induced oxidative damage. DESIGN AND METHODS: 11 healthy male participated in the study. Nutrient intakes were monitored. Assessments occurred during LTBR (60th and 90th day) and 90 days after the end. RESULTS:LTBR induced only a slight decrease in total thiol protein (SH) group concentrations. Glutathione peroxidase (GPx) activity was upregulated during LTBR and down regulated after recovery suggesting that hypokinesia induces an oxidative stress. These effects where not correlated to antioxidant intake as nutritional density is preserved. Lipoperoxidative markers stay unchanged. CONCLUSIONS: Exercise alleviates hypokinesia outcomes by preserving glutathione reductase activity with minor effect on hypokinesia-induced antioxidant response and oxidative stress which both exhibit a high magnitude inter-individual variability. Return to initial physical activity allows biomarkers to return to initial values marking the end of the stress. Hypokinetic situations should be considered as an oxidative stressful situation requiring exercise and nutritional strategies.
Authors: Noortje van Duijnhoven; Evelyne Hesse; Thomas Janssen; Will Wodzig; Peter Scheffer; Maria Hopman Journal: Eur J Appl Physiol Date: 2010-04-03 Impact factor: 3.078