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jtitle_s:("Age (dodr)")
1.  Oxidative stress in older adults: effects of physical fitness 
Age  2011;34(4):969-982.
Acute exercise results in transient change in redox balance. High concentrations of reactive oxygen species (ROS) can lead to oxidative damage to macromolecules. However, moderate periodic increases in ROS, such as experienced with habitual exercise, may activate signal transduction pathways which stimulate increases in endogenous antioxidant systems. This study tested the hypothesis that physically fit older adults would have less oxidative stress than unfit age-matched controls, due to greater circulating concentrations of non-enzymatic antioxidants and greater capacity to upregulate antioxidant enzymes. We compared 37 fit (mean age 65.2 ± 5 years) and 35 unfit (mean age 67.7 ± 4 years) men and women. Fitness status was classified by VO2 max and maximal leg power. Basal levels of oxidative stress were assessed by measuring urinary markers of nucleic acid damage and lipid peroxidation. Antioxidant status was assessed by measuring total antioxidant power and ratios of reduced to oxidized glutathione in plasma, at rest. The capacity to counteract an oxidative insult was assessed by measuring changes in plasma F2-isoprostanes in response to forearm ischemia–reperfusion. The fit individuals had significantly lower levels of urinary markers of oxidative damage (all P <0.05) and lower F2-isoprostane response to the oxidative challenge (P < 0.05), but there were no group differences in antioxidant status. The lower levels of oxidative stress in the fit individuals were not mediated by known effects of exercise training such as adiposity, HDL concentrations, or small molecular weight antioxidants. These data suggest that reduced oxidative stress associated with physical fitness results from differences in activity of antioxidant enzymes.
Electronic supplementary material
The online version of this article (doi:10.1007/s11357-011-9277-6) contains supplementary material, which is available to authorized users.
PMCID: PMC3682074  PMID: 21671197
F2-isoprostanes; Ischemia–reperfusion; Exercise; Glutathione; 8-Hydroxy-2′-deoxyguanosine
2.  Praising life and longevity—“In memoriam: Chris Heward” 
Age  2009;31(2):85-86.
PMCID: PMC2693734
3.  High-dose statin use does not impair aerobic capacity or skeletal muscle function in older adults 
Age  2008;30(4):283-291.
3-Hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors (statins) are lipid-lowering agents widely employed for atherosclerosis prevention. HMG-CoA reductase blockade reduces skeletal muscle coenzyme Q10 (CoQ10) levels and mitochondrial respiratory chain activities and may produce mild to severe skeletal muscle myopathy. This study investigated whether high-dose statin treatment would result in measurably decreased exercise capacity in older men and women. Maximal oxygen consumption, aerobic endurance, oxygen uptake kinetics, maximal strength, muscular power, and muscular endurance were measured before and after 12 weeks of statin treatment (simvastatin, 80 mg/day) in nine men and one woman, ages 55–76 years, with LDL-cholesterol levels >3.3 mmol/l (mean = 4.2 ± 0.2 mmol/l). Myalgia symptoms were assessed every 4 weeks. As expected, statin treatment resulted in significant decreases in LDL- and total-cholesterol levels (P < 0.01) with no significant changes in HDL-cholesterol or triglyceride levels. No significant changes were observed in aerobic capacity, endurance, oxygen kinetics or any measures of muscle function. No subject reported symptoms of myalgia, cramps, or weakness during the study. In the absence of myalgia or myopathic symptoms, high-dose simvastatin treatment did not impair exercise capacity in hyperlipidemic older individuals. We conclude that decreases in intramuscular CoQ10, in most patients on high dose statin treatment may not be clinically relevant, due to inter-individual variability in the degree of CoQ10 depletion, sensitivity of muscle to decreases in CoQ10, or both.
PMCID: PMC2585641  PMID: 19424852
Aging; Simvastatin; Vo2max; Strength; O2 uptake kinetics; Myalgia

Results 1-3 (3)