RESUMEN
PURPOSE: The purpose of this study was to investigate the oxidative stress response to a short duration bout of submaximal exercise in a cohort of healthy young adults. METHODS: 15 apparently healthy college age males and females completed a modified Bruce-protocol treadmill test to 75-80% of their heart rate reserve. Blood samples collected immediately before (pre-exercise), immediately after, 30, 60 and 120 minutes post-exercise were assayed for total antioxidant capacity (TAC), superoxide disumutase (SOD), thiobarbituric acid-reactive substances (TBARS), and protein carbonyls (PC). RESULTS: SOD activity was significantly increased from pre-exercise levels at 30 minutes (77%), 60 minutes (33%), and 120 minutes (37%) post-exercise. TAC levels were also significantly increased from pre-exercise levels at 60 minutes (30%) and 120 minutes (33%) post-exercise. There were no significant changes in biomarkers for reactive oxygen/nitrogen species (RONS) mediated damage (TBARS and PC) across all post-exercise time points. CONCLUSIONS: In a cohort of healthy young adults, a short duration bout of submaximal aerobic exercise elicited increases in antioxidant activity/concentration, but did not evoke changes in oxidative stress-induced damage. These results may suggest that: (1) short duration bouts of submaximal aerobic exercise are sufficient to induce RONS generation; and (2) the antioxidant defense system is capable of protecting against enhanced RONS production induced by a short duration, submaximal exercise bout in healthy young adults.
RESUMEN
Extracardiac chest ultrasonography was performed in 51 children for characterization and localization of pleural disease (29 children), for evaluation of chest and mediastinal masses (12), and for determining the cause of unilateral chest radiographic opacification (10). Ultrasonography clearly differentiated drainable fluid from pleural thickening, accurately characterized chest and mediastinal masses, guided aspiration and drainage procedures, and allowed rapid diagnosis of causes of unilateral opaque hemithorax.