ABSTRACT
BACKGROUND: The 20-metre multistage shuttle run test is a useful method for the regular monitoring of aerobic fitness. However, the validity of the test should be established in the particular population prior to application. The aim of the study was to validate the applicability of the 20-metre multistage shuttle run test in non-athlete, girls from Kolkata, India. METHODS: Thirty-six untrained girls from different schools in Kolkata (age range 14-16 years) were recruited for the study. Direct estimation of cardiorespiratory endurance (VO(2)max) comprised treadmill exercise followed by expired gas analysis using Scholander micro-gas analyser. VO(2)max was indirectly predicted by the 20-metre multistage shuttle run test. RESULTS: The difference between the mean (SD) VO(2)max values of the direct measurement, 32.91 (2.66) ml·kg(-1)·min(-1), and the 20-metre multistage shuttle run test, 33.79 (2.56) ml·kg(-1)·min(-1), was statistically significant (P < 0.01). However, limits of agreement analysis suggested that the 20-metre multistage shuttle run test can be applied for use with the studied population. Intra-class correlation coefficients also suggested good reliability of the 20-metre multistage shuttle run data. CONCLUSION: The results suggest that the use of the 20-metre multistage shuttle run test for the prediction of VO(2)max is justified in the studied population. For better prediction of VO(2)max, a new equation has been developed based on the present data for untrained girls from Kolkata.
ABSTRACT
PURPOSE: Validity of the 20-meter multi stage shuttle run test (20-m MST) has not been studied in Nepalese population. The purpose of this study was to validate the applicability of the 20-m MST in Nepalese adult females. METHODS: Forty female college students (age range, 20.42 ~24.75 years) from different colleges of Nepal were recruited for the study. Direct estimation of VO(2) max comprised treadmill exercise followed by expired gas analysis by scholander micro-gas analyzer whereas VO(2) max was indirectly predicted by the 20-m MST. RESULTS: The difference between the mean (±SD) VO(2) max values of direct measurement (VO(2) max = 32.78 +/-2.88 ml/kg/min) and the 20-m MST (SPVO(2) max = 32.53 + /-3.36 ml/kg/min) was statistically insignificant (P>0.1). Highly significant correlation (r=0.94, P<0.01) existed between the maximal speed of the 20-m MST and VO(2) max. Limits of agreement analysis also suggest that the 20-m MST can be applied for the studied population. CONCLUSION: The results of limits of agreement analysis suggest that the application of the present form of the 20-m MST may be justified in the studied population. However, for better prediction of VO(2) max, a new equation has been computed based on the present data to be used for female college students of Nepal.
ABSTRACT
Generation of reactive oxygen species (ROS) is a normal process in the life of aerobic organisms. Under physiological conditions, these deleterious species are mostly removed by the cellular antioxidant systems, which include antioxidant vitamins, protein and non-protein thiols, and antioxidant enzymes. Since the antioxidant reserve capacity in most tissues is rather marginal, strenuous physical exercise characterized by a remarkable increase in oxygen consumption with concomitant production of ROS presents a challenge to the antioxidant systems. An acute bout of exercise at sufficient intensity has been shown to stimulate activities of antioxidant enzymes. This could be considered as a defensive mechanism of the cell under oxidative stress. However, prolonged heavy exercise may cause a transient reduction of tissue vitamin E content and a change of glutathione redox status in various body tissues. Deficiency of antioxidant nutrients appears to hamper antioxidant systems and augment exercise-induced oxidative stress and tissue damage. Chronic exercise training seems to induce activities of antioxidant enzymes and perhaps stimulate GSH levels in body fluids. Recent research suggest that supplementation of certain antioxidant nutrients are necessary for physically active individuals.
