Antioxidant and oxidative stress responses of sojourners at high altitude in different climatic temperatures.

High altitude (HA) is a multi-stressor environment comprising hypobaric hypoxia and cold. Climatic temperature varies with seasonal variation at HA. The present study was undertaken to investigate the effect of ambient temperature on antioxidant profile among sojourners at HA. The study was conducted on sojourners exposed to an altitude of 4,560 m in two different seasons and categorized into two groups (SOJ 1, n=63, ambient temp. at HA: -6 degree to +10degreeC; SOJ 2, n=81, ambient temp. at HA: 3degree-22degreeC). Blood was collected at sea level (SL) and after 4 weeks of HA exposure. Antioxidant enzymes showed significant upregulation in SOJ 2 at HA. In SOJ 1, superoxide dismutase and glutathione peroxidase showed significant upregulation but catalase and glutathione reductase showed significant decrease at HA. Non-enzymatic antioxidants showed significant reduction in SOJ 1 whereas a sustained antioxidant profile was observed in SOJ 2 at HA. Oxidative stress markers showed higher levels in SOJ 1 than SOJ 2 at HA. Differences observed between SOJ 1 and SOJ 2 at HA may be the consequence of different environmental temperatures. Cold stress was higher in SOJ 1 as evidenced from the significantly lower oral temperature in SOJ 1 as compared to SOJ 2. Cold- and hypoxia-induced increase in energy expenditure was significantly high in SOJ 1 than SOJ 2. To conclude, chronic exposure to hypoxia in moderate climatic temperature has a potential preconditioning effect on antioxidant system, but exposure to both cold and hypoxia causes greater oxidative stress due to altered metabolic rate.

Comparison of pulmonary function amongst Ladakhi, Delhi, Vanvasi and Siddi female athletes.

Lung functions were studied in contemporary healthy Indian female athletes of Ladakhi, Delhi, Vanvasi and Siddi origin training for running events of varying distances. The aim of the study was to compare the lung function in females belonging to these four groups to examine lung function in relation to ethnic and environmental factors. Vital Capacity (VC), Forced Vital Capacity (FVC), Forced Expiratory Volume in Ist second (FEV1), Expiratory Reserve Volume (ERV), and Inspiratory Capacity (IC) were recorded using conventional closed circuit spirometry. Maximum Voluntary Ventilation (MVV) was estimated by collecting expired air during deep and rapid breathing in a 100 liters meterological balloon for a period of 15 seconds and measuring its volume. It was found that Ladakhi females were having significantly higher VC, FVC and FEV1 values than their counterparts. However, there was no significant difference in MVV amongst Delhi, Siddi and Vanvasi young females. The average MVV of Ladakhi females was only significantly higher than Siddi females (P < 0.05).

Comparison of pulmonary function amongst Ladakhi, Delhi, Vanvasi and Siddi boy athletes.

Lung functions were studied in contemporary healthy boy athletes of Ladakhi, Delhi, Vanvasi and Siddi origin. As lung function are related to ethnic and environmental factors, the aim of the study was to compare the lung function in boys belonging to these four groups. Vital Capacity (VC), Forced Vital Capacity (FVC), Forced Expiratory Volume in 1st second (FEV1), Expiratory Reserve Volume (ERV) and Inspiratory Capacity (IC) were recorded using conventional closed circuit spirometry. Maximum Voluntary Ventilation (MVV) was estimated collecting expired air during deep and rapid breathing in a 100 litres meterological balloon for a period of 15 seconds and measuring its volume. It was found that Ladakhi boys were having significantly higher VC, FVC and FEV1 values than their counterparts. However, there was no significant difference in MVV amongst Ladakhi, Delhi, Vanvasi and Siddi boys. Our results suggest that size of the lung is governed by genetic, environmental and nutritional factors and confirm that physical training during growth may help in developing a greater endurance in respiratory muscles.

Changes in lung function during adolescence in athletes and non-athletes.

The purpose of this study was to evaluate the lung function in Indian athletes and non-athletes during adolescence. For this, lung functions in 40 boys (twenty athletes and twenty non-athletes) in the age range of 13 to 16 years, were evaluated over a period of two years at yearly intervals. The variables studied were Forced Vital Capacity (FVC), Forced Expiratory Volume in one second (FEV1), Expiratory Reserve Volume (ERV), Inspiratory Capacity (IC) and Maximum Voluntary Ventilation (MVV). Our results suggest that the development of the lung during adolescence under proper nutritional and health conditions is governed by the process of growth with no or negligible additional effects of physical activity. It is summarized that physical activity during growth may increase endurance in respiratory muscles. However, the findings of this study does not reject the possibility that lung size may increase by a strenuous and prolonged strength training regimen during adolescence.

Lung function in middle distance adolescent runners.

Lung functions (FVC, FEV1, ERV, IC AND MVV) were evaluated in 14 boys and 11 girls practising for middle distance running events in the age range of 13 to 17 years before and after one year training. The findings suggest that during adolescence, development of lung under proper nutritional and health conditions is governed by the process of growth with negligible additional effect of physical activity. However, physical exercises during growth may help in developing a reduced resistance to expiration and a greater endurance in respiratory muscles.

Age and height as predictors of peak expiratory flow rate in Indian girls.

Peak expiratory flow rate (PEF) was measured on 175 healthy Indian girls in the age range 8-18 years with the help of Wright's Peak Flow Meter. PEF was recorded in the post absorptive phase at least 1 h after breakfast. The subjects rested for 0.5 h before the test procedure and tests were carried out between 1000-11000 hrs to avoid diurnal changes. The highest of three recordings was noted as the subject's PEF. PEF, age, height and body weight were correlated with each other and an intercorrelation matrix between these variables has been designed. It was observed, after performing multivariate regression analysis, that age and height are significant predictors of PEF. A multiple linear regression equation and a nomogram have been constructed for predicting PEF from age and height in young healthy Indian girls.

Pulmonary functions in ulcerative colitis.

The lung functions were evaluated in eighteen patients of ulcerative colitis, in a controlled study. There was statistically significant (p less than 0.01) reduction in maximum voluntary ventilation (MVV). Diffusing capacity (DLCo) was also reduced. Though the reduction in DLCo was not statistically significant, the importance of this finding as compared to the controls has been discussed. The findings are suggestive of subclinical restrictive ventilatory abnormality.

Effect of incentive breathing on lung functions in chronic obstructive pulmonary disease (COPD).

The effect of incentive breathing exercise was evaluated on patients of blue-bloater variety of chronic obstructive pulmonary disease (COPD) in a controlled study. The study used a device working on the principles of biofeed back for imparting breathing exercise. Exercise was given for half an hour daily for six weeks. There was significant increase in the vital capacity (VC) and reduction in air trapping in exercise group. There was remarkable improvement in subjective feeling of well being and breathlessness.