Association of Cardio respiratory Fitness, Body Composition and Blood Pressure in Collegiate Population of Amritsar, Punjab, India
blood pressure, fat mass, vo max
S Koley. Association of Cardio respiratory Fitness, Body Composition and Blood Pressure in Collegiate Population of Amritsar, Punjab, India. The Internet Journal of Biological Anthropology. 2006 Volume 1 Number 1.
Maximal oxygen consumption (VO2 max) is single best measure of cardiorespiratory capacity and is considered as a benchmark to quantify cardiovascular functional capacity and aerobic fitness. The present study deals with the association of cardio respiratory fitness, body composition and blood pressure in collegiate population (n =180) of Amritsar, Punjab, India, aged 19 – 26 years. Height and weight were determined by anthropometric methods, blood pressure was measured with subjects lying supine after at least 5 min rest, VO2 max was measured by Queen's College Step test; fat mass and fat free mass were estimated by bioelectrical impedance analysis method. The results indicated that there was a close association of VO2 max with fat mass and systolic blood pressure in boys, and only with systolic blood pressure in girls.
Civilization and industrialization make our life pleasant, jubilant and luxuriant. Indeed, automation and other technologies have contributed greatly to lessening physical activities at work place and home. The assessment of cardio respiratory fitness in children and adolescent has been growing in importance because several data link the VO2 max with CVD risk factors1,2. Aerobic fitness is a very good indicator of cardio respiratory fitness / cardiovascular and exercise tolerance for every day activities which are largely aerobic for the general population3. Research has indicated the importance of exercise in reducing the risk of cardiovascular diseases, through reduction of blood lipids, body fat, and blood pressure, improvement in myocardial function and as an independent risk factor4. Thus, the concept of fitness being defined as good condition or good health, tells us that, while we do not expect the general population to compete with athletes, an above average VO2 max score indicates a healthy level of cardio respiratory fitness and that an individual is fit to cope with the general demands of living3. The evidence from longitudinal studies indicate that early identification of cardio vascular risk factors in children, particularly for body fat %, blood lipids, hypertension and cardio respiratory fitness should be addressed as preventive measure in public health perspectives5 . So these approaches may also be helpful in the studies relating to the young adults.
The studies on relationship among cardio respiratory fitness, body composition and blood pressure in school children are scanty6. So, the purpose of the present study was to fulfill the lacuna of knowledge in these aspects in young adults especially in north Indian context. Therefore, the aim of the present study was to study the association of cardio respiratory fitness with body composition and blood pressure in collegiate population of Amritsar, Punjab, India.
Materials And Methods
The sample consisted of 180 randomly selected unrelated normal healthy collegiate boys (n=110) and girls (n= 70) aged 19-26 years, taken from Guru Nanak Dev University, Amritsar, Punjab, India. The mean height and weight of boys and girls were 172.38 cm and 65.87 kg, and 157.92 cm and 53.16 kg, respectively. The consent for voluntary participation was obtained. The work was done in the department of Sports Medicine and Physiotherapy, Guru Nanak Dev University, Amritsar, Punjab, India.
Following equations were used for the estimation of Vo2max (mL.kg-1min-1)
Males: VO2max = 111.33 – [0.42 x Step-test pulse rate (b.min-1)]
Females: VO2max = 65.81 – [0.1847 x Step-test pulse rate (b.min-1)]
Results And Discussion
The distribution of mean values of 8 variables in collegiate population of Amritsar is shown in Table1. The boys have higher mean values in height (172.38 cm) , weight (65.87 kg) , body mass index (22.16 kg/m2), fat free mass (58.99 kg), VO2 max (48.74 ml. kg-1 min.-1), systolic blood pressure (122.27 mmHg) and diastolic blood pressure (77.51 mmHg) and lesser mean value in fat-mass (6.87 kg) than the girls (157.92 cm, 53.16 kg, 21.30 kg/m2, 43.97 kg, 33.97 ml. kg-1 min.-1, 116.69 mmHg, 73.51 mmHg and 9.13 kg respectively). Highly significant differences (p≤0.001) were noted in height (t=15.73), weight (t=8.02), fat-mass (t=3.93), fat-free-mass (t=13.47), VO2max (t=12.26), systolic blood pressure (t=4.82) and diastolic blood pressure (t=3.77) between boys and girls. The findings of the present study were supported by earlier reports 6,7,9,10,11.
The linear regression analysis between VO2 max and other 7 variables in boys and girls is shown in Table 2. The VO2 max has negatively significant correlations (p≤0.05) with fat mass (r= - 0.27) in only boys and with systolic blood pressure both in boys (r= - 0.23) and girls (r= - 0.31). Here, the linear regression analysis showed that, fat mass has strong correlation with VO2 max in boys. The lesser the fat mass in boys, greater is the VO2 max. The earlier study6 also showed that boys had greater VO2 max in comparison to girls. This may also be attributed, impart, to boys higher level of hemoglobin concentration and lower level of subcutaneous fat12.
The systolic blood pressure had a close negative correlation with VO2 max. The boys with lower systolic blood pressure had higher VO2 max values. This may be due to the fact that there exists certain cardiovascular adaptations with fitness training which cause lower blood pressure. The stroke volume increases with lower heart rate, there by increased capillarization of muscles and greater extraction of oxygen from the arteries9. These results also coincide with our findings.
The linear regression analysis for VO2 max and various parameters (except systolic blood pressure) did not find any correlation in the girls, may be because of the girls selected for the study were purely sedentary without any involvement in physical activity. The results do not match with the earlier report6 who found correlation between fat%, fat mass and Vo2max. Only the systolic blood pressure among girls had a correlation with VO2 max, may be the girls were relaxed and stable. Although there appears to be a genetic component in physical fitness13, several studies have documented relationship between fitness and cardiovascular disease risk factors in adults and children12,14.
The linear regression analysis between fat mass and other 6 variables in boys and girls is given in Table 3. The fat mass has positively significant correlations (p≤0.05) both in boys and girls with weight (r=0.81and 0.88 respectively), body mass index (r=0.86 and 0.87 respectively), and fat free mass (r=0.61 and 0.69 respectively).
The systolic blood pressure and diastolic blood pressure did not show any correlation with fat mass in both boys and girls. This is in contrary to the results of the earlier study11 which showed evidence of sex differences in relationship between measures of adiposity and blood pressure.
Table 4 gives the linear regression analysis between fat free mass and other 5 variables in boys and girls. Both in boys and girls, the fat free mass has positively significant correlations (p≤0.05) with height (r=0.47in both cases), weight (r=0.96 and 0.94 respectively) and body mass index (r=0.80 and 0.78 respectively). Lohman15 also stated that the density of fat free mass was greater in adult males in comparison with females and children. The coefficient of regression was also having a higher value for fat percent in the girls.
The linear regression analysis between systolic blood pressure and 4 other variables in boys and girls is shown in Table 5. The systolic blood pressure has positively significant correlations (p≤0.05) with diastolic blood pressure in boys (r=0.30) and in girls (r=0.54) respectively. The variation in systolic blood pressure and diastolic blood pressure may be due to interference of other variables like genetics16, socio-economic status17
Table 6 shows the linear regression analysis between diastolic blood pressure and other 3 variables in boys and girls where no significant correlations differences were noted in any case either in the boys or in the girls. Reddy et al20 have found that body mass index and triceps skin fold thickness were positively correlated with systolic blood pressure and diastolic blood pressure. Balogun et al21 have revealed that strong determinants of blood pressure levels were body mass, body mass index and triceps skin fold thickness but our results did not confirm this.
Thus from above discussion, it may be concluded that a correlation exists for various variables between cardio respiratory fitness, body composition and blood pressure. In order to have higher fitness profile and to avoid cardiovascular complications, young adults should take care of their food habits and physical activity to maintain a fat free body composition.