Effect of BMI, Body Fat Percentage and Fat Free Mass on Maximal Oxygen Consumption in Healthy Young Adults

J Clin Diagn Res. 2017 Jun;11(6):CC17-CC20. doi: 10.7860/JCDR/2017/25465.10039. Epub 2017 Jun 1.


Introduction: Maximal oxygen consumption (VO2max) is an important measure of cardiorespiratory capacity of an individual at a given degree of fitness and oxygen availability. Risk of cardiovascular diseases increases with increasing degree of obesity and a low level of VO2max has been established as an independent risk factor for cardiovascular mortality.

Aim: To determine VO2max in young adults and to find its correlation with Body Mass Index (BMI), Body Fat% and Fat Free Mass (FFM).

Materials and methods: Fifty four (male=30, female=24) healthy young adults of age group18-25 years after screening by Physical Activity Readiness Questionnaire (PAR-Q) participated in the study. Height was measured by stadiometer. Weight was measured by digital weighing scale with 0.1 kg sensitivity. Body fat% was measured by Bioelectrical Impedance Analysis (BIA) method. FFM was calculated by subtracting fat mass from the body weight. VO2max (mL.kg-1.min-1) was obtained by Submaximal Exercise Test (SET) by first two stages of Bruce Protocol with the basis of linear relationship between Heart Rate (HR) and oxygen consumption (VO2). Data were analysed statistically in GraphPad Prism software version 6.01 for windows.

Results: VO2max (mL.kg-1.min-1) of male (43.25±7.25) was significantly (p<0.001) higher than female (31.65±2.10). BMI showed weak negative correlation (r= -0.3232, p=0.0171) with VO2max but Body Fat% showed strong negative correlation (r= -0.7505, p<0.001) with VO2max. FFM positively correlated (r=0.3727, p=0.0055) with VO2max.

Conclusion: Increased body fat is associated with decreased level of VO2max in young adults. Obesity in terms of Fat% is a better parameter than BMI for prediction of low VO2max.

Keywords: Aerobic capacity; Bruce protocol; Cardiorespiratory fitness; Obesity indices; Submaximal exercise test.