An Examination of the Relationship Between Caloric Expenditure and Aerobic Capacity Among Sixth Grade Hispanic Students

Previous researchers have indicated a general consensus on the positive relationship between caloric expenditure and aerobic capacity among children. However, this finding has mainly been based on the general youth population that includes a majority of Caucasians. It is unknown about its applicability to different ethnic minorities, such as Hispanic children, whose participation in physical activities are often confined by their social, cultural, economical, and individual conditions. Although the Hispanic population is the fastest growing segment of American society, little scientific information is available pertaining to the fitness levels and caloric expenditure of children in this ethnic group. The purpose of this study was to examine the relationship between caloric expenditure and aerobic capacity (VO_2max) among sixth-grade Hispanic children. After obtaining permission from the Institutional Review Board for the Protection of Human Subjects and the parents/guardians to conduct the study, a total of 279 participants (158 males and 121 females) completed a modified 7-day recall caloric expenditure survey and performed an exercise session that consisted of the 20-m PACER shuttle test. Other measurements included age, gender, height, body weight, and sum of skinfolds. Physical characteristics of the male and female participants were (mean±sd): age(yrs)=10.9±0.6, 10.9±0.6; height(cm)=149.5±9.2, 150.5±7.7; weight(kg)=47.9±15.6, 49.0±12.6; body fat(%)=26.9±9.8, 27.4±7.0, sum of skinfolds(mm)=32.3±12.6, 35.7±9.8; VO_2max(ml/min)=1636.6±360.0, 1415.8±304.9; VO_2max(ml^.kg^.min^-1)=35.7±7.0, 29.4±3.8, respectively. Data from these measurements were utilized in a multiple regression model to calculate VO_2max (Suminski et al., 1999). Caloric expenditure was calculated from an established equation (Koo & Rohan, 1999). Caloric expenditure in the participants ranged from 231.9 - 1260.7 kcals/day with a mean expenditure of 450.3 kcals/day. Descriptive statistics for caloric expenditure and VO_2max were computed, which revealed that male and female Hispanic children had lower daily caloric expenditure and lower VO_2max when compared to Caucasians. Regression analysis revealed that caloric expenditure (kcals/day) was a significant (p<.05) predictor of aerobic capacity (R=.466, SEE=314 ml/min), suggesting that low VO_2max in Hispanic children is likely influenced by their low level of daily caloric expenditure. Procedures for enhancing physical activity levels of Hispanic children are the focus of the discussion.
Keyword(s): exercise/fitness, physical activity, student issues