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Updated: Aug 25, 2026
Assessment of Child Anthropometry in a Large Epidemiologic Study
Published on: February 2, 2017
Mechanical efficiency of normal-weight prepubertal boys predisposed to obesity
Yitzhak Weinstein1, Tamir Kamerman, Elliot Berry
1The Ribstein Center for Sport Medicine Sciences and Research, Wingate Institute, ISRAEL. itzw@macam.ac.il
Insights
Energy expenditure during rest and submaximal exercise, and mechanical efficiency, do not differ between normal-weight boys predisposed to obesity and those not predisposed. These factors may not predict future obesity in this group.
Area of Science:
- Pediatric Endocrinology
- Metabolic Research
- Obesity Studies
Background:
- Childhood obesity is a growing public health concern.
- Identifying early predictors of obesity is crucial for timely intervention.
- Genetic predisposition plays a significant role in obesity development.
Purpose of the Study:
- To compare resting and submaximal exercise energy expenditure between normal-weight boys with and without a parental history of obesity.
- To assess and compare the mechanical efficiency during exercise in these two groups of boys.
- To determine if energy expenditure or mechanical efficiency can predict obesity risk in prepubertal boys.
Main Methods:
- Two groups of 9-12-year-old boys were studied: one with normal-weight parents (NP) and another with at least one obese parent (OP).
- Anthropometric measurements, resting metabolic rate, submaximal exercise oxygen consumption (VO2), and mechanical efficiency were assessed.
- Physical activity habits were also recorded and compared between groups.
Main Results:
- No significant differences were observed in body mass, stature, or body fat percentage between the NP and OP groups.
- Resting metabolic rate and submaximal VO2 at various workloads were similar in both groups.
- Mechanical efficiency during exercise and peak oxygen consumption (VO2peak) did not differ between normal-weight boys predisposed to obesity and those without such predisposition.
Conclusions:
- Energy expenditure at rest and during submaximal exercise is not a distinguishing factor in normal-weight prepubertal boys with a parental predisposition to obesity.
- Mechanical efficiency during exercise does not appear to be an early predictor of obesity in this population.
- These findings suggest that metabolic and mechanical factors studied here may not be reliable indicators for predicting future obesity in at-risk, normal-weight children.
Purpose:
To compare 1) energy expenditure during rest and during submaximal exercise, and 2) the mechanical efficiency of normal-weight boys liable to obesity with normal-weight boys who are not liable to obesity.
Methods:
Two groups of prepubertal boys, aged 9-12 yr were compared, one with both parents of normal weight (NP, 20 < or = BMI < or = 27, N = 20) and the other (N = 20) with one obese parent (OP, BMI > or = 30).
Results:
No significant differences were found between the two groups in the anthropometric measurements (means +/- SD): body mass (32.9 +/- 5.4 and 31.5 +/- 3.1 kg, NP and OP, respectively), stature (141.0 +/- 6.2 and 140.0 +/- 5.5 cm, NP and OP, respectively), and body fat (16.6 +/- 3.5 and 15.1 +/- 3.5%, NP and OP, respectively). Likewise, there were no differences in the reported physical activity habits. No differences were observed in the resting metabolic rate values between the two groups (5.071 +/- 0.351 and 4.956 +/- 0.386 MJ x d(-1) , NP and OP, respectively). Submaximal VO2 at 30, 45, and 60 W was similar in the two groups (0.63 +/- 0.05, 0.78 +/- 0.06, and 0.92 +/- 0.08; and 0.63 +/- 0.06, 0.78 +/- 0.08, and 0.95 +/- 0.08 L x min(-1), NP and OP, respectively). Likewise, the mechanical efficiency, calculated at 30, 45, and 60 W was similar in both groups (19.5 +/- 2.3, 21.8 +/- 2.2, 23.4 +/- 2.5%; and 19.5 +/- 3.0, 21.9 +/- 2.9, 22.6 +/- 2.5%, NP and OP, respectively. No differences were found between groups in their VO2peak (38.4 +/- 3.8 and 40.4 +/- 4.9 mL x kg(-1) x min(-1), NP and OP, respectively).
Conclusion:
These data suggest that energy expenditure during rest and exercise may not be used to predict future obesity in normal-weight prepubertal boys predisposed to obesity.
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