Influence of exercise on linear growth.

The effects of exercise on linear growth were investigated in malnourished rats and in preschool children recovering from protein-energy malnutrition (PEM). Physical activity was either restricted or forced upon weanling rats that were pair-fed with 73 or 49% of the food eaten ad libitum by rats of the same age. Physically active animals grew more in length and weight than their inactive counterparts. In a subsequent study, 20 children, 24-48 months old, under treatment for severe PEM, were assigned to either an Active group (stimulated, but not forced, to participate in games and activities that involved walking uphill, climbing a ramp, running, tumbling and climbing stairs) or a Control group (with the ad libitum pattern of physical activity and rest commonly observed in child-care and nutrition rehabilitation centers). Dietary intake was controlled and almost identical in both groups (2.5 +/- 0.07 g protein and 117 +/- 7 kcal/kg/day). Mean energy expenditure during daytime, assessed by heart rate monitoring and its relationship with oxygen consumption, were 2.0 and 1.7 times basal metabolic rate in the Active and Control groups, respectively (P < 0.01). In 6 weeks, both groups gained an average of 1.98 kg. However, the Active group grew more in length (22 +/- 8 vs 14 +/- 6 mm, P < 0.05) and lean body mass (final creatinine-height index: 0.97 +/- 0.12 vs 0.89 +/- 0.09, P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)