RESUMEN
OBJECTIVE: To assess the effect of range-of-motion exercise program on bone mineralization and somatic growth of very low birth weight (VLBW) infants. STUDY DESIGN: A total of 36 VLBW infants were randomized into 18 VLBW infants receiving range-of-motion exercise and 18 VLBW control infants receiving tactile stimulation for 4 weeks. Laboratory investigations were performed at baseline and postexercise and included serum calcium, serum phosphorus (s.PO4), magnesium, alkaline phosphatase (ALP), urinary calcium/phosphate ratio, and serum carboxy-terminal cross-linked telopeptide of type 1 collagen (CTX). Dual-energy X-ray absorptiometry was performed at the end of the exercise protocol to measure bone mineral content, bone mineral density (BMD), bone area, lean mass, and fat mass. RESULTS: The weight and the rate of weight gain were significantly higher (p < 0.001) in the exercise group compared with controls postexercise. Also, higher s.PO4, lower ALP, and lower urinary calcium/phosphate ratio were observed postexercise in the exercise group (p = 0.001, p = 0.005, and p = 0.04, respectively), whereas serum CTX showed no difference between the two groups (p = 0.254). Postexercise BMD significantly improved in the exercise group (p < 0.001) compared with controls. CONCLUSION: Although the sample size was small, we may be able to suggest favorable effects of range-of-motion exercise versus tactile stimulation on bone metabolism, BMD, and short-term growth in VLBW infants.
