Effects of Self-Regulated Physical Activity in Premature Infants on Bone Density and Length of Stay: A Pilot Study

Abstract

Importance: Premature infants are not prepared developmentally, physically, or cognitively with the multiple survival skills of the typical newborn. Objective: To determine whether physical activity generated spontaneously by premature infants stretching against the resistance of “prepod” garments is as effective as exercises provided by therapists in slowing bone density loss. Design: Preterm very low birth weight infants were placed in two nonrandomized parallel groups according to birth age. Setting: Infants routinely started in a traditional intense intervention setting and graduated to a special care section with private rooms that allowed parents to remain with their child. Participants: Healthy infants without medical complications, born between 28 and 32 wk postmenstrual age. Intervention: The control group received traditional exercises. The experimental group wore a prepod almost 24 hr a day. Outcomes and Measures: An ultrasound of the tibia was obtained at 31 to 32 wk and 4 wk later. Weight gain, head circumference growth, and length of stay (LOS) were also measured. Results: Although not statistically significant, the ultrasound results showed that the prepod group had less loss of bone density than the traditional therapy exercise group. The desired outcome was for pods to be as effective at reducing bone loss as traditional exercise, so the results exceeded expectations. The unexpected, and more notable, finding was a striking drop in LOS for the prepod group. Conclusions and Relevance: Spontaneous exercise by premature infants decreases bone loss and LOS. Better bone health and increased developmental maturity increase the chances of a positive developmental outcome and save the hospital significant expense. What This Article Adds: The prepod is a simple, cost-effective, noninvasive treatment tool occupational therapy practitioners can use to support a premature infant’s development. This study has considerable potential to affect how infants are served, both developmentally and financially.