Effects Of Passive Physical Activity On Growth And Bone Development In Premature Infants

Background The goals for growth of preterm infants are to achieve a growth rate and a composition of weight gain similar to those of a normal fetus. Guaranteeing optimal growth for premature infants is the key for their development and decreasing disease risk.Bone development is strongly influenced by forces that are exerted upon the bones. Lack of mechanical stimulation in preterm infants places them at increased risk of osteopenia. In order to improve these problems because of prematurity, the early interventions of prompting the development for these premature infants are being researched.Objective To evaluate the effectiveness of early physical activity on the growth of premature infants hospitalized in the Neonatal Intensive Care Unit.Methods This research is a quasi-experimental study.30 premature infants were assigned to the control group from July,2014 to March,2015.30 premature infants were assigned to the intervention group from March,2015 to February,2016.The premature infants in the control group received the standard care of premature infants. In the intervention group, exercise protocol started on the day when provided with the energy of more than 110kcal/(kg·d), which involved daily extension and flexion range of motion against passive resistance of the upper and lower extremities (5 minutes per day,5 days per week,4 weeks) developed by Laurie J. Moyer-Mileur.Growth parameters,bone strength determined by using quantitative ultrasound measurement of bone speed of sound (SOS) at the middle right tibial shaft, all of which were measured at enrollment and after 4 weeks.Results (1)The growth rate of weight increased significantly in the intervention group with the number of 17.9 (16.4,21.2) g/(kg·d), while that of the control group was 16.6 (14.7,18.3) g/(kg·d) (P<0.05). Using generalized linear mixed models to evaluate the differences between groups and within groups in the growth rate of weight. Between groups, there are differences in the 3rd and 4th week(P<0.05).Whithin groups:there is a difference between the 1st and 4th week(P<0.008). (2)The mean energy intake in the intervention group is 123.0(119.9,126.1)kcal/(kg·d), while that of the control group is 119.4(117.8,123.0)kcal/(kg·d), there is a significant difference between the two groups (P< 0.01).(3)The bone SOS decreased significantly in the control group [-143.5(-190.8,-95.3)] m/s, whereas the bone SOS of the intervention group increased [72.0(-11.0,210.0)] m/s(P<0.01).Conclusions Early physical activity attenuates the decrease in bone strength and increases the growth rate of weight.