Some evidence suggests that physical activity programs might promote short-term weight gain and bone mineralization in preterm infants .
Current evidence does not support the routine use of physical activity programs in preterm infants .
BACKGROUND Lack of physical stimulation may contribute to metabolic bone disease of preterm infants , result ing in poor bone mineralization and growth .
Physical activity programs combined with adequate nutrition might help to promote bone mineralization and growth .
OBJECTIVES The primary objective was to assess whether physical activity programs in preterm infants  improve bone mineralization and growth and reduce the risk of fracture .
Subgroup analysis : • Given that the smallest infants are most vulnerable for developing osteopenia ( Bishop 1999 ) , a subgroup analysis was planned for infants with birth weight < 1000 g.•  Calcium and phosphorus intake may affect an infant 's ability to increase bone mineral content ( Kuschel 2004 ) .
Sequential bone mineral content in small preterm infants with and without fractures and rickets.
Seventy-four infants with birth weights 1009 + /- 28 grams and gestational age 28.6 + /- 0.3 weeks ( M + /- SEM ) were studied prospect ively to test the hypotheses that bone mineral content ( BMC ) measured by photon absorptiometry , would be : ( 1 ) lower in very low birth weight ( VLBW ) infants with radiographic evidence of fractures and /or rickets ( F/R ) , and ( 2 ) will continue to be lower over the first year when compared to VLBW infants without F/R. BMC and bone width ( BW ) of the distal one-third of left radius and ulna were measured at 5 weeks ( n = 8) , 14 weeks ( n = 61 ) , 26 weeks ( n = 58 ) , 40 weeks ( n = 59 ) , and 1 year ( n = 52 ) .  St and ardized radiographs of both forearms , and weight , length , and head circumference were also determined at each study age . Investigators and technicians involved in the photon absorptiometry measurements were unaware of the radiographic findings and vice versa . Twenty-three of 74 infants were found to have F/R. BMC of studied infants remained markedly below our previously determined range of " intrauterine bone mineralization , " even at 26 weeks after birth . There was no significant difference in BMC or BW between infants with and without F/R , either at the time of confirmation of F/R or during early follow-up ; however , BMC was lower at greater than or equal to 6 months and BW was lower at greater than or equal to 9 months in infants with F/R. We suggest that the extremely low BMC measurements in early infancy predispose all VLBW infants to fractures and rickets
Some evidence suggests that physical activity programs might promote short-term weight gain and bone mineralization in preterm infants .
Current evidence does not support the routine use of physical activity programs in preterm infants .
BACKGROUND Lack of physical stimulation may contribute to metabolic bone disease of preterm infants , result ing in poor bone mineralization and growth .
Physical activity programs combined with adequate nutrition might help to promote bone mineralization and growth .
OBJECTIVES The primary objective was to assess whether physical activity programs in preterm infants  improve bone mineralization and growth and reduce the risk of fracture .
Subgroup analysis : • Given that the smallest infants are most vulnerable for developing osteopenia ( Bishop 1999 ) , a subgroup analysis was planned for infants with birth weight < 1000 g.•  Calcium and phosphorus intake may affect an infant 's ability to increase bone mineral content ( Kuschel 2004 ) .