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 ) .
Randomised controlled trial of effect of high-impact exercise on selected risk factors for osteoporotic fractures
BACKGROUND Osteoporotic fractures among the elderly are common , and without preventive measures the burden of these fractures on health-care systems will increase further . The purpose of this r and omised controlled study was to evaluate , in premenopausal women , the effects of high-impact loading on several determinants osteoporotic fractures . METHODS 98 healthy , sedentary female volunteers aged 35 - 45 years were r and omly assigned to either a training ( n = 49 ) or a control group ( n = 49 ) . Progressive high-impact exercises were done three times per week for 18 months . We measured bone mineral density ( BMD ) in specific axial and lower-limb sites , by dual-energy X-ray absorptiometry , at baseline and after 12 and 18 months . Maximum isometric strength , muscular and cardiovascular performance , and dynamic balance were also assessed . FINDINGS BMD at the femoral neck , a weightbearing site , increased significantly more in the training group ( mean 1.6 % [ 95 % CI 0.8 - 2.4 ] ) than in the control group ( 0.6 % [ -0.2 to 1.4 ] , p = 0.006 ) . By contrast , at non-weightbearing sites , such as the distal radius , there was no significant difference between the training and control groups ( -1.5 % [ -2.7 to -0.3 ] vs -0.7 % [ -1.9 to -0.5 ] , p = 0.60 ) . In the training group there was a significant improvement in vertical jump and predicted oxygen consumption per min at maximum exercise compared with controls . INTERPRETATION High-impact exercises that load bones with a rapidly rising force profile in versatile movements improve skeletal integrity , muscular performance , and dynamic balance in premenopausal women . If done on a regular basis , this type of exercise may help decrease the risk of osteoporotic fractures in later life . Long-term studies are required to show whether these 18-month results can be translated into long-term benefit
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 ) .