***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: IMPORTANCE Bone accrual during youth is critical to establish sufficient strength for lifelong skeletal health . Children with cancer may develop low bone mineral density ( BMD ) any time before or after diagnosis . OBJECTIVE To evaluate the ability of low-magnitude , high-frequency mechanical stimulation to enhance BMD among childhood cancer survivors . DESIGN , SETTING , AND PARTICIPANTS Double-blind r and omized clinical trial conducted at St Jude Children 's Research Hospital from June 1 , 2010 , to January 22 , 2013 , using cancer survivors , ages 7 to 17 years , who were previously treated at St Jude Children 's Research Hospital , were in remission , and at least 5 years from diagnosis , with whole-body or lumbar spine BMD z scores of -1.0 or lower . Participants were r and omized ( stratified by sex and Tanner stage ) to either a placebo device or low-magnitude , high-frequency mechanical stimulation device , which was used at home . INTERVENTIONS Placebo or low-magnitude , high-frequency mechanical stimulation ( 0.3 g ; 32 - 37 Hz ) for 2 sessions lasting 10 minutes each , 7 days per week for 1 year . All participants were prescribed daily cholecalciferol ( vitamin D ) and calcium . MAIN OUTCOMES AND MEASURES Changes in areal and volumetric BMD and bone biomarkers were compared by analysis of variance , adjusted for strata . RESULTS Of the 65 participants , 32 were r and omized to the intervention group ( mean [ SD ] age was 13.6 [ 3.7 ] years , 18 [ 56.2 % ] were male , and 27 [ 84.4 % ] were white ) , and 33 were r and omized to the placebo group ( mean [ SD ] age was 13.6 [ 2.9 ] years , 17 [ 51.5 % ] were male , and 26 [ 78.8 % ] were white ) . Forty-eight participants completed the trial , 22 in the intervention group and 26 in the placebo group with median adherence of 70.1 % for intervention and 63.7 % for placebo groups . With intention-to-treat analysis , mean ( SD ) whole-body BMD z score by dual x-ray absorptiometry improved by 0.25 ( 0.78 ) in the intervention ( n = 22 ) , but decreased by -0.19 ( 0.79 ) in the placebo group ( n = 26 , P = .05 ) . Circulating osteocalcin at 12 months correlated with change in total body BMD ( r = 0.35 , P = .02 ) . Tibial trabecular bone among participants completing 70 % or more of the prescribed sessions increased by a mean of 11.2 % ( 95 % CI , 5.2 to 17.2 % ) compared with those completing less than 70 % who decreased by a mean of -1.3 % ( 95 % CI , -7.3 to 4.7 % ; P = .02 ) . Change in circulating receptor activator of nuclear factor κ-B lig and was higher in the intervention than in the placebo group ( 0.06 [ 0.16 ] vs -0.04 [ 0.17 ] pmol/L ) ( P = .04 ) . CONCLUSIONS AND RELEVANCE Pediatric cancer survivors with low BMD may benefit from low-magnitude , high-frequency mechanical stimulation as a novel and safe intervention to optimize peak bone mass during youth , alone or in conjunction with other therapies . TRIAL REGISTRATION clinical trials.gov Identifier : NCT01010230 There is limited information on body composition , energy balance , and fitness among survivors of childhood acute lymphoblastic leukemia ( ALL ) , especially those treated without cranial radiation therapy ( CRT ) .  This analysis compares these metrics among 365 ALL survivors with a mean age of 28.6 ± 5.9 years ( 149 treated with and 216 without CRT ) and 365 age- , sex- , and race-matched peers . We also report risk factors for outcomes among survivors treated without CRT . Male survivors not exposed to CRT had abnormal body composition when compared with peers ( % body fat , 26.2 ± 8.2 vs 22.7 ± 7.1 ) . Survivors without CRT had similar energy balance but had significantly impaired quadriceps strength ( -21.9 ± 6.0 Newton-meters [Nm]/kg , 60 ° /s ) and endurance ( -11.4 ± 4.6 Nm/kg , 300 ° /s ) , exercise capacity ( -2.0 ± 2.1 ml/kg per minute ) , low-back and hamstring flexibility ( -4.7 ± 1.6 cm ) , and dorsiflexion range of motion ( -3.1 ± 0.9 ° ) and higher modified total neuropathy scores ( + 1.6 ± 1.1 ) than peers . Cumulative asparaginase dose ≥120,000 IU/m(2 ) was associated with impaired flexibility , vincristine dose ≥39 mg/m(2 ) with peripheral neuropathy , glucocorticoid ( prednisone equivalent ) dose ≥8000 mg/m(2 ) with h and weakness , and intrathecal methotrexate dose ≥225 mg with dorsiflexion weakness . Physical inactivity was associated with h and weakness and decreased exercise capacity . Smoking was associated with peripheral neuropathy . Elimination of CRT from ALL therapy has improved , but not eliminated , body-composition outcomes . Survivors remain at risk for impaired fitness [ Purpose ] This study evaluated the immediate and short-term effects of a combination of prolonged passive muscle stretching ( PMS ) and whole body vibration ( WBV ) on the spasticity , strength and balance of children and adolescents with cerebral palsy . [ Subjects and Methods ] A r and omized two-period crossover trial was design ed . Twelve subjects with cerebral palsy aged 10.6 ± 2.4 years received both PMS alone as a control group ( CG ) and a combination of PMS and WBV as an experimental group ( EG ) . After r and om allocation to the trial schedules of either EG-CG or CG-EG , CG received prolonged PMS while st and ing on a tilt-table for 40 minutes/day , and EG received prolonged PMS for 30 minutes , followed by 10 minutes WBV . Both CG and EG received the treatment 5 days/week for 6 weeks . [ Results ] Immediately after one treatment , EG result ed in better improvement in scores on the Modified Ashworth Scale than CG . After the 6-week intervention , EG also showed significantly decreased scores on the Modified Ashworth Scale compared to CG . Both CG and EG showed significantly reduced the performance times in the five times sit to st and test , and EG also showed significantly increased scores on the pediatric balance scale . [ Conclusion ] This study showed that 6 weeks of combined prolonged PMS and WBV had beneficial effects on the spasticity , muscle strength and balance of children and adolescents with CP Background Children with cerebral palsy ( CP ) have decreased strength , low bone mass , and an increased propensity to fracture . High-frequency , low-magnitude vibration might provide a noninvasive , nonpharmacologic , home – based treatment for these musculoskeletal deficits . The purpose of this study was to examine the effects of this intervention on bone and muscle in children with CP . Methods Thirty-one children with CP ages 6 to 12 years ( mean 9.4 , SD 1.4 ) stood on a vibrating platform ( 30Hz , 0.3 g peak acceleration ) at home for 10 min/d for 6 months and on the floor without the platform for another 6 months . The order of vibration and st and ing was r and omized , and outcomes were measured at 0 , 6 , and 12 months . The outcome measures included computed tomography measurements of vertebral cancellous bone density ( CBD ) and cross-sectional area , CBD of the proximal tibia , geometric properties of the tibial diaphysis , and dynamometer measurements of plantarflexor strength . They were assessed using mixed model linear regression and Pearson correlation . Results The main difference between vibration and st and ing was that there was a greater increase in the cortical bone properties ( cortical bone area and moments of inertia ) during the vibration period ( all P's⩽0.03 ) . There was no difference in cancellous bone or muscle between vibration and st and ing ( all P's>0.10 ) and no correlation between compliance and outcome ( all r's<0.27 ; all P's>0.15 ) . The results did not depend on the order of treatment ( P>0.43 ) and were similar for children in gross motor function classification system ( GMFCS ) 1 to 2 and GMFCS 3 to 4 . Conclusions The primary benefit of the vibration intervention in children with CP was to the cortical bone in the appendicular skeleton . Increased cortical bone area and the structural ( strength ) properties could translate into a decreased risk of long bone fractures in some patients . More research is needed to corroborate these findings , to eluci date the mechanisms of the intervention , and to determine the most effective age and duration of the treatment . Level of Evidence Level II , prospect i ve r and omized cross-over study In this 6-month trial , twenty children with cerebral palsy ( age 6.2 to 12.3 years ; 6 girls ) were r and omized to either continue their school physiotherapy program unchanged or to receive 9 minutes of side-alternating whole-body vibration ( WBV ; Vibraflex Home Edition II , Orthometrix Inc ) per school day in addition to their school physiotherapy program . Patients who had received vibration therapy increased the average walking speed in the 10 m walk test by a median of 0.18 ms(-1 ) ( from a baseline of 0.47 ms(-1 ) ) , whereas there was no change in the control group ( P=0.03 for the group difference in walking speed change ) . No significant group differences were detected for changes in areal bone mineral density ( aBMD ) at the lumbar spine , but at the distal femoral diaphysis aBMD increased in controls and decreased in the WBV group ( P=0.03 for the group difference in aBMD change ) . About 1 % of the WBV treatment sessions were interrupted because the child complained of fatigue or pain . In conclusion , the WBV protocol used in this study appears to be safe in children with cerebral palsy and may improve mobility function but we did not detect a positive treatment effect on bone Objective : To evaluate ambulatory function and leg muscle thickness after whole body vibration training in children with cerebral palsy . Design : A block r and omized controlled trial with two groups . Setting : Physical therapy department laboratory . Subjects : A total of 30 ( 15 experimental , mean ( SD ) age 10.0 ( 2.26 ) years and 15 control , 9.6 ( 2.58 ) ) children with cerebral palsy , 15 males and 15 females . Interventions : The experimental group underwent whole body vibration training combined with conventional physical therapy training ; the control group underwent conventional physical therapy training three days a week for eight weeks respectively . Main outcome measures : Three-dimensional gait analyses and ultrasonographic imaging of the leg muscles were measured at pre- and post-test of intervention for eight weeks . Results : Whole body vibration training result ed in significantly better gait speed ( P = 0.001 , from 0.37 ( 0.04 ) m/s to 0.48 ( 0.06 ) ) , stride length ( P = 0.001 , from 0.38 ( 0.18 ) m to 0.48 ( 0.18 ) ) and cycle time ( P = 0.001 , from 0.85 ( 0.48 ) s to 0.58 ( 0.38 ) ) in the experimental group compared with that in the control group . The ankle angle ( P = 0.019 , from 7.30 ( 4.02 ) degree to 13.58 ( 8.79 ) ) also showed a remarkable increase in the experimental group , but not the hip ( P = 0.321 ) and knee angle ( P = 0.102 ) . The thicknesses of the tibialis anterior ( P = 0.001 , 0.48 ( 0.08 ) mm to 0.63 ( 0.10 ) ) and soleus ( P = 0.001 , 0.45 ( 0.04 ) mm to 0.63 ( 0.12 ) ) muscles were significantly higher in the experimental group than in the control group . However , no significant effect was observed in the thickness of the gastrocnemius muscle ( P = 0.645 ) . Conclusions : These findings suggest that whole body vibration may improve mobility in children with cerebral palsy , probably through a positive effect on the leg muscles Introduction There is a lack of data on  physical activity ( PA ) and fitness of adolescent and young adult very long-term survivors of childhood acute lymphoblastic leukemia ( ALL ) . Methods We studied 21 childhood ALL long-term survivors ( aged 16–30 years , median time since diagnosis 15.9y ) , diagnosed in 1986–1996 , with age- and sex-matched controls . Peak oxygen uptake ( VO2 
    Output:
    
Results demonstrate that WBV is a safe , highly compliant , and effective approach in cohorts of children with disabilities .
The largest effects of WBV were observed in lower extremity muscle mass and strength , balance control , gait , and walking ability .
Furthermore , we were able to develop first recommendations for WBV protocol s. Conclusions WBV seems to be feasible and effective for improving parameters that may be relevant to the pediatric cancer population .