Effect of two jumping programs on hip bone mineral density in premenopausal women: a randomized controlled trial.
OBJECTIVE
To determine the effect of two jumping programs on hip bone mineral density (BMD) in women.


METHODS
Randomized controlled trial.


METHODS
Approximately 20 cities in the Mountain West.


METHODS
Sixty premenopausal women, aged 25 to 50 years, completed the intervention.


METHODS
Subjects were randomly assigned to a control group or one of two jumping groups. The Jump 10 group performed 10 jumps with 30 seconds rest between jumps, twice daily for 16 weeks, while the Jump 20 group performed the same protocol but with 20 jumps.


METHODS
Hip BMD was measured by using dual-energy x-ray absorptiometry.


METHODS
Analysis of variance and covariance.


RESULTS
At 8 weeks, unadjusted percentage change in hip BMD was significantly different among groups (F = 5.4, p = .0236). Specifically, compared with controls, the Jump 20 women had significantly greater gains in hip BMD and the Jump 10 women had marginally greater improvements. Following 16 weeks of jumping, differences between the Jump 10 and the Jump 20 groups compared with controls were significant (F = 4.2, p = .0444), especially after adjusting for the covariates (F = 7.3, p = .0092).


CONCLUSIONS
After 16 weeks of high-impact jump training, hip BMD can be improved in premenopausal women by jumping 10 or 20 times, twice daily, with 30 seconds of rest between each jump, compared with controls.
Larry A
LA
Tucker
J Eric
JE
Strong
James D
JD
LeCheminant
Bruce W
BW
Bailey
D015502:Absorptiometry, Photon; D000328:Adult; D000367:Age Factors; D001835:Body Weight; D015519:Bone Density / Q000502:physiology*; D002136:Calcium, Dietary; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D008875:Middle Aged; D017697:Premenopause / Q000502:physiology*; D013997:Time Factors; D014481:United States
D002136:Calcium, Dietary
Bone Mineral Density; Exercise; Fracture; Health focus: osteoporosis; Hip; Impact; Jump; Manuscript format: research; Osteoporosis; Outcome measure: biometric; Prevention Research; Research purpose: intervention testing; Setting: several communities; Strategy: behavior change; Study design: randomized trial; Target population circumstances: education/income level, race/ethnicity; Target population: adults