Effects of Single-Leg Drop-Landing Exercise from Different Heights on Skeletal Adaptations in Prepubertal Girls: A Randomized Controlled Study
| Autor: | Roberts Howman-Giles, Julie Briody, Damian Marsh, Nathalie Farpour-Lambert, Christopher T. Cowell, Peter N. Wiebe, Allan Kemp, Cameron J. R. Blimkie |
|---|---|
| Rok vydání: | 2008 |
| Předmět: |
medicine.medical_specialty
Bone density Posture Puberty/*physiology Leisure time Physiology Physical Therapy Sports Therapy and Rehabilitation Motor Activity law.invention Fat mass Absorptiometry Photon Randomized controlled trial Bone Density law Humans Medicine Orthopedics and Sports Medicine Muscle Skeletal/*physiology Exercise physiology Muscle Skeletal Adaptation Physiological Child Exercise Life Style Bone mineral Leg ddc:618 business.industry Puberty Exercise/*physiology Skeleton (computer programming) Body Height Institutional repository Pediatrics Perinatology and Child Health Exercise Test Physical therapy Body Height/*physiology Female business Leg/*physiology |
| Zdroj: | Pediatric Exercise Science, Vol. 20, No 2 (2008) pp. 211-228 |
| ISSN: | 1543-2920 0899-8493 |
| DOI: | 10.1123/pes.20.2.211 |
| Popis: | Few studies have explored osteogenic potential of prepubertal populations. We conducted a 28-week school-based exercise trial of single-leg drop-landing exercise with 42 prepubertal girls (6 to 10 yrs) randomly assigned to control (C), low-drop (LD) or high-drop (HD) exercise groups. The latter two groups performed single-leg drop-landings (3 sessions/wk−1 and 50 landings/session−1) from 14cm(LD) and 28cm(HD) using the nondominant leg. Osteogenic responses were assessed using Dual Energy X-ray Absorptiometry (DXA). Single-leg peak ground-reaction impact forces (PGRIF) in a subsample ranged from 2.5 to 4.4 × body-weight (BW). No differences (p > .05) were observed among groups at baseline for age, stature, lean tissue mass (LTM), leisure time physical activity, or average daily calcium intake. After adjusting for covariates of body mass, fat mass and LTM, no differences were found in bone mineral measures or site-specific bone mineral density (BMD) at the hip and lower leg among exercise or control groups. Combining data from both exercise groups failed to produce differences in bone properties when compared with the control group. No changes were apparent for between-leg differences from baseline to posttraining. In contrast to some reports, our findings suggest that strictly controlled unimodal, unidirectional single-leg drop-landing exercises involving low-moderate peak ground-reaction impact forces are not osteogenic in the developing prepubertal female skeleton. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|