| Title |
Self-reported ballet classes undertaken at age 10–12 years and hip bone mineral density in later life
|
|---|---|
| Published in |
Osteoporosis International, March 1998
|
| DOI | 10.1007/bf02672514 |
| Pubmed ID | |
| Authors |
K. M. Khan, K. L. Bennell, J. L. Hopper, L. Flicker, C. A. Nowson, A. J. Sherwin, K. J. Crichton, P. R. Harcourt, J. D. Wark |
| Abstract |
The major effect of weightbearing exercise on adult bone mass may be exerted during childhood. We examined the relationship between reported hours of ballet classes per week undertaken as a child and adult bone mineral density (BMD) at the hip, spine, and forearm. We performed a retrospective cohort study in 99 female retired dancers (mean age 51 years, SD 14 years) and 99 normal controls, derived from a twin study, matched hierarchically for age, height, weight and menopausal status. Starting age of ballet was recalled and weekly hours of ballet as a child was self-reported on two occasions. BMD was measured using dualenergy X-ray absorptiometry and reported as a Z-score. Self-reported hours of ballet class undertaken per week at each age between 10 and 12 years was positively associated with a difference in BMD between dancers and controls at both the femoral neck site (beta = 0.73, p = 0.001) and the total hip site (beta = 0.55, p < 0.01). These associations were unaffected by adjustment for covariates including measures of adult activity (current physical activity, years of fulltime ballet), measures of menstrual disturbance (age of menarche, history of irregular menses), dietary history (calcium intake as a child, adolescent or adult) or lifestyle factors (lifetime smoking, lifetime alcohol). Although starting age of ballet was negatively associated with weight-adjusted within-pair hip BMD difference, it was no longer associated after adjustment for weekly hours of ballet. There was no relationship between hours of ballet undertaken as a child and differences in BMD at the lumbar spine or upper limb, at any age. Our data suggest that classical ballet classes undertaken between the ages of 10 and 12 years are independently and positively associated with a difference in hip BMD between dancers and controls. The findings are consistent with the hypothesis that this age range identifies a stage of development when the proximal femur is particularly responsive to weightbearing exercise. |
Mendeley readers
The data shown below were compiled from readership statistics for 63 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Germany | 1 | 2% |
| Unknown | 62 | 98% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Student > Ph. D. Student | 14 | 22% |
| Student > Bachelor | 11 | 17% |
| Student > Master | 10 | 16% |
| Student > Doctoral Student | 7 | 11% |
| Researcher | 4 | 6% |
| Other | 8 | 13% |
| Unknown | 9 | 14% |
| Readers by discipline | Count | As % |
|---|---|---|
| Medicine and Dentistry | 16 | 25% |
| Sports and Recreations | 12 | 19% |
| Social Sciences | 5 | 8% |
| Psychology | 4 | 6% |
| Agricultural and Biological Sciences | 3 | 5% |
| Other | 9 | 14% |
| Unknown | 14 | 22% |
Attention Score in Context
This research output has an Altmetric Attention Score of 6. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 16 June 2012.
All research outputs
#4,710,483
of 22,851,489 outputs
Outputs from Osteoporosis International
#785
of 3,615 outputs
Outputs of similar age
#4,296
of 31,882 outputs
Outputs of similar age from Osteoporosis International
#2
of 15 outputs
Altmetric has tracked 22,851,489 research outputs across all sources so far. Compared to these this one has done well and is in the 76th percentile: it's in the top 25% of all research outputs ever tracked by Altmetric.
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We're also able to compare this research output to 15 others from the same source and published within six weeks on either side of this one. This one has done well, scoring higher than 80% of its contemporaries.