The effect of 18 months of training on the ovarian hormone concentrations and bone mineral density (BMD) accrual was assessed longitudinally in 14 adolescent rowers and 10 matched controls, aged 14-15 years. Ovarian hormone levels were assessed by urinary estrone glucuronide (E(1)G) and pregnanediol glucuronide (PdG) excretion rates, classifying the menstrual cycles as ovulatory or anovulatory. Total body (TB), total proximal femur (PF), femoral neck (FN) and lumbar spine (LS) (L2-4) bone mass were measured at baseline and 18 months using dual-energy X-ray densitometry. Results were expressed as bone mineral content (BMC), BMD and bone mineral apparent density (BMAD). Five rowers had anovulatory menstrual cycles compared with zero prevalence for the control subjects. Baseline TB BMD was significantly higher in the ovulatory rowers, with PF BMD, FN BMD and LS BMD similar for all groups. At completion, the LS bone accrual of the ovulatory rowers was significantly greater (BMC 8.1%, BMD 6.2%, BMAD 6.2%) than that of the anovulatory rowers (BMC 1.1%, BMD 3.9%, BMAD 1.6%) and ovulatory controls (BMC 0.5%, BMD 1.1%, BMAD 1.1%). No difference in TB, PF or FN bone accrual was observed among groups. This study demonstrated an osteogenic response to mechanical loading, with the rowers accruing greater bone mass than the controls at the lumbar spine. However, the exercise-induced osteogenic benefits were less when rowing training was associated with low estrogen and progesterone metabolite excretion.
This research output has an Altmetric Attention Score of 3. 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 29 September 2003.
All research outputs
#7,481,847
of 22,870,727 outputs
Outputs from Osteoporosis International
#1,343
of 3,616 outputs
Outputs of similar age
#11,015
of 35,027 outputs
Outputs of similar age from Osteoporosis International
#8
of 12 outputs
Altmetric has tracked 22,870,727 research outputs across all sources so far. This one is in the 44th percentile – i.e., 44% of other outputs scored the same or lower than it.
So far Altmetric has tracked 3,616 research outputs from this source. They typically receive more attention than average, with a mean Attention Score of 7.6. This one has gotten more attention than average, scoring higher than 50% of its peers.
Older research outputs will score higher simply because they've had more time to accumulate mentions. To account for age we can compare this Altmetric Attention Score to the 35,027 tracked outputs that were published within six weeks on either side of this one in any source. This one is in the 9th percentile – i.e., 9% of its contemporaries scored the same or lower than it.
We're also able to compare this research output to 12 others from the same source and published within six weeks on either side of this one. This one is in the 8th percentile – i.e., 8% of its contemporaries scored the same or lower than it.
