Table 1.
Participant characteristicsa
| Characteristic | RUN | RUN+MDS | P value |
|---|---|---|---|
| Demographics | |||
| n | 14 | 18 | |
| Age (yrs) | 21.0 ± 1.6 | 20.6 ± 1.6 | 0.46 |
| BSI history (no/yes) | 5 / 9 | 10 / 8 | 0.26 |
| BSIs per athlete (n) | 1.4 ± 1.7 | 0.7 ± 0.8 | 0.14 |
| Age of menarche (yr) | 13.5 ± 1.7 | 13.3 ± 1.5 | 0.77 |
| LEAF-Q score | 7.3 ± 4.2 | 7.3 ± 5.0 | 0.99 |
| LEAF-Q score ≥8 (yes/no) | 7 / 7 | 7 / 11 | 0.40 |
| <9 menstrual cycles in past year (yes/no) | 3 / 11 | 3 / 15 | 0.73 |
| Past history of menstrual dysfunction >3 mths (yes/no) | 5 / 9 | 9 / 9 | 0.42 |
| Age started cross country (yr) | 11.2 ± 1.7 | 11.7 ± 2.8 | 0.60 |
| Total years of cross country (yr) | 9.8 ± 2.3 | 8.9 ± 3.0 | 0.38 |
| Best cross country 5 km time (mm:ss) | 18:34 ± 00:38 | 18:21 ± 00:47 | 0.46 |
| Age started MDS (yr) | — | 5.8 ± 1.9 | — |
| Years playing MDS before menarche (yr) | — | 7.7 ± 2.4 | — |
| Total years played MDS (yr) | — | 10.3 ± 3.2 | — |
| Whole-body anthropometry | |||
| Height (m) | 1.65 ± 0.06 | 1.67 ± 0.06 | 0.36 |
| Mass (kg) | 57.0 ± 4.2 | 59.9 ± 5.4 | 0.10 |
| Body mass index (kg/m2) | 20.9 ± 1.6 | 21.4 ± 1.9 | 0.39 |
| Whole-body aBMD (g/cm2)b | 0.890 ± 0.041 | 0.942 ± 0.072 | 0.02* |
| Whole-body aBMD z score | −0.30 (−0.67 to 0.08) | 0.09 (−0.37 to 0.55) | |
| Lean mass (kg) | 39.3 ± 4.1 | 41.7 ± 3.6 | 0.09 |
| Fat mass (%) | 21.2 ± 5.1 | 21.5 ± 4.3 | 0.84 |
| Regional anthropometry | |||
| Lumbar spine aBMD (g/cm2)b | 1.015 ± 0.110 | 1.096 ± 0.128 | 0.05* |
| Lumbar spine aBMD z score | −0.45 (−0.85 to −0.04)† | 0.18 (−0.23 to 0.58) | |
| Hip aBMD (g/cm2)b | 1.095 ± 0.091 | 1.138 ± 0.129 | 0.31 |
| Hip aBMD z score | 1.06 (0.62 to 1.50)† | 1.60 (1.14 to 2.07)† | |
| Distal radius HRpQCT outcomes c | |||
| Cortical thickness (mm)d | 0.88 ± 0.16 | 0.91 ± 0.13 | 0.56 |
| Cortical thickness z score | 0.09 (−0.53 to 0.72) | 0.30 (−0.15 to 0.75) | |
| Trabecular BV/TV (%)b | 23.1 ± 4.4 | 24.8 ± 4.7 | 0.31 |
| Trabecular BV/TV z score | −0.05 (−0.58 to 0.49) | 0.29 (−0.21 to 0.80) | |
| Failure load (kN)d | 5.33 ± 0.73 | 5.83 ± 1.04 | 0.14 |
| Failure load z score | −0.21 (−0.56 to 0.13) | 0.28 (−0.22 to 0.78) | |
| Radial diaphysis HRpQCT outcomes e | |||
| Total area (mm2)d | 86.9 ± 8.1 | 89.3 ± 10.2 | 0.47 |
| Total area z score | −0.33 (−0.70 to 0.05) | −0.16 (−0.55 to 0.23) | |
| Cortical thickness (mm)d | 3.19 ± 0.25 | 3.33 ± 0.24 | 0.13 |
| Cortical thickness z score | −0.34 (−0.86 to 0.18) | 0.15 (−0.28 to 0.58) | |
| Polar moment of inertia (mm4)d,f | 1246 ± 168 | 1334 ± 303 | 0.34 |
aBMD = areal bone mineral density; BSI = bone stress injury; BV/TV = bone volume per tissue volume; HRpQCT = high-resolution peripheral quantitative computed tomography; LEAF-Q = Low Energy Availability in Females Questionnaire; MDS = multidirectional sport
Data are mean ± SD, except for BSI history and LEAF-Q score ≥8 [frequencies] and z scores [mean (95% confidence interval)]
Values adjusted for LEAF-Q score and whole-body lean mass
Select outcomes at the distal radius. See Supplementary figures 1 & 2 for full data
Values adjusted for LEAF-Q score, whole-body lean mass, and bone length
Select outcomes at the radial diaphysis. See Supplementary figures 3 & 4 for full data
Normative reference data for this outcome is not available
Significant difference between groups (p<0.05)
Confidence interval does not cross zero