Table 4

Multiple linear regression analyses assessing predictors of total body and lumbar spine bone mass values in the runner (n=51) and non-runner (n=18) athletes

	Age	FFM	Mileage†	R²‡
Runners
Total body
BMD	NS	0.60^***	NS	0.54
BMC	0.26^*	0.75^***	NS	0.71
BMD Z-score	–	0.45^**	NS	0.14
Lumbar spine
BMD	0.54^**	NS	−0.43^**	0.30
BMC	0.36^*	0.56^***	−0.28^*	0.51
BMD Z-score	–	0.35^*	NS	0.11
Non-runners§
Total body
BMD	NS	0.77^**	–	0.68
BMC	NS	0.80^**	–	0.75
BMD Z-score	–	0.74^**	–	0.51
Lumbar spine
BMD	NS	0.67^**	–	0.70
BMC	NS	0.79^**	–	0.65
BMD Z-score	–	0.75^**	–	0.53

Multiple linear regression analysis, standardised beta coefficients, *** <0.001, **<0.01, *<0.05.
Model also adjusted for history of (1) stress fracture and (2) participation in a ball sport.
†Average weekly running mileage over the past year.
‡Adjusted R².
§Non-runner athletes did not report history of stress fracture and were not asked to report running mileage.
BMC, bone mineral content; BMD, bone mineral density; FFM, fat-free mass; NS, not significant.