Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
3366017 | Joint Bone Spine | 2012 | 6 Pages |
ObjectivesTo analyse the relationship between isokinetic strength of the lower limb muscles and bone mineral density and content (BMD, BMC) of adolescent male soccer players and age-matched controls not involved in sport (12–15 years).MethodsA random sample of 151 young males was divided into soccer players (SG; n = 117) and control subjects (CG; n = 34). Peak torque of knee extensors (PTE) and flexors (PTF) was measured during isokinetic knee joint movement (90°/s) of the dominant and non-dominant lower limbs. BMD and BMC of the whole-body, lumbar spine, dominant/non-dominant lower limb were determined by dual-energy X-ray absorptiometry. Physical activity was monitored with accelerometers during 5 days. Estimated maturity offset was used as an indicator of biological maturity status.ResultsWhole-body BMD (1.03 ± 0.01 vs. 0.98 ± 0.01 g/cm2, P = 0.003) and dominant (1.09 ± 0.01 vs. 1.02 ± 0.01 g/cm2, P < 0.001) and non-dominant (1.09 ± 0.01 vs. 1.01 ± 0.01 g/cm2, P < 0.001) lower limb BMD was greater in SG compared to CG. No significant differences were found for BMC. Compared to CG, SG performed better in the YY-IE2 test (780 ± 40 vs. 625 ± 31 m), exhibited higher PTE (dominant limb: 155.2 ± 30.3 vs. 123.4 ± 37.0 N m; non-dominant limb: 156.2 ± 36.1 vs. 120.4 ± 41.1 N m) and PTF muscles (dominant limb: 79.0 ± 25.3 vs. 57.1 ± 25.3 Nm; non-dominant limb: 73.3 ± 20.7 vs. 57.0 ± 24.2 N m). Moreover, the PTE, soccer participation and maturity status were positively associated with the BMD at all body sites (r2 = 0.57–0.73, P < 0.05).ConclusionsMuscle strength of knee extensors is associated with BMD and BMC at all body sites. Muscle-skeletal structures respond positively to the weight-bearing and impact-loading imposed by soccer practice. Soccer seemed to be a multilateral balanced sport activity.