RESUMEN
OBJECTIVE: To determine whether regular performance of adapted sports is associated with long-term changes in carotid atherosclerosis in subjects with spinal cord injury (SCI). DESIGN: Prospective observational study. SETTING: Academic medical center. PARTICIPANTS: Men with chronic (>1y) SCI and no preserved motor function below the injury level were evaluated in 2007 and 2012 (N=17). Nine subjects did not perform physical activity between the studied time points (control group), whereas 8 subjects entered competitive upper-body sports programs (rugby: n=5, basketball: n=1, jiu-jitsu: n=1, and tennis: n=1) after baseline and were regularly training at the time of the second evaluation (sports group). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Clinical, laboratory, hemodynamic, and carotid ultrasonography analysis. RESULTS: The studied groups showed no differences in all studied variables at baseline. After 5 years of follow-up, the control group showed increases in heart rate (87.0±3.1 vs 74.7±3.8 beats per minute; P=.004), but the participants had no significant changes in carotid intima-media thickness (IMT) (.65±.05 vs .67±.03mm; P=.73) or IMT/diameter (.118±.007 vs .136±.013; P=.24). In contrast, the sports group showed long-term decreases in carotid IMT (.56±.05 vs .74±.05mm; P=.001) and IMT/diameter (.097±.006 vs .141±.009; P<.001), but the participants did not show any variation in the other studied variables at follow-up. CONCLUSIONS: Regular upper-body sports activities are associated with long-term reductions in carotid atherosclerosis in subjects with SCI and might be a potential prevention strategy aiming to reduce cardiovascular risk in this population.
Asunto(s)
Enfermedades de las Arterias Carótidas/fisiopatología , Ejercicio Físico/fisiología , Traumatismos de la Médula Espinal/rehabilitación , Deportes/fisiología , Centros Médicos Académicos , Grosor Intima-Media Carotídeo , Frecuencia Cardíaca , Humanos , Masculino , Estudios Prospectivos , Factores de RiesgoRESUMEN
BACKGROUND: The cardiorespiratory responses and mechanical efficiencies of two modalities of functional electrical stimulation augmented leg exercises - isokinetic cycling and isokinetic elliptical stepping - were compared amongst individuals with spinal cord injury. METHODS: Five subjects performed seated isokinetic evoked cycling and elliptical stepping leg exercise at 10, 20 and 30rev·min(-1) pedal cadences. 3-D motion analysis and force transducers attached onto the foot pedals quantified the external forces and power outputs developed by each lower extremity. Hip, knee and ankle joints power were derived via inverse dynamics analysis. The subjects' cardiorespiratory responses during exercise were measured by respiratory gas analysis. FINDINGS: Ensemble-averaged oxygen uptakes across pedal cadences were higher during stepping (448 (75) ml·min(-1)) compared to cycling (422 (54) ml·min(-1)). External power outputs and metabolic efficiencies during stepping (9.9 (8.3) W, 2.9 (3.2) %) were double those observed during cycling (5.3 (6.3) W, 1.6 (1.9) %). Cumulative internal and external leg joint powers during stepping were twice higher than cycling, but the stepping mechanical efficiencies derived from inverse dynamics analysis were comparable to cycling (76.3 (21.2) % and 63.6 (12.3) % respectively). Heart rate responses were similar between cycling and stepping, while carbon dioxide production and expired ventilation were slightly higher during elliptical stepping. INTERPRETATION: Both exercise modalities could deliver appropriate training stimuli for improving the aerobic fitness and leg pedalling strength of spinal cord-injured individuals. However electrical stimulation-enhanced elliptical stepping might provide greater exercise dose-potency for leg muscle strengthening than electrically-enhanced cycling due to the higher power outputs observed.