Isokinetic muscular strength of paralympic athletes with cerebral palsy (CP) from the Brazilian soccer team

Introduction and objective: The muscle weakness, strength asymmetries and imbalance between antagonist muscles are risk factors for knee injuries. It is possible that these risk factors increase in soccer players with cerebral palsy (CP) due to their pathology and to the sport activity. Therefore, the objective of the present study was to assess the presence of these factors in paralympic athletes with CP from the Brazilian paralympic seven-a-side soccer team. Methodology: Twenty-one soccer players with CP and spastic hemiplegia were submitted to isokinetic muscle evaluation of their knees flexors and extensors muscles by means of the Cybex 6000 isokinetic dynamometer. The analysis of the muscle strength was performed with a peak torque at 60°/s. The study analyzed the contralateral deficit, the balance between flexor and extensor muscles and compared muscles weakness to the expected values for normal individuals (Neder et al. 1999). The paired tStudent test was used for the statistical analysis with p < 0.05. Results: The peak torque values of the involved flexors (FPT) and extensors (EPT) knee muscles (FPT = 88.4 ± 26.0 Nm and EPT 155.4 ± 37.2 Nm) presented significantly smaller ratios than those of the uninvolved ones (FPT = 116.2 ± 24.8 Nm and EPT = 201.6 ± 38.8 Nm). Only extensor muscles of the involved side were weaker than expected. However, the flexor muscles were weaker than expected in nine out of 21 individuals. The measures of strength of uninvolved knee muscles were not significantly different from the expected values. The average balance between flexors and extensors was within the normal range, although three individuals presented results below the normal range in the uninvolved side and nine of them in relation to the involved side. Conclusion: Highly trained soccer players with CP present increased risk factors to knee injuries derived from strength asymmetries, quadriceps muscle weakness and imbalance between antagonistic knee muscles. Thus, a muscular strengthening and evaluation program is highly indicated for this group.