Determinants of Frame Running capacity in athletes with cerebral palsy to improve training routines and classification strategies: A cross-sectional observational study.

OBJECTIVE: Investigate 1) what physical and physiological parameters are most important for Frame Running (FR) capacity, a parasport for individuals with ambulatory difficulties, and 2) determine if FR capacity can be predicted in athletes with cerebral palsy (CP).

DESIGN: Athletes with CP (n = 62, GMFCS I-V; 2/26/11/21/2) completed a 6-minute FR test (6-MFRT). Before the 6-MFRT, muscle thickness, passive range of motion (hip, knee, ankle), selective motor control, and spasticity (hip, knee, ankle) were measured in both legs. In total, 54 variables per individual were included. Data were analyzed using correlations, Principal Component Analysis (PCA), Orthogonal Partial Least Square (OPLS) regression, and Variable Importance in Projection (VIP) analysis.

RESULTS: Mean 6-MFRT distance was 789 ± 335 m and decreased with motor function severity. The OPLS analysis revealed a modest degree of covariance in the variables analyzed, and that the variance in the 6-MFRT distance could be predicted with 75% accuracy based on all the variables measured. VIP analysis indicated hip and knee extensor spasticity (negative effect), and muscle thickness (positive effect) arose as the most important factors contributing to FR capacity.

CONCLUSIONS: These results are an important resource to enable optimization of training regimes to improve FR capacity and contribute to evidence-based and fair classification for this parasport.