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Figure 6 | Journal of NeuroEngineering and Rehabilitation

Figure 6

From: Predicting non-isometric fatigue induced by electrical stimulation pulse trains as a function of pulse duration

Figure 6

Average linear regression coefficients of determination (r2; ± 95% confidence limit) for predicted versus measured angular excursion and velocity of all contractions (50CFT, 12.5VFT and 33CFT). The non-isometric force-motion-fatigue model accounted for 66-81% of the variability in fatigue during general non-isometric leg extensions. Isometric force-time integral at 90° (iso) is shown for comparison. In A. n of gray bars = 13 model development subjects (note that only 170, 200, and 600 μs were used for model development) and n of black bars = 12 model validation subjects. Applied load was 4.54 kg. In B. n = 10 model validation subjects (pulse duration = 600 μs). ψ0 - compared to 0 kg (0.001≤p<0.05); ψ - compared to all 5 pulse durations (0.0001≤p< 0.02). Because the greatest potentiation occurred during the 0 kg load tests and because the force-motion-fatigue model does not include a term for potentiation, predicted excursions and velocities were lower than the measured values for 0 kg.

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