Concurrent Augmented Feedback and Isometric Force Generation during Familiar and Unfamiliar Muscle Movements

Abstract

To evaluate the effect of concurrent augmented feedback on isometric force output during familiar and unfamiliar muscle movements, 18 men and 21 women, 18 to 23 years of age, completed two isometric exercises: flexion of the thumb (a familiar muscle movement) and abduction of the fifth digit (an unfamiliar movement). The exercises consisted of 10 maximum voluntary isometric contractions lasting 10 s each and separated by 10-s intertrial rest intervals. Concurrent visual feedback was provided during alternate contractions. The order of exercises and trials for feedback was randomly assigned and balanced over subjects. Peak force output during abduction of the fifth digit was significantly (p less than or equal to .01) greater with (4.4 +/- 0.29 kg) than without feedback (4.1 +/- 0.26 kg). Feedback did not influence (p greater than .05) peak force output during thumb flexion (23.2 +/- 1.09 kg vs 22.5 +/- 1.05 kg). Muscular fatigue was more pronounced during thumb flexion without feedback (18.4 +/- 1.17%) than when feedback was provided (11.8 +/- 1.36%). These data suggest that fatigue may increase the effect of feedback on force generation during familiar muscular movements. To obtain maximal isometric force measures during strength testing, augmented feedback should be provided.

Clinical evaluator reliability for quantitative and manual muscle testing measures of strength in children

“…Comparison of our results with previous studies suggests that the use of a motivational tool tailored specifically for children, an audiovisual feedback video game, significantly improves the reliability of QMT results. Although we did not measure QMT reliability with and without visual feedback, the positive effect of external feedback on motor performance has previously been reported 6, 13, 16, 17. Specifically, the effect of visual feedback in the performance of isokinetic and isometric muscle force generation has been studied in children as young as 3 years of age as well as in adults,6 consistently showing an increase in the effectiveness of the measured task.…”

“…Specifically, the effect of visual feedback in the performance of isokinetic and isometric muscle force generation has been studied in children as young as 3 years of age as well as in adults,6 consistently showing an increase in the effectiveness of the measured task. However, the efficiency of visual feedback tends to decrease in adults as the task becomes familiar 13, 17. This phenomenon has not been observed in children.…”

Quantifying deficits in the 3D force capabilities of a digit caused by selective paralysis: application to the thumb with simulated low ulnar nerve palsy

“…2). Subjects performed the tasks with visual feedback to increase the likelihood that we captured maximal voluntary force production (Graves and James, 1990). While we displayed the subject's force vector with respect to the Fig.…”

Reliability of isometric subtalar pronator and supinator strength testing

“…Therefore, during MVIC measurement a biofeedback method was applied while the signal of the force transducer was displayed on the monitor. As suggested by James and Graves [33], supplementary FB helps to increase PT especially during unfamiliar contractions. We assumed that providing FB could enhance the reliability of pronator and supinator MVIC testing, as subjects would perform a more accurate triplanar subtalar motion and, consequently, come closer to approaching their individual strength capacity.…”