Verbal and visual stimulation effects on rectus femoris and biceps femoris muscles during isometric and concentric

Abstract

BackgroundCoactivation may be both desirable (injury prevention) or undesirable (strength measurement). In this context, different styles of muscle strength stimulus have being investigated. In this study we evaluated the effects of verbal and visual stimulation on rectus femoris and biceps femoris muscles contraction during isometric and concentric.MethodsWe investigated 13 men (age =23.1 ± 3.8 years old; body mass =75.6 ± 9.1 kg; height =1.8 ± 0.07 m). We used the isokinetic dynamometer BIODEX device and an electromyographic (EMG) system. We evaluated the maximum isometric and isokinetic knee extension and flexion at 60°/s. The following conditions were evaluated: without visual nor verbal command (control); verbal command; visual command and; verbal and visual command. In relation to the concentric contraction, the volunteers performed five reciprocal and continuous contractions at 60°/s. With respect to isometric contractions it was made three contractions of five seconds for flexion and extension in a period of one minute.ResultsWe found that the peak torque during isometric flexion was higher in the subjects in the VVC condition (p > 0.05). In relation to muscle coactivation, the subjects presented higher values at the control condition (p > 0.05).ConclusionWe suggest that this type of stimulus is effective for the lower limbs.

Verbal Encouragement and Between-Day Reliability During High-Intensity Functional Strength and Endurance Performance Testing

“…In contrast to our experienced sample of HIFT athletes, novice athletes may show greater differences in squat strength depending on technical and motivational deficiencies (Silva et al, 2013). In this regard, Argus et al (2011) stated that psychological interventions may have greater potential to affect performance in untrained or novice athletes.…”

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