Evaluation of repetitive isometric contractions on the heads of triceps brachii muscle during grip force exercise

Abstract

OBJECTIVES: Normally, surface electromyography electrodes are used to evaluate the activity of superficial muscles during various kinds of voluntary contractions of muscle fiber. The objective of the present study was to investigate the effect of repetitive isometric contractions on the three heads of the triceps brachii muscle during handgrip force exercise. METHODS: Myoelectric signals were recorded from the lateral, long and medial heads of the triceps brachii muscle in 13 healthy males during maximal isometric contractions for 10 s of concurrent handgrip force and elbow extension. The subjects were asked to perform their contraction task five times with 3 minutes interval between two successive contractions. RESULTS: Decreasing electromyographic activities were found for the lateral and long heads, and increasing for the medial head throughout the 5 different contractions. Electromyographic activities were found for the lateral head with mean = 199.84, SD = 7.65, CV = 3.83%, the long head with mean = 456.76, SD = 18.10, CV = 3.96%, and the medial head with mean = 505.16, SD = 8.47, CV = 1.68%. Electromyographic activities among the three heads of triceps brachii were significantly different (F = 3.82) at the alpha level of (p < 0.05). CONCLUSIONS: These findings support that repetitive isometric contractions decrease the contractile activity in the lateral and long heads, and increases in the medial head of the triceps brachii muscle during handgrip force exercise with full elbow extension, and the electromyographic activity changes are observed to be more significant at the long head as compared to the lateral and medial heads.

Corticospinal excitability to the biceps and triceps brachii during forward and backward arm cycling is direction- and phase-dependent

“…The lack of phase-dependent changes 434 in CSE to the triceps brachii was not unexpected given our prior reports, albeit they only compared 435 The lower spinal excitability to the triceps brachii during BWD cycling in the current study 466 is unlikely to result solely from peripheral factors arising from differences in shoulder position. 467 This is because in the current study we recorded the activity of the lateral head of the triceps 468 brachii, which is a monoarticular muscle that does not cross the shoulder joint and is primarily 469 responsible for extending the elbow (Ali et al 2014). It is unlikely that shoulder flexion would 470 alter the muscle membrane properties (i.e.…”

The Neurovascular Structures in the Triangular Space of the Upper Limb: An Anatomical Study

“…There is an anatomical study that assesses nerve innervations of the long head of triceps brachii, but we did not identify the vascular system (Rezzouk et al, 2002). The three heads of triceps brachii generally have different functions at movement (Ali et al, 2015), and among them, the long head of triceps brachii is more active than the medial and lateral heads during handgrip force exercise with full elbow extension (Ali et al, 2014). We assessed the blood supply to the long head of triceps brachii because it was difficult to find a reference.…”

Corticospinal excitability to the biceps and triceps brachii during forward and backward arm cycling is direction- and phase-dependent

“…The lower spinal excitability to the triceps brachii during BWD cycling in the current study is unlikely to result solely from peripheral factors arising from differences in shoulder position. This is because in the current study we recorded the activity of the lateral head of the triceps brachii, which is a monoarticular muscle that does not cross the shoulder joint and is primarily responsible for extending the elbow (Ali et al 2014). It is unlikely that shoulder flexion would alter the muscle membrane properties (i.e.…”