Muscle activity and architecture as a predictor of hand-grip strength

Abstract

Background: Grip strength is a powerful predictor of disability as well as a good indicator of physical activity. Objectives: This study aimed to relate ultrasound (US) and electromyography (EMG) simultaneously to maximum hand-grip strength during an isometric contraction. Approach: This is a cross-sectional study. Data acquisition was done with a dynamometer, US and EMG. Outcome variables included maximum strength during the hand-grip gesture, maximum muscle activity and change in muscle thickness. A non-linear regression analysis was performed to analyse the relationship between all outcome variables. Main results: A total of 38 subjects (18 men and 20 women) participated in the study. The mean results for hand-grip strength were 25.50 (SD 6.55) kg of maximum strength, a change in muscle thickness of 1.83 (SD 0.75) mm and an EMG activity of 499.29 (SD 224.20) µV. Hand-grip strength had a high correlation with muscle thickness (R2 = 0.61) and EMG activity (R2 = 0.95). The correlation between maximum muscle activity and change in muscle thickness was R2 = 0.83. Significance: The results of the present study demonstrate that this new method based on electromyographic activity and muscule architecture could be important in the development of the hand-grip test.

Convergent Validity between Electromyographic Muscle Activity, Ultrasound Muscle Thickness and Dynamometric Force Measurement for Assessing Muscle

“…Participants had to be aged between 18 and 65 years and had to read and sign the informed consent form to be enrolled in the study. Exclusion criteria included (1) neurological, muscular, cardiovascular or any other condition contraindicating hand grip MVIC performance or contributing to pain appearance; (2) subjects with a body mass index (BMI) > 35 kg/m 2 since this could bias the US and EMG measurements [ 21 ].…”

“…Sample size was calculated based on the only previous similar study analyzing simultaneously MVIC, US and EMG [ 21 ] (peak, but not fatigue) in healthy subjects. Accordingly, a minimum sample size of 38 participants could be considered appropriate.…”

“…Previously, participants were familiarized with the dynamometer and the starting position (subjects placed the Jamar in their hand, with the arm beside the trunk, the shoulder in a neutral position and the elbow flexed at 90°, and pulled the metal bar with their fingers), performing 2–3 submaximal contractions (to avoid early fatigue appearance), as illustrated in Figure 1 . All procedures were conducted following the instructions described by Trinidad-Fernández et al [ 21 ], as they demonstrated acceptable reliability.…”

“…Despite previous research analyzing the association between US and EMG simultaneously with MVIC [ 21 ], evidence is limited regarding the convergent validity of these three methods for assessing simultaneously muscle fatigue during a sustained MVIC. Therefore, the aim of this study was to assess the association of the fatigue-adjusted line using US, EMG and dynamometry simultaneously during a sustained MVC to verify the association between isometric force capacity, electrical muscle activity and muscle morphology.…”

Design and implementation of a standard care programme of therapeutic exercise and education for breast cancer survivors

“…Finally, a functional assessment was provided by 30-STS [ 21 ], hand-grip strength [ 22 ], and the following questionnaires: Piper Fatigue Scale-Revised (PFS-R) [ 23 ], the Upper Limb Functional Index (ULFI) [ 24 ], the Lower Limb Functional Index (LLFI) [ 25 ], the International Physical Activity Questionnaire-Short Form (IPAQ-SF) [ 26 ], the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30) [ 27 ], and the European Organisation for Research and Treatment of Cancer Breast Cancer-Specific Quality of Life questionnaire (EORTC QLQ-BR23) [ 28 ].…”