Optimal Normalization Tests for Muscle Activation of the Levator Scapulae, Pectoralis Minor, and Rhomboid Major: An Electromyography Study Using Maximum Voluntary Isometric Contractions

Muscular workload of veterinary students during simulated open and laparoscopic surgery: A pilot study*

“…Three maximum voluntary contraction (MVC) measurements were obtained from each muscle group before completing the simulated surgery tasks, as a baseline for normalization of subsequent EMG data . Briefly, an investigator applied manual resistance to each isolated muscle group as the participant exerted maximal force against it via ramped isometric muscle contraction.…”

“…Briefly, an investigator applied manual resistance to each isolated muscle group as the participant exerted maximal force against it via ramped isometric muscle contraction. Ramped isometric muscle contraction involved a 2‐second ramp up to MVC, 3‐second hold at MVC, followed by a 2‐second ramp down to resting, and a subsequent 30‐second rest period . The protocol for each MVC trial was consistent between participants: MVC trails started with the forearm extensor and flexor muscles, followed by the biceps, triceps, and trapezius muscles, alternating between the right and left sides of the body to prevent muscle fatigue.…”

“…Amplitude probability distribution function (APDF) curves were produced for each right and left muscle group using MATLAB software (The Mathworks, Inc) . Muscle activity patterns were used to identify the percentage of time each participant spent at or below a certain %MVC while performing PT and SS tasks with each of the three simulated surgical approaches . The 10th, 50th, and 90th percentiles represented the static, median, and peak load levels for muscle activity, respectively .…”

Normalizing shoulder EMG: An optimal set of maximum isometric voluntary contraction tests considering reproducibility

“…Prone V-thumbs up (Castelein et al, 2015) Prone Arm flexed and in line with lower trapezius muscle fibers. Scapular retraction with resistance applied on the upper part of the scapular spine.…”

“…A key factor to use EMG evaluations for rehabilitation or clinical trials is the ability to obtain reliable measurements over time. Previous studies on the normalization of the EMG signal of the shoulder have mainly focused on the tests leading to maximal activations (Boettcher et al, 2008;Castelein et al, 2015;Dal Maso et al, 2016;Ekstrom et al, 2005). To our knowledge, little has been done to evaluate the reproducibility of the normalization procedures.…”