Search results for "eccentric"

Validity of an inertial system for measuring velocity, force, and power during hamstring exercises performed on a flywheel resistance training device

2020

Background Inertial hamstring exercises promote functional changes leading to lower rates of hamstring injuries. However, variable training measurement systems have not been specifically validated for hamstring exercises. Accordingly, this study aimed to evaluate the validity of the Inertial Measurement System (IMS) to measure the velocity, force, and power during the performance of different hamstring exercises on a flywheel resistance training device. Methods Fifteen males (average age: 22.4 ± 2.5 years; body mass: 77.3 ± 9.8 kg; height: 179.5 ± 7.4 cm; weekly physical activity: 434.0 ± 169.2 min; years of strength training: 4.3 ± 2.2 years) performed the bilateral stiff-leg deadlift (SD…

Comparison of conventional hamstring/quadriceps ratio between genders in level-matched soccer players

2017

Abstract Objectives The main goal of our study is to compare the hamstring/quadriceps ( H / Q ) ratio at different knee angles between level-matched male and female soccer players and to determine whether differences in the H / Q ratio exist between the dominant and the non-dominant leg. Methods A cross-sectional study design was used to compare an isometric H / Q ratio and functional isokinetic ratio (between hamstring in eccentric contraction and quadriceps in concentric contraction) between males ( n  = 14) and females ( n  = 14). These ratios were studied at two different speeds of movement (60° s −1 and 180° s −1 ) and in five different positions (40°, 50°, 60°, 70° and 80° degrees of …

Electrical stimulation and swimming performance

1995

The purpose of the study was to examine the influence of a 3-wk period of electrostimulation training on the strength of the latissimus dorsi m. and the swimming performances of 14 competitive swimmers divided into 7 electrostimulated (EG) and 7 control swimmers (CG). The peak torques registered during the flexion-extension of the arm was determined with the help of an isokinetic dynamometer at different velocities (from -60 degrees.s(-1) to 360 degrees.s(-1)). Performances were measured over a 25-m pull buoy and a 50-m freestyle swim. For EG, a significant increase of the peak torques was measured in isometric, eccentric, and concentric conditions (P < 0.5). The swimming times declined sig…

Analysis of Compliance with Time under Tension and Force during Strengthening Exercises with Elastic Bands

2021

Quantifying training variables of a physical exercise modality is essential for an appropriate dosage. In training with elastic bands, time under tension (TUT) and force represent the duration and intensity of this force-training modality. The aims of this study were to evaluate the degree of compliance to TUT prescription for three different scenarios of two exercises and the comparison of the force values obtained versus the estimate values. A total of 29 healthy volunteers were evaluated in a clinical environment under controlled conditions in 3 different scenarios (different velocities or ROMs) of both shoulder abduction and knee extension in 2 sets of 10 repetitions per scenario within…

2018

Purpose: There is some controversy whether or not saccades change with age. This cross-sectional study aims to clarify the characteristics of reflexive saccades at various ages to establish a normative cohort in a standardized set-up. Second objective is to investigate the feasibility of saccadometry in daily ophthalmological practice. Methods: One hundred healthy participants aged between 6 and 76 years underwent an ophthalmologic examination and saccadometry, using an infrared video-oculography device, sampling at 220 Hz. The reflexive saccades were evoked in four directions and three target displacements each (5°/15°/30° horizontally and of 5°/10°/20° vertically). Saccadic peak velocity,…

Tensiomyography reliability and prediction of changes in muscle force following heavy eccentric strength exercise using muscle mechanical properties

2015

AbstractThe current study involved the completion of two distinct experiments. Experiment 1 analyzed the inter-day reliability of tensiomyography (TMG) muscle mechanical properties based on the amplitude of the muscle belly radial deformation, the time it takes to occur, and its velocity under maximal and submaximal stimuli, in the muscles rectus femoris, biceps femoris, and gastrocnemius lateralis, from 20 male sport students. Experiment 2 investigated whether changes in maximal voluntary isometric contraction (MVIC) could be predicted based on changes in TMG properties following 24 h after different squat training protocols (MS = multiple sets; DS = drop sets; EO = eccentric overload; FW …

Corrigendum to “Increased cross-education of muscle strength and reduced corticospinal inhibition following eccentric strength training” [Neuroscienc…

2015

Changes induced by eccentric training on force-velocity relationships of the elbow flexor muscles.

1995

The aim of this study was to examine the effects of a short term eccentric training period on force-velocity relationships of the elbow flexor muscles. From a muscle model, the maximal shortening velocity Vo(x) and the af parameter which varies according to the curvature of the force-velocity relationship of the muscle were determined. Sixteen volunteer subjects divided into 2 groups participated in this study (Group Eccentric GE, n = 8; Group Control GC, n = 8). The subjects performed, on an isokinetic ergometer, 2 maximal concentric elbow flexions at different angular velocities (60, 120, 180, 240, 300, 360 degrees s-1) and held maximal and submaximal isometric actions at an elbow flexion…

Greater Strength Gains after Training with Accentuated Eccentric than Traditional Isoinertial Loads in Already Strength-Trained Men

2016

As training experience increases it becomes more challenging to induce further neuromuscular adaptation. Consequently, strength trainers seek alternative training methods in order to further increase strength and muscle mass. One method is to utilize accentuated eccentric loading, which applies a greater external load during the eccentric phase of the lift as compared to the concentric phase. Based upon this practice, the purpose of this study was to determine the effects of 10 weeks of accentuated eccentric loading vs. traditional isoinertial resistance training in strength-trained men. Young (22 ± 3 years, 177 ± 6 cm, 76 ± 10 kg, n = 28) strength-trained men (2.6 ± 2.2 years experience) w…

C-Reactive Protein Is Elevated Only in High Creatine Kinase Responders to Muscle Damaging Exercise.

2019

The purpose of this study was to investigate if exertional rhabdomyolysis induced by an acute bout of plyometric exercise in untrained individuals was associated with histological characteristics of skeletal muscle, creatine kinase (CK) polymorphism or secondary damage. Twenty-six healthy male untrained individuals completed a bout of plyometric exercise (10 sets of 10 maximal squat jumps, with each standardized to achieve at least 95% of individual maximal jump height). Blood samples were taken, and perceived pain was scored immediately before the exercise intervention and 6 h, 1, 2, and 3 days post-intervention. Muscle biopsies were collected 9 or 4 days before (baseline) and 3 days after…