Search results for "Hamstring Muscles"
showing 9 items of 19 documents
Stability of pedalling mechanics during a prolonged cycling exercise performed at different cadences.
2005
The aim of this study was to analyse the effect of pedalling rate on the pattern of mechanical torque application and on neuromuscular fatigue during prolonged cycling exercise. Eleven well-trained individuals performed three 1-h pedalling sessions, at 50 rev.min-1, 110 rev.min-1 and a freely chosen cadence, at an intensity corresponding to 65% of their maximal aerobic power. The mechanical torque applied on the right pedal was recorded for 30 s every 5 min while pedalling. Contractile and neural properties of the quadriceps and hamstring muscles were analysed before and immediately after each of the three pedalling sessions. The post-exercise reduction in knee extensors maximal voluntary c…
The effects of the Nordic hamstring exercise on sprint performance and eccentric knee flexor strength: A systematic review and meta-analysis of inter…
2021
Objectives: The primary aim of this study was to investigate the effects of the Nordic hamstring exercise (NHE) on sprint performance (i.e., 5, 10 and 20 m) and explore associations between study characteristics and sprint outcomes in team sport players. Secondary aims were to (1) investigate the effects of the NHE on eccentric strength of the knee flexors (ESKF) with categorical subgroup analysis to determine differences between recreationally, well-trained individuals and young athletes, (2) determine the relation between ESKF and sprint performance in team sport players, and (3) explore the effect of study characteristics (i.e., weekly volume, time duration and body mass) on ESKF.Methods…
Injury prevention in male youth soccer: Current practices and perceptions of practitioners working at elite English academies
2017
Forty-one practitioners inclusive of physiotherapists, sports scientists and strength and conditioning coaches from the academies of elite soccer clubs in the United Kingdom completed an on-line questionnaire which examined their: (1) background information; (2) perceptions of injury occurrence and risk factors; (3) screening and return to play; and (4) approach to designing and delivering injury prevention programmes with a response rate of 55% (41/75). Contact injuries were the most common mechanism reported and players between 13-16 years of age were perceived to be at the greatest risk. Pertinent risk factors included: reduced lower limb and eccentric hamstring strength, proprioception,…
Comparison of Electromyographic Activity During Hip Extension Exercises Under Gravitational or Inertial Loading Conditions.
2021
Background: Hamstring injury prevention programs include strengthening, especially eccentric exercises using both gravitational and inertial loading. Inertial exercises are characterized by eccentric contractions of high intensity and velocity. This study aimed to analyze the muscular activation of the biceps femoris (BF), semitendinosus (ST), gluteus maximus (GM), and gracilis (GC) muscles during hip extension (HE) exercises performed under both gravitational and inertial loading conditions. Hypothesis: Inertial training would generate a greater activation of HE muscles than gravitational training. Study Design: Cross-sectional study. Level of Evidence: Level 4. Methods: Fifteen resistance…
Sex Differences in the Velocity of Muscle Contraction of the Hamstring and Quadriceps Among Recreationally Active Young Adults
2019
Martin-San Agustin, R, Medina-Mirapeix, F, Alakhdar, Y, and Benitez-Martinez, JC. Sex differences in the velocity of muscle contraction of the hamstring and quadriceps among recreationally active young adults. J Strength Cond Res 33(5): 1252-1257, 2019-This study determines sex differences in the velocity of contraction (VC) of 5 isolated muscles (biceps femoris, semitendinosus, rectus femoris, vastus medialis, and vastus lateralis) and in the relationships between them. Thirty-six female and 34 male recreationally active young adults participated in the study. The VC was measured by tensiomyography using normalized response velocity (Vrn) to perform comparisons. Sex comparisons were adjust…
Association between lower extremity muscle strength and acute ankle injury in youth team-sports athletes
2021
Abstract Objectives To investigate lower extremity muscle strength as risk factor for an acute ankle injury in youth athletes. Design Cohort study. Setting Basketball and floorball clubs. Participants 188 youth (≤21) male and 174 female athletes. Main outcome measures 1RM leg press, maximal concentric isokinetic quadriceps and hamstrings as well as maximal isometric hip abductor strength were measured and athletes were followed for an acute ankle injury up to three years. Cox regression models were used in statistical analyses. Results In males, greater 1RM leg press and maximal quadriceps strength increased the risk of any type of acute ankle injury (Hazard ratio [HR] for 1 SD increase, 1.…
Progressive active mobilization with dose control and training load in critically ill patients (PROMOB): Protocol for a randomized controlled trial
2020
The dose of progressive active mobilization is still uncertain. The purpose of this study is to identify if the addition of a protocol of progressive active mobilization with dose and training load control to usual care is effective in reducing the length of stay in intensive care unit (ICU) and the improvement of the functioning, incidence of ICU-acquired weakness (ICUAW), mechanical ventilation duration and mortality rate in patients hospitalized in ICU. It is Double-blind randomised clinical trial. The setting for this trial will be medical and surgical ICU of a university hospital. The study participants will be 118 patients aged> 18 years admitted to ICU for less than 72 hours. Partici…
Responsiveness of Electromyographically Assessed Skeletal Muscle Inactivity – methodological exploration and implications for health benefits
2022
Abstract Prolonged sedentary behaviour is detrimental to health due to low contractile activity in large lower extremity muscle groups. This muscle inactivity can be measured with electromyography (EMG), but it is unknown how methodological factors affect responsiveness longitudinally. This study aimed to rank 16 different EMG inactivity thresholds based on their responsiveness (absolute and standardized effect size, responsiveness) using data from a randomized controlled trial targeted at reducing and breaking up sedentary time (InPact, ISRCTN28668090). EMG inactivity duration and usual EMG inactivity bout duration (weighted median of bout lengths) were measured from large lower extremity …
Range of Motion and Injury Occurrence in Elite Spanish Soccer Academies. Not Only a Hamstring Shortening-Related Problem.
2020
Sanz, A, Pablos, C, Ballester, R, Sanchez-Alarcos, JV, and Huertas, F. Range of motion and injury occurrence in elite Spanish soccer academies. Not only a hamstring shortening-related problem. J Strength Cond Res 34(7): 1924-1932, 2020-Age-related development of range of motion (ROM) during an active hip flexion (active straight leg raise) and its relationship with hamstring injury occurrence were examined in 1657 young male soccer players (9-18 years of age). Age-related differences in ROM showed a significant decrease from U9 to U11 (p = 0.001), from U11 to U13 (p0.005), and from U9 to U13 (p0.001), whereas ROM increased from U13 to U15 and from U13 to U18 (both p's0.001). Interestingly, …