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Nunes H, Fernandes LG, Martins PN, Ferreira RM. The Effects of Nordic Hamstring Exercise on Performance and Injury in the Lower Extremities: An Umbrella Review. Healthcare (Basel) 2024; 12:1462. [PMID: 39120165 PMCID: PMC11311354 DOI: 10.3390/healthcare12151462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2024] [Revised: 07/17/2024] [Accepted: 07/21/2024] [Indexed: 08/10/2024] Open
Abstract
Due to their potential positive outcomes, hamstring eccentric exercises are becoming increasingly popular in training regimens. Among the various exercises, the Nordic Hamstring Exercise (NHE) is the most common. Despite its popularity, there are still some doubts about its benefits and risks. So, the aim of this umbrella review was to summarize the effects of NHE on performance and injury prevention. Following the PRISMA guidelines, a comprehensive literature search was conducted across multiple e-databases, according to the P (injured and non-injured athletes or recreationally active or healthy individuals) I (NHE) C (no intervention, placebo, or other interventions) O (performance or injury) S (systematic reviews) model. The quality of the studies was accessed with the AMSTAR-2. From the 916 systematic reviews found, only 10 could be included. They encompassed 125 studies, enrolling 17,260 subjects. The results from the studies indicate that NHE interventions demonstrated positive effects on sprint performance, muscle activation, eccentric strength, and muscle architecture (fascicle length, muscle thickness, and pennation angle). Furthermore, NHE is effective in preventing hamstring injuries (up to 51%). In conclusion, NHE should be integrated in training (especially, in the warm-up phase) for both enhancing athletic performance and preventing hamstring injuries. For achieving more positive results, it is recommended that high-volume is followed by low-volume maintenance, targeting 48 reps/week.
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Affiliation(s)
- Hugo Nunes
- Polytechnic Institute of Maia, N2i, Social Sciences, Education and Sports School, Avenida Carlos de Oliveira Campos, Castêlo da Maia, 4475-690 Maia, Portugal; (L.G.F.); (P.N.M.)
| | - Luís Gonçalves Fernandes
- Polytechnic Institute of Maia, N2i, Social Sciences, Education and Sports School, Avenida Carlos de Oliveira Campos, Castêlo da Maia, 4475-690 Maia, Portugal; (L.G.F.); (P.N.M.)
| | - Pedro Nunes Martins
- Polytechnic Institute of Maia, N2i, Social Sciences, Education and Sports School, Avenida Carlos de Oliveira Campos, Castêlo da Maia, 4475-690 Maia, Portugal; (L.G.F.); (P.N.M.)
| | - Ricardo Maia Ferreira
- Polytechnic Institute of Maia, N2i, Social Sciences, Education and Sports School, Avenida Carlos de Oliveira Campos, Castêlo da Maia, 4475-690 Maia, Portugal; (L.G.F.); (P.N.M.)
- Polytechnic Institute of Coimbra, Coimbra Health School, Scientific-Pedagogical Unit of Physiotherapy, Rua 5 de Outubro, São Martinho do Bispo, 3045-043 Coimbra, Portugal
- Sport Physical Activity and Health Research & Innovation Center (SPRINT), 4960-320 Melgaço, Portugal
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Alt T, Knicker AJ, Nodler YT, Strüder HK. Assisted or unassisted Nordic Hamstring Exercise? - Resistance exercise determinants at a glance. Sports Biomech 2024; 23:831-845. [PMID: 33726613 DOI: 10.1080/14763141.2021.1893376] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 02/16/2021] [Indexed: 10/21/2022]
Abstract
The Nordic Hamstring Exercise (NHE) effectively strengthens the knee flexors. Typically conducted without assistance, extended knee angles are not reached with sustained muscle activation in the presence of insufficient eccentric strength and/or fatigue. This might impair the desired neuromuscular adaptations and assessment accuracy. This study investigated kinetic and kinematic differences between assisted and unassisted NHEs (3 × 3 repetitions) performed by sixteen male sprinters (22 years, 181 cm, 76 kg). Kinetic (peak moment, impulse) and kinematic parameters (e.g., time under tension, range of motion to excessive downward acceleration (ROMDWA) were investigated. All analysed parameters significantly differed between assisted and unassisted NHEs (p ≤ 0.003; 0.635≤ ηp² ≤ 0.929) favouring assisted execution, except for peak moments and maximal hip flexion. Repetition 1 of assisted NHEs revealed 21% higher impulses rising to 82% during repetition 9. Equivalent interactions of mode and repetition became apparent for time under tension, ROMDWA, mean and fractional angular velocity. Unassisted NHEs elicited substantially greater inter-repetition fatigue (rep1 vs. rep9): +79% fractional angular velocity (d = 1.01), -41% impulse (d = 1.53), -31% ROMDWA (d = 0.99) and -29% time under tension (d = 1.45). Assisted NHEs ensured higher execution quality and lower between-participant variability by facilitating a controlled full-ROM movement. Three sets of 3 NHEs sufficed to induce substantial fatigue within and across sets.
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Affiliation(s)
- Tobias Alt
- Department of Biomechanics, Performance Analysis and Strength & Conditioning, Olympic Training and Testing Centre Westphalia, Dortmund, Germany
- Institute of Movement and Neuroscience, German Sport University, Cologne, Germany
| | - Axel J Knicker
- Institute of Movement and Neuroscience, German Sport University, Cologne, Germany
- Research Centre for Elite Sports, Momentum, Cologne, Germany
| | - Yannick T Nodler
- Institute of Movement and Neuroscience, German Sport University, Cologne, Germany
| | - Heiko K Strüder
- Institute of Movement and Neuroscience, German Sport University, Cologne, Germany
- Research Centre for Elite Sports, Momentum, Cologne, Germany
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de Keijzer KL, McErlain-Naylor SA, Beato M. Six Weeks of Unilateral Flywheel Hip-Extension and Leg-Curl Training Improves Flywheel Eccentric Peak Power but Does Not Enhance Hamstring Isokinetic or Isometric Strength. Int J Sports Physiol Perform 2024; 19:34-43. [PMID: 37917962 DOI: 10.1123/ijspp.2023-0035] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Revised: 08/12/2023] [Accepted: 09/12/2023] [Indexed: 11/04/2023]
Abstract
PURPOSE This preregistered trial investigated how 6 weeks of unilateral flywheel leg-curl and hip-extension training impact isokinetic, isometric, and flywheel strength and power outcomes. METHODS The study involved 11 male university athletes (age 22 [2] y; body mass 77.2 [11.3] kg; height 1.74 [0.09] m) with one leg randomly allocated to flywheel training and one leg to control. Unilateral eccentric and isometric knee-flexion torque and flywheel unilateral leg-curl and hip-extension peak power were tested. Training intensity and volume (3-4 sets of 6 + 2 repetitions) were progressively increased. RESULTS The intervention enhanced hip-extension concentric (P < .01, d = 1.76, large) and eccentric (P < .01, d = 1.33, large) peak power more than the control (significant interaction effect). Similarly, eccentric (P = .023, d = 1.05, moderate) peak power was enhanced for the leg curl. No statistically significant differences between conditions were found for isokinetic eccentric (P = .086, d = 0.77, moderate) and isometric (P = .431, d = 0.36, small) knee-flexor strength or leg-curl concentric peak power (P = .339, d = 0.52, small). Statistical parametric mapping analysis of torque-angle curves also revealed no significant (P > .05) time-limb interaction effect at any joint angle. CONCLUSION Unilateral flywheel hamstring training improved knee-flexor eccentric peak power during unilateral flywheel exercise but not flywheel concentric, isokinetic eccentric, or isometric (long-lever) knee-flexor strength.
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Affiliation(s)
- Kevin L de Keijzer
- School of Health and Sports Sciences, University of Suffolk, Ipswich, United Kingdom
- Institute of Health and Wellbeing, University of Suffolk, Ipswich, United Kingdom
| | - Stuart A McErlain-Naylor
- School of Health and Sports Sciences, University of Suffolk, Ipswich, United Kingdom
- Institute of Health and Wellbeing, University of Suffolk, Ipswich, United Kingdom
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, United Kingdom
| | - Marco Beato
- School of Health and Sports Sciences, University of Suffolk, Ipswich, United Kingdom
- Institute of Health and Wellbeing, University of Suffolk, Ipswich, United Kingdom
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Suskens JJM, Maas H, van Dieën JH, Kerkhoffs GMMJ, Goedhart EA, Tol JL, Reurink G. The Effect of the Nordic Hamstring Exercise on Muscle Activity: A Multichannel Electromyography Randomized Controlled Trial. J Appl Biomech 2023; 39:377-387. [PMID: 37567580 DOI: 10.1123/jab.2023-0037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 06/08/2023] [Accepted: 06/23/2023] [Indexed: 08/13/2023]
Abstract
The aim of this study was to evaluate the effect of a Nordic hamstring exercise intervention on biceps femoris long head, semitendinosus, and semimembranosus muscle's activity and relative contributions through multichannel electromyography. Twenty-four injury-free male basketball players (mean age 20 [3] y) were randomly assigned to a 12-week intervention (n = 13) or control group (n = 11). The primary outcome measures were normalized muscle activity (percentage of maximal voluntary isometric contraction, %MVIC) and relative contribution of hamstring muscles over 12 weeks. No effects were found on any of the primary outcome measures. Between-group differences over 12 weeks were 2.7%MVIC (95% confidence interval 95% CI, -0.7 to 6.1) for the biceps femoris long head, 3.4%MVIC (95% CI, -1.4 to 8.2) for the semitendinosus, and 0.8%MVIC (95% CI, -3.0 to 4.6) for the semimembranosus, P = .366. Between-group differences over 12 weeks were 1.0% relative contribution (%con; 95% CI, -3.0 to 5.1) for the biceps femoris long head, 2.2% relative contribution (95% CI, -2.8 to 7.2) for the semitendinosus, and -3.3% relative contribution (95% CI, -6.4 to -0.1) for the semimembranosus P = .258. A positive value implies a higher value for the Nordic group. A Nordic hamstring exercise intervention did not affect the level of muscle activity and relative contribution of hamstring muscles in performance of the Nordic hamstring exercise.
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Affiliation(s)
- Jozef J M Suskens
- Department of Orthopedic Surgery and Sports Medicine, Amsterdam UMC location University of Amsterdam, Amsterdam,The Netherlands
- Amsterdam Movement Sciences, Sports, Amsterdam,The Netherlands
- Amsterdam Collaboration on Health & Safety in Sports (ACHSS), AMC/VUmc IOC Research Center, Amsterdam,The Netherlands
| | - Huub Maas
- Amsterdam Movement Sciences, Sports, Amsterdam,The Netherlands
- Department of Human Movement Sciences, Faculty of Behavioral and Movement Sciences, Amsterdam Movement Sciences (AMS), Vrije Universiteit, Amsterdam,The Netherlands
| | - Jaap H van Dieën
- Amsterdam Movement Sciences, Sports, Amsterdam,The Netherlands
- Department of Human Movement Sciences, Faculty of Behavioral and Movement Sciences, Amsterdam Movement Sciences (AMS), Vrije Universiteit, Amsterdam,The Netherlands
| | - Gino M M J Kerkhoffs
- Department of Orthopedic Surgery and Sports Medicine, Amsterdam UMC location University of Amsterdam, Amsterdam,The Netherlands
- Amsterdam Movement Sciences, Sports, Amsterdam,The Netherlands
- Amsterdam Collaboration on Health & Safety in Sports (ACHSS), AMC/VUmc IOC Research Center, Amsterdam,The Netherlands
| | - Edwin A Goedhart
- FIFA Medical Center, Royal Netherlands Football Association, Zeist,The Netherlands
| | - Johannes L Tol
- Amsterdam Movement Sciences, Sports, Amsterdam,The Netherlands
- Amsterdam Collaboration on Health & Safety in Sports (ACHSS), AMC/VUmc IOC Research Center, Amsterdam,The Netherlands
- Aspetar Orthopedic and Sports Medicine Hospital, Doha,Qatar
| | - Gustaaf Reurink
- Amsterdam Movement Sciences, Sports, Amsterdam,The Netherlands
- Amsterdam Collaboration on Health & Safety in Sports (ACHSS), AMC/VUmc IOC Research Center, Amsterdam,The Netherlands
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Chen J, Wu T, Guo Y. Nordic hamstring exercises in functional knee rehabilitation after anterior cruciate ligament reconstruction: a prospective, randomised, controlled study. Sci Rep 2023; 13:19039. [PMID: 37923738 PMCID: PMC10624851 DOI: 10.1038/s41598-023-45817-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 10/24/2023] [Indexed: 11/06/2023] Open
Abstract
To study the effect of using Nordic hamstring exercise method on muscle strength and knee joint stability of patients after ACL reconstruction. 60 patients admitted to our hospital for ACL reconstruction were randomly divided into a test group (n = 30, applying Nordic hamstring exercise) and a control group (n = 30, applying conventional rehabilitation training methods), and the difference in the circumference of the thighs of the patients in the two groups was analysed after training, and the peak torque (PT), total torque (PT), and flexion and extension strength were measured by using the Biodex system3 Multi-joint Isokinetic Testing System at knee joints with an angular velocity of 60°/s and 120°/s. The peak torque (PT), total work (TW), and average peak torque (AVG PT) were measured by extension and flexion strength at angular velocity, and the Lysholm Knee Score was used to assess the knee function of 60 patients. There was no difference in the difference in thigh circumference between the two groups before surgery (P > 0.05); the difference in thigh circumference between the patients in the test group at 12 and 24 weeks after surgery was (- 0.35 ± 0.22) cm and (0.12 ± 0.03) cm, respectively, which were higher than those in the control group, (- 0.51 ± 0.15) cm and (- 0.41 ± 0.34) cm (P < 0.05). At the 12th and 24th postoperative weeks, the popliteal muscle strength of both groups was improved compared with that before surgery; among them, by comparing the popliteal peak moments with different angular velocities, the ratio of popliteal peak moment on the affected side/peak moment on the healthy side of the popliteal muscle of the experimental group was significantly higher than that of the control group, and the difference was significant (P < 0.05), but there was still a gap compared with that of the healthy side. The Lachmen test and the anterior drawer test were negative in the test and control groups at the 24th postoperative week of review, and the anterior tibial shift was < 5 mm in the KT-1000 test, and the difference in the anterior shift was < 3 mm compared with the healthy side, and there was no significant difference between the two groups. By Nordic hamstring exercise can make patients after knee ACL reconstruction reduce patient pain, accelerate the recovery of knee function, improve the swelling of the lower limb, reach the level of flexor strength of the healthy side within 24 weeks, and can increase the stability of the knee joint.
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Affiliation(s)
- JiaWei Chen
- Hunan Mechanical Electrical Polytechnic, Changsha, 410000, Hunan, China
| | - TianYu Wu
- Beijing Sport University, Beijing, 100010, China.
- The People's Liberation Army Joint Logistic Support Force Sanya Rehabilitation and Recuperation Center, Sanya, 572000, Hainan, China.
| | - Ying Guo
- Qiongzhong People's Hospital of Li and Miao Autonomous Country, Qiongzhong County, 572923, Hainan, China
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Alt T, Knicker AJ, Nodler YT, Strüder HK. What Are We Aiming for in Eccentric Hamstring Training: Angle-Specific Control or Supramaximal Stimulus? J Sport Rehabil 2023; 32:782-789. [PMID: 37339771 DOI: 10.1123/jsr.2022-0372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 03/18/2023] [Accepted: 04/24/2023] [Indexed: 06/22/2023]
Abstract
CONTEXT Different resistance exercise determinants modulate the musculotendinous adaptations following eccentric hamstring training. The Nordic Hamstring Exercise (NHE) can be performed 2-fold: the movement velocity irreversibly increases toward the end of the range of motion or it is kept constant. DESIGN This cross-sectional study aimed to investigate if the downward acceleration angle (DWAangle) can be used as a classification parameter to distinguish between increasing and constant velocity NHE execution. Furthermore, the kinetic and kinematic differences of these 2 NHE execution conditions were examined by analyzing the DWAangle in relation to the angle of peak moment. METHODS A total of 613 unassisted NHE repetitions of 12 trained male sprinters (22 y, 181 cm, 76 kg) were analyzed. RESULTS The majority of analyzed parameters demonstrated large effects. NHEs with constant velocity (n = 285) revealed significantly higher impulses (P < .001; d = 2.34; + 61%) and fractional time under tension (P < .001; d = 1.29; +143%). Although the generated peak moments were significantly higher for constant velocity (P = .003; d = 0.29; +4%), they emerged at similar knee flexion angles (P = .167; d = 0.28) and revealed on average just low relationships to the DWAangle (Rmean2=22.4%). DWAangle highly correlated with the impulse (Rmean2=60.8%) and δ (DWAangle-angle of peak moment; Rmean2=83.6%). CONCLUSIONS Relating DWAangle to angle of peak moment assists to distinguish between significantly different NHE execution, which will potentially elicit different musculotendinous adaptations. These insights are essential for coaches and athletes to understand how to manipulate eccentric hamstring training to change its purpose.
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Affiliation(s)
- Tobias Alt
- Department of Biomechanics, Performance Analysis and Strength & Conditioning, Olympic Training and Testing Center Westphalia, Dortmund,Germany
- Institute of Movement and Neuroscience, German Sport University, Cologne,Germany
| | - Axel J Knicker
- Institute of Movement and Neuroscience, German Sport University, Cologne,Germany
- Research Center for Elite Sports (momentum),Cologne,Germany
| | - Yannick T Nodler
- Institute of Movement and Neuroscience, German Sport University, Cologne,Germany
| | - Heiko K Strüder
- Institute of Movement and Neuroscience, German Sport University, Cologne,Germany
- Research Center for Elite Sports (momentum),Cologne,Germany
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Soga T, Yamaguchi S, Inami T, Saito H, Hakariya N, Nakaichi N, Shinohara S, Akiyama K, Hirose N. The Validity and Reliability of a Smartphone Application for Break-Point Angle Measurement during Nordic Hamstring Exercise. Int J Sports Phys Ther 2023; 18:917-922. [PMID: 37547835 PMCID: PMC10399091 DOI: 10.26603/001c.83936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Accepted: 05/24/2023] [Indexed: 08/08/2023] Open
Abstract
Background A recently developed smartphone application (Nordic Angle) allows the automatic calculation of the break-point angle (BPA) during Nordic hamstring exercise (NHE) without transferring the collected data to a computer. The BPA is the point at which the hamstrings are unable to withstand force. However, the validity of the BPA values obtained by this method has not been examined. Hypothesis/Purpose This study aimed to evaluate the validity and reliability of the Nordic Angle by comparing the BPA values of the Nordic Angle with those of two-dimensional motion analysis software that can calculate the angles and angular velocities of various joints. Study Design Cohort assessing Validity and Reliability. Methods The validity of the Nordic Angle BPA data was verified by Spearman's correlation test for consistency with the movement analysis data, and the magnitude of the correlation was indicated by rs. The agreement between these measurements was examined using the Bland-Altman analysis. The reliability of the Nordic Angle and motion analysis was examined using the intraclass correlation coefficient (ICC) (1,k) based on data from repeated trials within a day. Results Although the spearman correlation between the Nordic angle and the angle determined using motion analysis did not reach statistical significance (p = 0.052), a very large correlation was present (rs = 0.75). The difference between the mean values of the Nordic Angle and motion analysis was 0.4 ± 2.1°, and the limits of agreement ranged from -3.9° to 4.6°. In two BPA measurements, the Nordic Angle showed perfect reliability (ICC = 1.00, p < 0.001), while motion analysis showed nearly perfect reliability (ICC = 0.97, p < 0.001). Conclusion The Nordic Angle, which has both validity and reliability, may be appropriate for field measurement because it allows immediate feedback of BPA and the measurement of many athletes. Level of evidence 3b©The Author(s).
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Affiliation(s)
| | | | | | - Hiromi Saito
- Graduate School of Sport Sciences Waseda University
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Alt T, Roos T, Nolte K, Modenbach D, Knicker AJ, Jaitner T. Modulating the Nordic Hamstring Exercise From "Zero to Hero": A Stepwise Progression Explored in a High-Performance Athlete. J Athl Train 2023; 58:329-337. [PMID: 35984720 PMCID: PMC11215643 DOI: 10.4085/1062-6050-0010.22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND The Nordic hamstring exercise (NHE) is commonly implemented to selectively improve eccentric knee-flexor strength. However, the standard version of the exercise (leveled shanks, extended hip joint) is too strenuous for most individuals, whose muscle activity rapidly decreases at extended knee angles. Hitherto, a gradual approach to the exercise has been missing. In this exploratory case study, we investigated elite performance to introduce a stepwise progression to the NHE. OBJECTIVE To determine the extent to which exercise modifications (shank inclination, additional load, hip flexion) altered NHE mechanics. DATA COLLECTION AND ANALYSIS One male long jumper (age = 33 years, height = 171 cm, mass = 69 kg) with high-level expertise in the NHE performed 20 exercise variations. The corresponding kinematics, kinetics, and electromyographic activity of the biceps femoris long head (BFlh) and semitendinosus (ST) muscles were evaluated. RESULTS Exercise variations demonstrated gradually increased peak moments from 69% (zigzag pose) to 154% (inclined bent single-legged version) versus a standard NHE. Shank inclination and additional load elicited small to moderate effects on peak moments, BFlh, and ST (0.24 ≤ d ≤ 0.72), whereas hip flexion largely affected all tested variables (2.80 ≤ d ≤ 6.66), especially muscle activity (BFlh = -63%; ST = -55% of maximal voluntary isometric contraction). COMMENTARY These insights will help practitioners and scientists design multifaceted stepwise NHE progressions by creating differentiated stimuli that best match the strength capacities of individuals and address their specific needs.
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Affiliation(s)
- Tobias Alt
- Department of Biomechanics, Performance Analysis and Strength & Conditioning, Olympic Training and Testing Centre Westphalia, Dortmund, Germany
| | - Tilman Roos
- Institute of Sport Science, Otto-von-Guericke University, Magdeburg, Germany
| | - Kevin Nolte
- Department for Sport and Sport Science, TU Dortmund University, Germany
| | - Dominik Modenbach
- Department for Sport and Sport Science, TU Dortmund University, Germany
| | - Axel J. Knicker
- Institute of Movement & Neuroscience, German Sport University, Cologne
- Research Centre of Elite Sport (Momentum), Cologne, Germany
| | - Thomas Jaitner
- Department for Sport and Sport Science, TU Dortmund University, Germany
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Moran J, Vali N, Drury B, Hammami R, Tallent J, Chaabene H, Ramirez-Campillo R. The effect of volume equated 1- versus 2-day formats of Nordic hamstring exercise training on fitness in youth soccer players: A randomised controlled trial. PLoS One 2022; 17:e0277437. [PMID: 36580466 PMCID: PMC9799302 DOI: 10.1371/journal.pone.0277437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 10/27/2022] [Indexed: 12/30/2022] Open
Abstract
PURPOSE This randomised controlled trial examined the effect of an 8-week volume-equated programme of Nordic hamstring exercise (NHE) training, executed at frequencies of 1- or 2-days per week, on fitness (10 m and 40 m sprint, '505' change of direction [COD] and standing long jump [SLJ]) in male youth soccer players (mean age: 16.4 ± 0.81 years). METHOD Players were divided into an experimental group (n = 16) which was further subdivided into 1-day (n = 8) and 2-day (n = 8) per week training groups and a control group (n = 8). RESULTS There were significant group-by-time interactions for 10-m sprint (p<0.001, η2 = 0.120, d = 2.05 [0.57 to 3.53]), 40-m sprint (p = 0.001, η2 = 0.041, d = 1.09 [-0.23 to 2.4]) and COD (p = 0.002, η2 = 0.063, d = 1.25 [-0.09 to 2.59). The experimental group demonstrated a 'very large' effect size (d = 3.02 [1.5 to 4.54]) in 10-m sprint, and 'large' effect sizes in 40-m sprint (d = 1.94 [0.98 to 2.90]) and COD (d = 1.84 [0.85 to 2.83). The control group showed no significant changes. There were no significant differences between the 1-day and 2-day training groups. In three of the four tests (40 m, COD, SLJ) the 2-day group demonstrated larger effect sizes. Ratings of perceived exertion (RPE) were significantly lower in the 2-day group (p<0.001, 3.46 [1.83 to 5.04). CONCLUSION The NHE increases fitness in youth soccer players and there may be advantages to spreading training over two days instead of one.
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Affiliation(s)
- Jason Moran
- School of Sport, Rehabilitation, and Exercise Sciences, University of Essex, Colchester, United Kingdom
- * E-mail:
| | - Norodin Vali
- Department of Exercise Physiology, Shahid Rajaee Teacher Training University, Tehran, Iran
| | - Ben Drury
- Department of Sport, Hartpury University, Gloucestershire, United Kingdom
| | - Raouf Hammami
- Higher Institute of Sport and Physical Education of Ksar-Said, Universite de La Manouba, Tunis, Tunisia
- Research Laboratory: Education, Motor Skills, Sports and Health, Higher Institute of Sport and Physical Education of Sfax, University of Sfax, Sfax, Tunisia
| | - Jamie Tallent
- School of Sport, Rehabilitation, and Exercise Sciences, University of Essex, Colchester, United Kingdom
| | - Helmi Chaabene
- Department of Sports and Health Sciences, Faculty of Human Sciences, University of Potsdam, Potsdam, Germany
- Higher Institute of Sports and Physical Education, Kef, University of Jendouba, Jendouba, Tunisia
| | - Rodrigo Ramirez-Campillo
- Exercise and Rehabilitation Sciences Laboratory, Faculty of Rehabilitation Sciences, School of Physical Therapy, Universidad Andres Bello, Santiago, Chile
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Abdelkader M, Hammami R, Drury B, Clark N, Sandercock G, Shaw I, Shaw BS, Chortane SG, Moran J. A randomised controlled trial of 1- versus 2-day per week formats of Nordic hamstring training on explosive athletic tasks in prepubertal soccer players. J Sports Sci 2022; 40:2173-2181. [PMID: 36383389 DOI: 10.1080/02640414.2022.2145737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
This randomised controlled trial examined the effect of volume-equated programmes of Nordic hamstring exercise (NHE) training, executed at frequencies of 1- or 2-days per week, on explosive athletic tasks (30 m sprint, 15 m manoeuvrability and standing long jump [SLJ]) in male youth soccer players (mean age: 10.3 ± 0.5 years). Players were divided into an experimental group (n = 31) which was further subdivided into 1-day (n = 16) and 2-days (n = 15) per week training conditions, and a control group (n = 14). There were significant group-by-time interactions for 30-m sprint (p < 0.001, d = 0.6), SLJ (p = 0.001, d = 1.27) and 15 m manoeuvrability (p < 0.001, d = 0.61). The experimental group demonstrated small to moderate effect sizes in 30-m sprint (d = 0.42, p = 0.077), SLJ (d = 0.97, p < 0.001) and 15 m manoeuvrability (d = 0.61, p < 0.001). The control group showed small significant performance decrements or no change in these variables. There were no significant differences between the 1-day and 2-day training groups. In two of the three tests (30 m sprint, SLJ) the 2-day group demonstrated larger effect sizes. The NHE enhances explosive athletic task performance in prepubertal youth soccer players and there may be only small advantages to spreading training over two days instead of one.
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Affiliation(s)
- Mahmoudi Abdelkader
- Research Unit Sports Performance, Health and Society, Higher Institute of Sport and Physical Education of Ksar-Said, Universite de La Manouba, Tunis, Tunisia
| | - Raouf Hammami
- Research Unit Sports Performance, Health and Society, Higher Institute of Sport and Physical Education of Ksar-Said, Universite de La Manouba, Tunis, Tunisia.,Research Laboratory: Education, Motor Skills, Sports and Health (EM2S, UR15JS01), Higher Institute of Sport and Physical Education of Sfax, University of Sfax, Sfax, Tunisia
| | - Ben Drury
- Department of Sport, Hartpury University, Gloucestershire, UK
| | - Nicholas Clark
- School of Sport, Rehabilitation, and Exercise Sciences, University of Essex, Colchester, UK
| | - Gavin Sandercock
- School of Sport, Rehabilitation, and Exercise Sciences, University of Essex, Colchester, UK
| | - Ina Shaw
- School of Sport, Rehabilitation, and Exercise Sciences, University of Essex, Colchester, UK
| | - Brandon S Shaw
- School of Sport, Rehabilitation, and Exercise Sciences, University of Essex, Colchester, UK
| | - Sabri Gaied Chortane
- Research Unit Sports Performance, Health and Society, Higher Institute of Sport and Physical Education of Ksar-Said, Universite de La Manouba, Tunis, Tunisia
| | - Jason Moran
- School of Sport, Rehabilitation, and Exercise Sciences, University of Essex, Colchester, UK
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11
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Alt T, Severin J, Schmidt M. Quo Vadis Nordic Hamstring Exercise-Related Research?-A Scoping Review Revealing the Need for Improved Methodology and Reporting. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:11225. [PMID: 36141503 PMCID: PMC9517005 DOI: 10.3390/ijerph191811225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 08/31/2022] [Accepted: 09/02/2022] [Indexed: 06/16/2023]
Abstract
The objective of this scoping review is to assess Nordic Hamstring Exercise quality (ANHEQ) of assessments and interventions according to the ANHEQ rating scales and to present practical recommendations for the expedient design and reporting of future studies. A total of 71 Nordic Hamstring Exercise (NHE) assessments and 83 NHE interventions were selected from the data sources PubMed, Scopus, and SPORTDiscus. Research studies which were presented in peer-reviewed academic journals and implemented the NHE during laboratory-based assessments or multi-week interventions met the eligibility criteria. NHE assessments analyzed force (51%), muscle activation (41%), knee angle kinematics (38%), and bilateral symmetry (37%). NHE interventions lasted 4-8 weeks (56%) and implied an exercise volume of two sessions per week (66%) with two sets per session (41%) and ≥8 repetitions per set (39%). The total ANHEQ scores of the included NHE assessments and interventions were 5.0 ± 2.0 and 2.0 ± 2.0 (median ± interquartile range), respectively. The largest deficits became apparent for consequences of impaired technique (87% 0-point-scores for assessments) and kneeling height (94% 0-point-scores for interventions). The 0-point-scores were generally higher for interventions compared to assessments for rigid fixation (87% vs. 34%), knee position (83% vs. 48%), kneeling height (94% vs. 63%), and separate familiarization (75% vs. 61%). The single ANHEQ criteria, which received the highest score most frequently, were rigid fixation (66% of assessments) and compliance (33% of interventions). The quality of NHE assessments and interventions was generally 'below average' or rather 'poor'. Both NHE assessments and interventions suffered from imprecise reporting or lacking information regarding NHE execution modalities and subsequent analyses. Based on the findings, this scoping review aggregates practical guidelines how to improve the design and reporting of future NHE-related research.
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Affiliation(s)
- Tobias Alt
- Department of Biomechanics, Performance Analysis and Strength & Conditioning, Olympic Training and Testing Centre Westphalia, 44139 Dortmund, Germany
| | - Jannik Severin
- Institute of Movement and Neuroscience, German Sport University, 50933 Cologne, Germany
| | - Marcus Schmidt
- Institute for Sport and Sport Science, TU Dortmund University, 44227 Dortmund, Germany
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Widodo AF, Tien CW, Chen CW, Lai SC. Isotonic and Isometric Exercise Interventions Improve the Hamstring Muscles’ Strength and Flexibility: A Narrative Review. Healthcare (Basel) 2022; 10:healthcare10050811. [PMID: 35627948 PMCID: PMC9140507 DOI: 10.3390/healthcare10050811] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 04/23/2022] [Accepted: 04/24/2022] [Indexed: 02/01/2023] Open
Abstract
Background: Hamstring weakness has been associated with an increased risk of hamstring strain, a common sports injury that occurs when athletes perform actions such as quick sprints. The hamstring complex comprises three distinct muscles: the long and short heads of the bicep femoris, the semimembranosus, and the semitendinosus. Methods: The researchers collected the data from different electronic databases: PubMed, Google Scholar, and the Web of Science. Results: Many studies have been conducted on the numerous benefits of hamstring strength, in terms of athletic performance and injury prevention. Isotonic and isometric exercises are commonly used to improve hamstring strength, with each exercise type having a unique effect on the hamstring muscles. Isotonic exercise improves the muscles’ strength, increasing their ability to resist any force, while isometric training increases strength and the muscles’ ability to produce power by changing the muscle length. Conclusions: These exercises, when performed at low intensity, but with high repetition, can be used by the healthy general population to prepare for training and daily exercise. This can improve hamstring muscle strength and flexibility, leading to enhanced performance and reduced injury risk.
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Affiliation(s)
- Akhmad Fajri Widodo
- International Sport Science Master’s Program, College of Human Development and Health, National Taipei University of Nursing and Health Sciences, Taipei 112303, Taiwan;
| | - Cheng-Wen Tien
- Physical Education Office, General Education Centre, National Taipei University of Nursing and Health Sciences, Taipei 112303, Taiwan;
| | - Chien-Wei Chen
- International Sport Science Master’s Program, College of Human Development and Health, National Taipei University of Nursing and Health Sciences, Taipei 112303, Taiwan;
- Department of Exercise and Health Science, College of Human Development and Health, National Taipei University of Nursing and Health Sciences, Taipei 112303, Taiwan;
- Correspondence:
| | - Shih-Chiung Lai
- Department of Exercise and Health Science, College of Human Development and Health, National Taipei University of Nursing and Health Sciences, Taipei 112303, Taiwan;
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13
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Vicente-Mampel J, Bautista IJ, Martín F, Maroto-Izquierdo S, Van Hooren B, Baraja-Vegas L. Effects of ankle position during the Nordic Hamstring exercise on range of motion, heel contact force and hamstring muscle activation. Sports Biomech 2022:1-13. [PMID: 35045792 DOI: 10.1080/14763141.2021.2025416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 12/30/2021] [Indexed: 10/19/2022]
Abstract
One of the main benefits of the Nordic Hamstring Exercise (NHE) is that it can be performed without the need of any extra material. However, numerous technical execution variables such as the ankle and pelvis position can influence the performance. The primary aims of this study were to investigate the effects of ankle position (i.e., plantar or dorsal flexion) on Nordic Hamstring Break Point (NHBP), repetition time and heel contact force. A secondary aim was to investigate differences in biceps femoris long head and semitendinosus muscle activation. Male professional field hockey players (n = 12) volunteered for the study. Paired t-tests were used to analyse the effect of ankle position on muscle NHBP, eccentric peak torque and repetition time. Ankle dorsal flexion resulted in a higher NHBP (p = 0.002, effect size [ES] = 1.48 [0.57 to 2.38]), repetition time (p = 0.004, ES = 0.98 [0.24 to 1.72]) and both absolute and relative heel contact force (p = 0.028, ES = 0.67 [0.01 to 1.34], p = 0.017, ES = 0.76 [0.07 to 1.44], respectively) compared to plantar flexion. Muscle activation was not significant different. This study showed a higher NHBP, absolute and relative heel contact force and repetition time with a dorsal flexed ankle vs. a plantar flexed ankle in the NHE, without changes in hamstrings muscle activation.
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Affiliation(s)
- Juan Vicente-Mampel
- Department of Physiotherapy, Catholic University of Valencia, Torrent, Spain
| | - Iker J Bautista
- Department of Physiotherapy, Catholic University of Valencia, Torrent, Spain
| | - Fernando Martín
- Research Group in Prevention and Health in Exercise and Sport, University of Valencia, Valencia, Spain
| | | | - Bas Van Hooren
- Department of Nutrition and Movement Sciences, Nutrim School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Luis Baraja-Vegas
- Department of Physiotherapy, Catholic University of Valencia, Torrent, Spain
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14
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Alt T, Schmidt M. The ANHEQ Evaluation Criteria: Introducing Reliable Rating Scales for Assessing Nordic Hamstring Exercise Quality. SPORTS MEDICINE - OPEN 2021; 7:91. [PMID: 34894312 PMCID: PMC8665968 DOI: 10.1186/s40798-021-00383-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 11/18/2021] [Indexed: 11/10/2022]
Abstract
BACKGROUND The Nordic Hamstring Exercise (NHE) is very popular for selective eccentric hamstring strengthening. However, NHE-related research is hindered by insufficient details about implementation and reporting. Available tools to assess study quality (e.g., PEDro or TESTEX scale) are too unspecific to account for the specific demands of NHE. Therefore, this study aimed to introduce two rating scales for Assessing Nordic Hamstring Exercise Quality (ANHEQ) of assessment and intervention studies. METHODS Eighteen graduated sports scientists, sports physiotherapists and elite coaches with scientific experience independently evaluated the quality of published NHE studies via ANHEQ scales, each comprising eight items and a maximal 13-point score. Inter-rater agreement was analyzed by using criterion-based reference values, while Krippendorff´s alpha determined inter-rater reliability. Systematic differences of the summated ANHEQ scores were determined using Friedman tests. RESULTS Inter-rater agreement was 87 ± 5% for NHE assessments and 88 ± 6% for interventions with single items ranging from 71 to 100%. Alpha values for inter-rater reliability ranged from fair (.250) to perfect (1.00) depending on the item. Total ANHEQ scores revealed coefficients of .829 (almost perfect) and .772 (substantial) without significant inter-rater differences (p = .292). CONCLUSIONS The ANHEQ scales are suitable tools to rate NHE execution quality and data presentation. They facilitate a comprehensive review of NHE-related evidence and potentially improve the design and reporting of future NHE studies.
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Affiliation(s)
- Tobias Alt
- Department of Biomechanics, Performance Analysis and Strength and Conditioning, Olympic Training and Testing Centre Westphalia, Dortmund, Germany
| | - Marcus Schmidt
- Department for Sports and Sport Sciences, TU Dortmund University, Dortmund, Germany.
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15
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Whyte EF, Heneghan B, Feely K, Moran KA, O'Connor S. The Effect of Hip Extension and Nordic Hamstring Exercise Protocols on Hamstring Strength: A Randomized Controlled Trial. J Strength Cond Res 2021; 35:2682-2689. [PMID: 31356512 DOI: 10.1519/jsc.0000000000003220] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
ABSTRACT Whyte, EF, Heneghan, B, Feely, K, Moran, KA, and O'Connor, S. The effect of hip extension and Nordic hamstring exercise protocols on hamstring strength: A randomized controlled trial. J Strength Cond Res 35(10): 2682-2689, 2021-Lower and between-limb asymmetrical eccentric hamstring isokinetic strength may be associated with hamstring injuries, which mainly affect the biceps femoris. The 45° hip extension exercise (HEE) strengthens the hamstrings in the lengthened position where the biceps femoris experiences greatest loading during high-speed running. However, the effect of an HEE program on eccentric hamstring isokinetic strength has not been investigated or compared with the Nordic Hamstring Exercise (NHE) program. Twenty-four male, varsity, Gaelic footballers (22.4 ± 2.7 years; 182.1 ± 6.0 cm; 84.4 ± 7.9 kg) were randomly allocated to an HEE or NHE 4-week program. Isokinetic (60°·s-1) eccentric peak torque, functional hamstring-to-quadriceps ratio, and between-limb eccentric strength (absolute and percentage) asymmetries were recorded before and after intervention. Muscle soreness scores were reported after exercise using a visual analogue scale. A mixed between-within analysis of variance investigated group (HEE vs. NHE) by time (pre vs. post) interaction effects, and any main effects. An independent-samples t-test compared muscle soreness scores between the NHE and HEE groups. No interaction or group main effects were found. Main effects for time were observed on dominant and nondominant limbs for eccentric peak torque (p < 0.001, η2 = 0.21, p = 0.01, η2 = 0.51, respectively) and functional hamstring quadriceps ratio (p = 0.03, η2 = 0.59, p < 0.0001, η2 = 0.26, respectively). There were no main effects for time between-limb eccentric peak torque or percentage asymmetries (p = 0.41, η2 = 0.03, p = 0.20, η2 = 0.07, respectively), or differences in muscle soreness scores (p > 0.05). A 4-week HEE program increases eccentric hamstring isokinetic strength similar to a NHE program, which may be useful as part of a hamstring injury prevention program.
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Affiliation(s)
- Enda F Whyte
- School of Health and Human Performance, Dublin City University, Collins Avenue, Glasnevin, Dublin, Ireland
| | - Brian Heneghan
- School of Health and Human Performance, Dublin City University, Collins Avenue, Glasnevin, Dublin, Ireland
| | - Kevin Feely
- School of Health and Human Performance, Dublin City University, Collins Avenue, Glasnevin, Dublin, Ireland
- Kevin Feely Athletic Therapy, Dublin, Ireland ; and
| | - Kieran A Moran
- School of Health and Human Performance, Dublin City University, Collins Avenue, Glasnevin, Dublin, Ireland
- Insight Center for Data Analytics, Dublin City University, Dublin, Ireland
| | - Siobhán O'Connor
- School of Health and Human Performance, Dublin City University, Collins Avenue, Glasnevin, Dublin, Ireland
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16
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Sconce E, Heller B, Maden-Wilkinson T, Hamilton N. Agreement between methods and terminology used to assess the kinematics of the Nordic hamstring exercise. J Sports Sci 2021; 39:2859-2868. [PMID: 34459716 DOI: 10.1080/02640414.2021.1968127] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The Nordic hamstring exercise (NHE) is employed as a component of preventative training programmes to minimise hamstring strain injury risk. Variation in the methods and terminology used to assess the NHE makes comparison between studies difficult. We aimed to compare the utility of kinetic and kinematic metrics by comparing several collected concurrently. 18 male recreational rugby union participants completed 3 bilateral NHE repetitions on a hamstring device equipped with in-line strain gauge load cells, integrated with a 3-dimensional motion tracking system. Mean break-point angle occurred after the angle at first acceleration (121.5 ± 10.4° vs. 119.2 ± 7.1°) whereas break-torque angle (BTA) occurred later in the NHE action (126.0 ± 9.8°) showing highest correlation to the angle at greatest acceleration (123.9 ± 7.9°, r = 0.85). Future research should consider movement quality as the angular velocity of the knee joint at BTA demonstrated large variation (range = 3.6-93.4 deg·s1), with high intrasubject variability of relative trunk-to-thigh angle at peak-torque (range = 0.4-44.7°). This study proposes standardisation of methods and terminology used to define the NHE. Measuring BTA is recommended to represent the point at which hamstring muscle failure occurs, specific to the proposed injury mechanism during high-speed running.
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Affiliation(s)
- Emma Sconce
- Sports Engineering Research Group (SERG), Advanced Wellbeing Research Centre (AWRC), Sheffield Hallam University, Sheffield, South Yorkshire, UK
| | - Ben Heller
- Sports Engineering Research Group (SERG), Advanced Wellbeing Research Centre (AWRC), Sheffield Hallam University, Sheffield, South Yorkshire, UK
| | - Tom Maden-Wilkinson
- Physical Activity, Wellness and Public Health Research Group (PAWPH, Advanced Wellbeing Research Centre (AWRC), Sheffield, South Yorkshire, UK
| | - Nick Hamilton
- Sports Engineering Research Group (SERG), Advanced Wellbeing Research Centre (AWRC), Sheffield Hallam University, Sheffield, South Yorkshire, UK
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17
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Afonso J, Rocha-Rodrigues S, Clemente FM, Aquino M, Nikolaidis PT, Sarmento H, Fílter A, Olivares-Jabalera J, Ramirez-Campillo R. The Hamstrings: Anatomic and Physiologic Variations and Their Potential Relationships With Injury Risk. Front Physiol 2021; 12:694604. [PMID: 34305648 PMCID: PMC8294189 DOI: 10.3389/fphys.2021.694604] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 06/16/2021] [Indexed: 01/11/2023] Open
Abstract
The incidence and recurrence of hamstrings injuries are very high in sports, posing elevated performance and financial-related costs. Attempts to identify the risk factors involved in predicting vulnerability to hamstrings injury is important for designing exercise-based programs that aim to mitigate the rate and severity of hamstrings injuries and improve rehabilitation strategies. However, research has shown that non-modifiable risk factors may play a greater role than modifiable risk factors. Recognizing non-modifiable risk factors and understanding their implications will afford the prescription of better suited exercise programs, i.e., that are more respectful of the individual characteristics. In a nutshell, non-modifiable risk factors can still be acted upon, even if indirectly. In this context, an underexplored topic is how intra and inter- individual anatomic and physiologic variations in hamstrings (e.g., muscle bellies, fiber types, tendon length, aponeurosis width, attachment sites, sex- and age-related differences) concur to alter hamstrings injuries risk. Some anatomic and physiologic variations may be modifiable through exercise interventions (e.g., cross-sectional area), while others may not (e.g., supernumerary muscle bellies). This apparent dichotomy may hide a greater complexity, i.e., there may be risk factors that are partially modifiable. Therefore, we explored the available information on the anatomic variations of the hamstrings, providing a deeper insight into the individual risk factors for hamstrings injuries and contributing with better knowledge and potential applications toward a more individualized exercise prescription.
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Affiliation(s)
- José Afonso
- Centre for Research, Education, Innovation and Intervention in Sport, Faculty of Sport of the University of Porto, Porto, Portugal
| | - Sílvia Rocha-Rodrigues
- Escola Superior de Desporto e Lazer, Instituto Politécnico de Viana do Castelo, Viana do Castelo, Portugal
- Research Centre in Sports Sciences, Health Sciences and Human Development, Vila Real, Portugal
- Tumor & Microenvironment Interactions Group, Instituto de Investigação e Inovação em Saúde, Porto, Portugal
| | - Filipe M. Clemente
- Escola Superior de Desporto e Lazer, Instituto Politécnico de Viana do Castelo, Viana do Castelo, Portugal
- Instituto de Telecomunicações, Delegação da Covilhã, Covilhã, Portugal
| | - Michele Aquino
- Department of Health and Sport Sciences, Adelphi University, New York, NY, United States
| | | | - Hugo Sarmento
- Research Unit for Sport and Physical Activity, Faculty of Sport Sciences and Physical Education, University of Coimbra, Coimbra, Portugal
| | - Alberto Fílter
- FSI Sport Research Lab, Football Science Institute, Granada, Spain
- Research Group Physical Activity, Health and Sport CTS-948, University of Pablo de Olavide, Seville, Spain
| | - Jesús Olivares-Jabalera
- FSI Sport Research Lab, Football Science Institute, Granada, Spain
- Sport and Health University Research Institute, Department of Physical and Sports Education, University of Granada, Granada, Spain
| | - Rodrigo Ramirez-Campillo
- Department of Physical Activity Sciences, Universidad de Los Lagos, Santiago, Chile
- Centro de Investigación en Fisiología del Ejercicio, Facultad de Ciencias, Universidad Mayor, Santiago, Chile
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18
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Specificity of eccentric hamstring training and the lack of consistency between strength assessments using conventional test devices. Sci Rep 2021; 11:13417. [PMID: 34183742 PMCID: PMC8239011 DOI: 10.1038/s41598-021-92929-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 06/16/2021] [Indexed: 12/11/2022] Open
Abstract
Hamstring injuries are endemic, but influences of test-specific training and the application of different test methods on decision making remain elusive. Sport-students were randomised to isokinetic (IG) or Nordic hamstring (NG) exercise or a control group (CG) for six weeks. Training and testing procedures were matched to biomechanical parameters. Hamstring strength (EPT), work, muscle soreness (visual analogue scale (VAS)), biceps femoris (BFlh) muscle size and architecture were assessed. Anthropometrics and strength parameters did not differ at baseline. Yet, body mass normalised EPT, and work revealed a significant group × time × device effect, with a significant main effect for devices. Experimental conditions triggered meaningful increases in EPT compared to the control group, but the effects were higher when recorded on the training device. Despite significant group × time interactions, normalised average work on the NHD was only higher in the NG compared to CG of the left leg (+ 35%). No effects were found for BFlh parameters. Hamstrings showed a high training specificity, but adaptations likely remain undetected owing to the low sensitivity of conventional test devices. Moreover, strength increase of ~ 15% does not necessarily have to be reflected in BFlh parameters.
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19
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Raiteri BJ, Beller R, Hahn D. Biceps Femoris Long Head Muscle Fascicles Actively Lengthen During the Nordic Hamstring Exercise. Front Sports Act Living 2021; 3:669813. [PMID: 34179775 PMCID: PMC8219857 DOI: 10.3389/fspor.2021.669813] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 04/21/2021] [Indexed: 11/28/2022] Open
Abstract
Current debate exists around whether a presumed eccentric exercise, the Nordic hamstring exercise (NHE), actually causes active hamstring muscle lengthening. This is because of the decoupling that can occur between the muscle fascicle and muscle-tendon unit (MTU) length changes in relatively compliant human lower-limb MTUs, which results in MTU lengthening not necessarily causing muscle fascicle lengthening. This missing knowledge complicates the interpretation of why the NHE is effective at reducing running-related hamstring muscle injury risk in athletes previously unfamiliar with performing this exercise. The purpose of the study was therefore to investigate if the most-commonly injured hamstring muscle, the biceps femoris long head (BF), exhibits active muscle lengthening (i.e. an eccentric muscle action) during the NHE up until peak force in Nordic novices. External reaction force at the ankle, knee flexion angle, and BF and semitendinosus muscle activities were recorded from the left leg of 14 participants during the NHE. Simultaneously, BF muscle architecture was imaged using B-mode ultrasound imaging, and muscle architecture changes were tracked using two different tracking algorithms. From ~85 to 100% of peak NHE force, both tracking algorithms detected that BF muscle fascicles (n = 10) significantly lengthened (p < 0.01) and had a mean positive lengthening velocity (p ≤ 0.02), while knee extension velocity remained positive (17°·s−1) over knee flexion angles from 53 to 37° and a duration of 1.6 s. Despite some individual cases of brief isometric fascicle behavior and brief fascicle shortening during BF MTU lengthening, the predominant muscle action was eccentric under a relatively high muscle activity level (59% of maximum). Eccentric hamstring muscle action therefore does occur during the NHE in relatively strong (429 N) Nordic novices, which might contribute to the increase in resting BF muscle fascicle length and reduction in running-related injury risk, which have previously been reported following NHE training. Whether an eccentric BF muscle action occurs in individuals accustomed to the NHE remains to be tested.
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Affiliation(s)
- Brent J Raiteri
- Human Movement Science, Faculty of Sport Science, Ruhr University Bochum, Bochum, Germany
| | - Ronja Beller
- Human Movement Science, Faculty of Sport Science, Ruhr University Bochum, Bochum, Germany.,Department of Pediatric Hematology/Oncology, Center for Child and Adolescent Medicine, Essen University Hospital, Essen, Germany
| | - Daniel Hahn
- Human Movement Science, Faculty of Sport Science, Ruhr University Bochum, Bochum, Germany.,School of Human Movement and Nutrition Sciences, The University of Queensland, Brisbane, QLD, Australia
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20
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Bautista IJ, Vicente-Mampel J, Baraja-Vegas L, Segarra V, Martín F, Van Hooren B. The effects of the Nordic hamstring exercise on sprint performance and eccentric knee flexor strength: A systematic review and meta-analysis of intervention studies among team sport players. J Sci Med Sport 2021; 24:931-938. [PMID: 33893033 DOI: 10.1016/j.jsams.2021.03.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 02/23/2021] [Accepted: 03/09/2021] [Indexed: 11/19/2022]
Abstract
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 20m) 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 Electronic databases were searched until the 20th of June 2020. 17 studies met the inclusion criteria. Random-effects meta-analyses were used to determine the mean difference (MD) or standardized change of mean difference (SCMD) between NHE and control group for sprint time and ESKF, respectively. RESULTS NHE interventions showed a positive effect on sprint performance (-0.04s [-0.08, -0.01]). Sub-group meta-analyses indicated no significant differences in 5 and 20m sprint performance (MDsprint(5m)=-0.02s [-0.10, 0.06]) and (MD sprint(20m)=-0.05s [-0.30, 0.19]), respectively. A significant difference was however found for 10m sprint performance (MDsprint(10m)=-0.06s [-0.10, -0.01]). Meta-analysis on the effects of the NHE on ESKF showed a significant benefit of 0.83 SCMD [0.55, 1.12] in favour of the intervention group. CONCLUSIONS Studies with some concerns or high risk of bias show that training programs involving the NHE can have small beneficial effects on sprint performance in team sport players. Studies with some concerns or high risk of bias showed moderate beneficial effects on ESKF among a sample of relatively untrained individuals. However, for well-trained team sport players, the improvements in ESKF were less consistent, suggesting a higher training intensity during the NHE may be required to induce adaptations.
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Affiliation(s)
- Iker J Bautista
- Department of Physiotherapy, Catholic University of Valencia, Spain.
| | | | | | - Víctor Segarra
- ProElite Performance, CESADE Physiotherapist Clinic, Spain
| | - Fernando Martín
- Department of Physical Education and Sports, University of Valencia, Spain
| | - Bas Van Hooren
- Department of Nutrition and Movement Sciences, UNTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, The Netherlands
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21
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Ruan M, Li L, Zhu W, Huang T, Wu X. The Relationship Between the Contact Force at the Ankle Hook and the Hamstring Muscle Force During the Nordic Hamstring Exercise. Front Physiol 2021; 12:623126. [PMID: 33767632 PMCID: PMC7985830 DOI: 10.3389/fphys.2021.623126] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 02/08/2021] [Indexed: 11/23/2022] Open
Abstract
A novel device has been developed to assess eccentric hamstring strength during the Nordic hamstring exercise (NHE) by measuring the contact force at the ankle hook (brace). The purpose of this study was to determine the correlation between the force measured at the ankle hook and the hamstring force estimated by a low extremity model. Thirteen male college sprinters were recruited to perform NHE on an instrumented device Nordbord (Vald Performance, Australia). Contact forces were measured at a sampling rate of 50 Hz at the hooks using the uniaxial load cells. 3D kinematics were measured simultaneously at a sampling rate of 200 Hz using a 16-camera motion analysis system (Vicon Motion Analysis, Oxford, United Kingdom) during the NHE. The data were processed with Visual 3D (C-Motion, Germantown, MD, United States) and OpenSim (NCSRR, Stanford, CA, United States) to calculate the knee joint center’s coordinates and hamstring moment arms during NHE. A static low extremity model was built to estimate the hamstring force during NHE. We have observed a significant but not very high correlation (r2 = 0.58) between peak hamstring force and the peak contact force at the ankle hook. The peak contact force measured at the ankle hook can only explain a little more than half of the variations in peak hamstring muscle forces during NHE. Caution must be exercised when assessing the eccentric hamstring strength using the ankle contact force during NHE.
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Affiliation(s)
- Mianfang Ruan
- Sports Biomechanics Laboratory, College of Physical Education and Health, Wenzhou University, Wenzhou, China
| | - Li Li
- Department of Health Sciences and Kinesiology, Georgia Southern University, Statesboro, GA, United States
| | - Weiping Zhu
- School of Kinesiology, Shanghai University of Sport, Shanghai, China
| | - Tianchen Huang
- Sports Biomechanics Laboratory, College of Physical Education and Health, Wenzhou University, Wenzhou, China
| | - Xie Wu
- School of Kinesiology, Shanghai University of Sport, Shanghai, China
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22
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Sherman DA, Glaviano NR, Norte GE. Hamstrings Neuromuscular Function After Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-Analysis. Sports Med 2021; 51:1751-1769. [PMID: 33609272 DOI: 10.1007/s40279-021-01433-w] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/01/2021] [Indexed: 12/23/2022]
Abstract
BACKGROUND Hamstrings neuromuscular function is a crucial component of functional movement, and changes after anterior cruciate ligament (ACL) injury contribute to risk factors for secondary injury and long-term sequelae. To effectively treat muscular impairments, an accurate understanding of hamstrings neuromuscular function in patients with ACL reconstruction (ACLR) is needed. OBJECTIVE A systematic review and meta-analysis were undertaken to describe and quantify hamstrings neuromuscular function in individuals with ACLR compared to controls. METHODS We searched PubMed, Web of Science, SPORTDiscus, CINAHL, and EBSCOhost databases in October of 2020 for studies evaluating the difference between hamstrings electromyography (EMG) between individuals with ACLR and controls. Two independent reviewers assessed each paper for inclusion and quality. Means and standard deviations were extracted from each included study to allow random-effect size (ES) meta-analysis calculations for comparison of results. RESULTS Thirty-four studies were included for final review. From these, 5 categories of neuromuscular outcomes were identified, and studies were grouped accordingly: (1) muscle activation levels (EMG amplitude), (2) co-activation, (3) onset timing, (4) electromechanical delay, and (5) time-to-peak activity. Moderate to strong evidence indicates that individuals with ACLR demonstrate higher hamstrings EMG amplitude (normalized to % maximum voluntary isometric contraction) and hamstrings-to-quadriceps co-activation during gait and stair ambulation compared to controls. In addition, there was moderate evidence of longer electromechanical delay during knee flexion and greater hamstrings-to-quadriceps co-activation during knee extension compared to controls. CONCLUSIONS Greater hamstrings EMG amplitude and co-activation during gait and ambulation tasks and longer electromechanical delay of the hamstrings in individuals with ACLR align with clinical impairments following ACLR and have implications for re-injury risk and long-term joint health, thus warranting attention in rehabilitation.
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Affiliation(s)
- David A Sherman
- School of Exercise and Rehabilitation Sciences, College of Health and Human Services, The University of Toledo, 2801 W. Bancroft St., HH 2505E, Mail Stop 119, Toledo, OH, 43606, USA.
| | - Neal R Glaviano
- Department of Kinesiology, College of Agriculture, Health and Natural Resources, University of Connecticut, Storrs, CT, USA
| | - Grant E Norte
- School of Exercise and Rehabilitation Sciences, College of Health and Human Services, The University of Toledo, 2801 W. Bancroft St., HH 2505E, Mail Stop 119, Toledo, OH, 43606, USA
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23
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Effect of Knee Joint Angle on Regional Hamstrings Activation During Isometric Knee-Flexion Exercise. J Sport Rehabil 2021; 30:905-910. [PMID: 33571961 DOI: 10.1123/jsr.2020-0181] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 11/28/2020] [Accepted: 11/29/2020] [Indexed: 12/16/2022]
Abstract
CONTEXT Each hamstring muscle is subdivided into several regions by multiple motor nerve branches, which implies each region has different muscle activation properties. However, little is known about the muscle activation of each region with a change in the knee joint angle. Understanding of regional activation of the hamstrings could be helpful for designing rehabilitation and training programs targeted at strengthening a specific region. OBJECTIVE To investigate the effect of knee joint angle on the activity level of several regions within the individual hamstring muscles during isometric knee-flexion exercise with maximal effort (MVCKF). DESIGN Within-subjects repeated measures. SETTING University laboratory. PARTICIPANTS Sixteen young males with previous participation in sports competition and resistance training experience. INTERVENTION The participants performed 2 MVCKF trials at each knee joint angle of 30°, 60°, and 90°. OUTCOME MEASURES Surface electromyography was used to measure muscle activity in the proximal, middle, and distal regions of the biceps femoris long head (BFlh), semitendinosus, and semimembranosus of hamstrings at 30°, 60°, and 90° of knee flexion during MVCKF. RESULTS Muscle activity levels in the proximal and middle regions of the BFlh were higher at 30° and 60° of knee flexion than at 90° during MVCKF (all: P < .05). Meanwhile, the activity levels in the distal region of the BFlh were not different among all of the evaluated knee joint angles. In semitendinosus and semimembranosus, the activity levels were higher at 30° and 60° than at 90°, regardless of region (all: P < .05). CONCLUSION These findings suggest that the effect of knee joint angle on muscle activity level differs between regions of the BFlh, whereas that is similar among regions of semitendinosus and semimembranosus during MVCKF.
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24
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Raya-Gonzalez J, Castillo D, Clemente FM. Injury prevention of hamstring injuries through exercise interventions. J Sports Med Phys Fitness 2021; 61:1242-1251. [PMID: 33480508 DOI: 10.23736/s0022-4707.21.11670-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
INTRODUCTION Hamstring injuries are the most prevalent time-loss injuries in sport, mainly in those modalities characterized by high-intensity and short-term actions, especially accelerations and decelerations during high-speed running. Expanding the knowledge about this type of injury and its preventive programs could be a key strategy to reduce the hamstring injury incidence. Thus, this review aimed to study the effectiveness of different preventive programs based on exercise interventions on reducing the hamstring injury incidence in athletes. EVIDENCE ACQUISITION An umbrella review was conducted through of PubMed/MEDLINE, Scopus, SPORTDiscus, Web of Science, Cochrane Library and Physiotherapy Evidence Database databases. The methodological quality of the included systematic reviews was assessed through the Assessing the Methodological Quality of Systematic Reviews 2 and the quality of the evidence was evaluated using the modified Grading of Recommendations Assessment, Development and Evaluation principles. EVIDENCE SYNTHESIS Eight systematic reviews and meta-analysis (40 primary studies) met the inclusion criteria, which included interventions based on eccentric strength, Nordic hamstring, proprioceptive training, stretching, FIFA11 and combined programs. From the qualitative synthesizes, three studies showed that eccentric-based training programs were effective; seventeen studies reported that Nordic hamstring-based programs were effective; three studies observed that stability training-based interventions were effective; two studies indicated that flexibility were effective; three studies claimed that FIFA11+based programs were effective; and two studies reported that combined programs were effective. CONCLUSIONS Exercise is a key strategy to reduce the hamstring injury incidence, being programs based on eccentric strength mainly by means of Nordic hamstring exercise, and on stability training, those programs which reported greater effectiveness.
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Affiliation(s)
| | | | - Filipe M Clemente
- School of Sport and Leisure, Polytechnic Institute of Viana do Castelo, Viana do Castelo, Portugal
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25
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Alt T, Severin J, Komnik I, Nodler YT, Benker R, Knicker AJ, Brüggemann GP, Strüder HK. Nordic Hamstring Exercise training induces improved lower-limb swing phase mechanics and sustained strength preservation in sprinters. Scand J Med Sci Sports 2020; 31:826-838. [PMID: 33341995 DOI: 10.1111/sms.13909] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 12/01/2020] [Accepted: 12/03/2020] [Indexed: 11/30/2022]
Abstract
Nordic Hamstring Exercise (NHE) training improves eccentric hamstring strength and sprint performance. However, detraining causes rapid reductions of achieved adaptations. Furthermore, the transfer of improved hamstring capacity to swing phase mechanics of sprints is unknown. This longitudinal study aimed (a) to quantify NHE-induced adaptations by camera-based isokinetic assessments and sprint analyses, (b) to relate the magnitude of adaptations to the participants' initial performance level, (c) to investigate the transferability to sprints, and (4) to determine strength preservations after 3 months. Twelve sprinters (21 years, 1.81 m, 74 kg) were analyzed throughout 22 weeks. They performed maximal sprints and eccentric knee flexor and concentric knee extensor tests before and after a 4-week NHE training. Sprints and isokinetic tests were captured by ten and four high-speed cameras. The dynamic control ratio at the equilibrium point (DCRe) evaluated thigh muscle balance. High-intensity NHE training elicited significant improvements of hamstring function (P range: <.001-.011, d range: 0.44-1.14), thigh muscle balance (P < 0.001, d range: 0.80-1.08) and hamstring-related parameters of swing phase mechanics (P range: <0.001-0.022, d range: 0.12-0.57). Sprint velocity demonstrated small increases (+1.4%, P < 0.001, d = 0.26). Adaptations of hamstring function and thigh muscle balance revealed moderate to strong transfers to improved sprint mechanics (P range: <0.001-0.048, R2 range: 34%-83%). The weakest participants demonstrated the highest adaptations of isokinetic parameters (P range: 0.003-0.023, R2 range: 42%-62%), whereas sprint mechanics showed no effect of initial performance level. Three months after the intervention, hamstring function (+6% to +14%) and thigh muscle balance (+8% to +10%) remained significantly enhanced (P < 0.001, ƞp 2 range: 0.529-0.621). High-intensity NHE training induced sustained improved hamstring function of sprinters, which can be transferred to swing phase mechanics of maximal sprints. The initial performance level, NHE training procedures and periodization should be considered to optimize adaptations.
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Affiliation(s)
- Tobias Alt
- Department of Biomechanics, Performance Analysis and Strength & Conditioning, Olympic Training and Testing Centre Westphalia, Dortmund, Germany.,Institute of Movement and Neuroscience, German Sport University, Cologne, Germany
| | - Jannik Severin
- Institute of Movement and Neuroscience, German Sport University, Cologne, Germany
| | - Igor Komnik
- Institute of Biomechanics and Orthopaedics, German Sport University, Cologne, Germany
| | - Yannick T Nodler
- Institute of Movement and Neuroscience, German Sport University, Cologne, Germany
| | - Rita Benker
- Institute of Biomechanics and Orthopaedics, German Sport University, Cologne, Germany
| | - Axel J Knicker
- Institute of Movement and Neuroscience, German Sport University, Cologne, Germany.,Research Centre for Elite Sports, Momentum, Cologne, Germany
| | - Gert-Peter Brüggemann
- Institute of Biomechanics and Orthopaedics, German Sport University, Cologne, Germany
| | - Heiko K Strüder
- Institute of Movement and Neuroscience, German Sport University, Cologne, Germany.,Research Centre for Elite Sports, Momentum, Cologne, Germany
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26
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Chesterton P, Evans W, Wright M, Lolli L, Richardson M, Atkinson G. Influence of Lumbar Mobilizations During the Nordic Hamstring Exercise on Hamstring Measures of Knee Flexor Strength, Failure Point, and Muscle Activity: A Randomized Crossover Trial. J Manipulative Physiol Ther 2020; 44:1-13. [PMID: 33248746 DOI: 10.1016/j.jmpt.2020.09.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 09/11/2020] [Accepted: 09/11/2020] [Indexed: 11/19/2022]
Abstract
OBJECTIVE The aims of this study were to quantify the effects of spinal mobilization on force production, failure point, and muscle activity of the hamstrings during the Nordic hamstring exercise (NHE), and to explore individual differences in responses. METHODS In a replicated randomized crossover trial, 24 asymptomatic, recreationally active men (age [mean ± standard deviation]: 27 ± 6 years; body mass: 82 ± 17 kg; height: 181 ± 8 cm) completed 2 standardized intervention trials (L4/5 zygapophyseal mobilizations) and 2 control trials. The failure point of the NHE was determined with 3D motion capture. Peak force, knee flexor torque, and electromyography (EMG) of the biceps femoris were measured. Data analyses were undertaken to quantify mean intervention response and explore any individual response heterogeneity. RESULTS Mean (95% confidence interval) left-limb force was higher in intervention than in control trials by 18.7 (4.6-32) N. Similarly, right-limb force was higher by 22.0 (3.4-40.6) N, left peak torque by 0.14 (0.06-0.22) N • m, and right peak torque by 0.14 (0.05-0.23) N • m/kg. Downward force angle was decreased in intervention vs control trials by 4.1° (0.5°-7.6°) on the side of application. Both peak EMG activity (P = .002), and EMG at the downward force (right; P = .020) increased in the intervention condition by 16.8 (7.1-26.4) and 8.8 (1.5-16.1) mV, respectively. Mean downward acceleration angle changed by only 0.3° (-8.9° to 9.4°) in intervention vs control trials. A clear response heterogeneity was indicated only for right force (Participant × Intervention interaction: P = .044; response heterogeneity standard deviation = 34.5 [5.7-48.4] N). Individual response heterogeneity was small for all other outcomes. CONCLUSION After spinal mobilization, immediate changes in bilateral hamstring force production and peak torque occurred during the NHE. The effect on the NHE failure point was unclear. Electromyographic activity increased on the ipsilateral side. Response heterogeneity was generally similar to the random trial-to-trial variability inherent in the measurement of the outcomes.
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Affiliation(s)
- Paul Chesterton
- School of Health and Life Sciences, Teesside University, Middlesbrough, United Kingdom.
| | - Will Evans
- Faculty of Health Sciences and Wellbeing, Sunderland University, Sunderland, United Kingdom
| | - Matthew Wright
- School of Health and Life Sciences, Teesside University, Middlesbrough, United Kingdom
| | - Lorenzo Lolli
- Football Exchange, Research Institute of Sport Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Mark Richardson
- School of Health and Life Sciences, Teesside University, Middlesbrough, United Kingdom
| | - Greg Atkinson
- School of Health and Life Sciences, Teesside University, Middlesbrough, United Kingdom
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27
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Effect of Nordic Hamstring Exercise Training on Knee Flexors Eccentric Strength and Fascicle Length: A Systematic Review and Meta-Analysis. J Sport Rehabil 2020; 30:482-491. [PMID: 33049705 DOI: 10.1123/jsr.2019-0388] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 05/11/2020] [Accepted: 07/06/2020] [Indexed: 11/18/2022]
Abstract
CONTEXT Nordic hamstring exercise (NHE) has been widely employed to prevent hamstring strain injuries. However, it is still not clear which adaptations are responsible for the NHE preventive effects. OBJECTIVES The aim of this study was to investigate the effects of NHE on knee flexors eccentric strength and fascicle length. EVIDENCE ACQUISITION The search strategy included MEDLINE, PEDro, and Cochrane CENTRAL from inception to April 2020. Randomized clinical trials that have analyzed the effects of NHE training on hamstring eccentric strength and/or fascicle length were included. EVIDENCE SYNTHESIS From the 1932 studies identified, 12 were included in the systematic review, and 9 studies presented suitable data for the meta-analysis. All studies demonstrated strength increments in response to NHE training (10%-15% and 16%-26% in tests performed on the isokinetic dynamometer and on the NHE device, respectively), as well as significant enhancement of biceps femoris long head fascicle length (12%-22%). Meta-analysis showed NHE training was effective to increase knee flexors eccentric strength assessed with both isokinetic tests (0.68; 95% confidence interval, 0.29 to 1.06) and NHE tests (1.11; 95% confidence interval, 0.62 to 1.61). NHE training was also effective to increase fascicle length (0.97; 95% confidence interval, 0.46 to 1.48). CONCLUSIONS NHE training has the potential of increasing both knee flexors eccentric strength and biceps femoris long head fascicle length.
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28
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The Effect of Nordic Hamstring Exercise Intervention Volume on Eccentric Strength and Muscle Architecture Adaptations: A Systematic Review and Meta-analyses. Sports Med 2020; 50:83-99. [PMID: 31502142 PMCID: PMC6942028 DOI: 10.1007/s40279-019-01178-7] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Background Although performance of the Nordic hamstring exercise (NHE) has been shown to elicit adaptations that may reduce hamstring strain injury (HSI) risk and occurrence, compliance in NHE interventions in professional soccer teams is low despite a high occurrence of HSI in soccer. A possible reason for low compliance is the high dosages prescribed within the recommended interventions. The aim of this review was to investigate the effect of NHE-training volume on eccentric hamstring strength and biceps femoris fascicle length adaptations. Methods A literature search was conducted using the SPORTDiscus, Ovid, and PubMed databases. A total of 293 studies were identified prior to application of the following inclusion criteria: (1) a minimum of 4 weeks of NHE training was completed; (2) mean ± standard deviation (SD) pre- and post-intervention were provided for the measured variables to allow for secondary analysis; and (3) biceps femoris muscle architecture was measured, which resulted in 13 studies identified for further analysis. The TESTEX criteria were used to assess the quality of studies with risk of bias assessment assessed using a fail-safe N (Rosenthal method). Consistency of studies was analysed using I2 as a test of heterogeneity and secondary analysis of studies included Hedges’ g effect sizes for strength and muscle architecture variables to provide comparison within studies, between-study differences were estimated using a random-effects model. Results A range of scores (3–11 out of 15) from the TESTEX criteria were reported, showing variation in study quality. A ‘low risk of bias’ was observed in the randomized controlled trials included, with no study bias shown for both strength or architecture (N = 250 and 663, respectively; p < 0.001). Study consistency was moderate to high for strength (I2 = 62.49%) and muscle architecture (I2 = 88.03%). Within-study differences showed that following interventions of ≥ 6 weeks, very large positive effect sizes were seen in eccentric strength following both high volume (g = 2.12) and low volume (g = 2.28) NHE interventions. Similar results were reported for changes in fascicle length (g ≥ 2.58) and a large-to-very large positive reduction in pennation angle (g ≥ 1.31). Between-study differences were estimated to be at a magnitude of 0.374 (p = 0.009) for strength and 0.793 (p < 0.001) for architecture. Conclusions Reducing NHE volume prescription does not negatively affect adaptations in eccentric strength and muscle architecture when compared with high dose interventions. These findings suggest that lower volumes of NHE may be more appropriate for athletes, with an aim to increase intervention compliance, potentially reducing the risk of HSI.
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29
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Drury B, Green T, Ramirez-Campillo R, Moran J. Influence of Maturation Status on Eccentric Hamstring Strength Improvements in Youth Male Soccer Players After the Nordic Hamstring Exercise. Int J Sports Physiol Perform 2020; 15:990-996. [PMID: 32188789 DOI: 10.1123/ijspp.2019-0184] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 10/05/2019] [Accepted: 10/19/2019] [Indexed: 11/18/2022]
Abstract
PURPOSE This study examined the effects of a 6-week Nordic hamstring exercise (NHE) program in youth male soccer players of less mature (pre-peak height velocity [PHV]) or more mature (mid/post-PHV) status. METHODS Forty-eight participants were separated into pre-PHV (11.0 [0.9] y) or mid/post-PHV (13.9 [1.1]) groups and further divided into experimental (EXP) and control groups with eccentric hamstring strength assessed (NordBord) both before and after the training program. Participants in the EXP groups completed a periodized NHE program performed once or twice weekly over a 6-week period. RESULTS The NHE program resulted in moderate and small increases in relative eccentric hamstring strength (in newtons per kilogram) in the pre-PHV EXP (d = 0.83 [0.03-1.68]) and mid-PHV EXP (d = 0.53 [-0.06 to 1.12]) groups, respectively. Moderate increases in the same measure were also seen in the between-groups analyses in the pre-PHV (d = 1.03 [0.23-1.84]) and mid-PHV (d = 0.87 [0.22-1.51]) groups, with a greater effect observed in the former. CONCLUSION The results from this study demonstrate that a 6-week NHE program can improve eccentric hamstring strength in male youth soccer players, with less-mature players achieving mostly greater benefits. The findings from this study can aid in the training prescription of NHE in youth male soccer players.
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Medeiros TM, Ribeiro-Alvares JB, Fritsch CG, Oliveira GS, Severo-Silveira L, Pappas E, Baroni BM. Effect of Weekly Training Frequency With the Nordic Hamstring Exercise on Muscle-Strain Risk Factors in Football Players: A Randomized Trial. Int J Sports Physiol Perform 2020; 15:1026-1033. [PMID: 32580161 DOI: 10.1123/ijspp.2018-0780] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 09/23/2019] [Accepted: 10/30/2019] [Indexed: 11/18/2022]
Abstract
PURPOSE To examine the differences between performing Nordic hamstring exercises once or twice a week on hamstring eccentric strength and other muscle-strain risk factors in high-level football players. METHODS In this randomized trial, 32 football players (18-23 y old) completed an 8-week Nordic hamstring exercise training program in 1 of 2 experimental groups: group 1 (once a week; n = 15) and group 2 (twice a week; n = 17). Knee-flexor/extensor peak torques and biceps femoris long-head muscle architecture were assessed through isokinetic dynamometry and ultrasonography, respectively, before and after the training programs. Analysis of covariance, effect sizes (ESs), and t tests for percentage change were used to assess the effect of the 2 interventions on the outcome measures. RESULTS Group 2 demonstrated higher hamstring concentric peak torque than group 1 posttraining (155-164 vs 149-158 N·m; P = .043; ES = 0.27), although there was also a statistical trend for higher hamstring eccentric peak torque (212-234 vs 198-221 N·m; P = .098; ES = 0.37), hamstring-to-quadriceps conventional ratio (0.56-0.59 vs 0.54-0.57; P = .089; ES = 0.31), and hamstring-to-quadriceps functional ratio (0.76-0.84 vs 0.71-0.79; P = .076; ES = 0.50). No between-groups differences were found for muscle thickness (P = .864; ES = 0.12), pennation angle (P = .289; ES = 0.18), fascicle length (P = .406; ES = 0.03), and quadriceps concentric peak torque (P = .340; ES = 0.02). CONCLUSION Only the Nordic hamstring exercise training program performed twice a week strengthened the hamstrings of high-level football players, while similar changes in muscle architecture occurred with both once- and twice-weekly sessions.
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31
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Marušič J, Vatovec R, Marković G, Šarabon N. Effects of eccentric training at long-muscle length on architectural and functional characteristics of the hamstrings. Scand J Med Sci Sports 2020; 30:2130-2142. [PMID: 32706442 DOI: 10.1111/sms.13770] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Revised: 07/07/2020] [Accepted: 07/10/2020] [Indexed: 12/30/2022]
Abstract
Hamstring strain injuries during sprinting or stretching frequently occur at long-muscle length. Yet, previous research has mainly focused on studying the effectiveness of eccentric hamstring strengthening at shorter muscle length on hamstring performance, morphology, and hamstring strain injury risk factors. Here, we evaluated the effects of 6-week eccentric hamstring training at long-muscle length on functional and architectural characteristics of the hamstrings. Healthy and injury-free participants (n = 40; age 23.7 ± 2.5 years) were randomly assigned to control or intervention group. Training intervention consisted of 12 sessions with two eccentric hamstring exercises in a lengthened position. Outcome measures included isokinetic and isometric knee flexion peak torque, Nordic hamstring exercise peak torque, voluntary activation level, and countermovement jump performance. Ultrasonography was used to determine muscle thickness, pennation angle, and fascicle length of biceps femoris long head (BFlh). A significant time × group interaction effect was observed for all measured parameters except countermovement jump performance and muscle thickness. The training intervention resulted in increased concentric and eccentric knee flexion peak torque at 60°/s (d = 0.55-0.62, P = .02 and .03) and concentric peak torque at 180°/s (d = 0.99, P = .001), increased isometric knee flexion peak torque (d = 0.73, P = .008) and Nordic hamstring exercise peak torque (d = 1.19, P < .001), increased voluntary activation level (d = 1.29, P < .001), decreased pennation angle (d = 1.31, P < .001), and increased fascicle length (d = 1.12, P < .001) of BFlh. These results provide evidence that short-term eccentric hamstring strengthening at long-muscle length can have significant favorable effects on various architectural and functional characteristics of the hamstrings.
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Affiliation(s)
- Jan Marušič
- Faculty of Health Sciences, University of Primorska, Izola, Slovenia
| | - Rok Vatovec
- Faculty of Health Sciences, University of Primorska, Izola, Slovenia
| | - Goran Marković
- Faculty of Kinesiology, University of Zagreb, Zagreb, Croatia.,Motus Melior Ltd., Zagreb, Croatia
| | - Nejc Šarabon
- Faculty of Health Sciences, University of Primorska, Izola, Slovenia.,Laboratory for Motor Control and Motor Behavior, S2P, Science to practice, Ltd., Ljubljana, Slovenia
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32
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Marušič J, Šarabon N. Comparison of electromyographic activity during Nordic hamstring exercise and exercise in lengthened position. Eur J Transl Myol 2020; 30:8957. [PMID: 32782761 PMCID: PMC7385688 DOI: 10.4081/ejtm.2019.8957] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 03/26/2020] [Indexed: 01/08/2023] Open
Abstract
Hamstring strain injuries remain among the most problematic and most frequent sport injuries. Two of the most effective methods for prevention and rehabilitation of the hamstring strain injuries are: classic eccentric training using the Nordic hamstring exercise (NHE) and eccentric training in a lengthened position using the glider exercise. Both exercises have disadvantages that could be fixed by adding hip flexion during the NHE. Thus, the purpose of the study was to compare peak hamstring activity (measured by electromyography) between three eccentric exercises: the standard NHE, the modified NHE and the glider. Differences were statistically tested with the analysis of the variance for repeated measurements and the paired 2-tailed post-hoc t-test. Hamstring activity during the modified NHE was significantly lower compared to the NHE and significantly higher compared to the glider. The results indicate that implementing the modified NHE could increase the effectiveness of already established rehabilitation protocols and help reduce the risk of hamstring (re-)injury.
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Affiliation(s)
- Jan Marušič
- University of Primorska, Faculty of Health Sciences, Izola, Slovenia
| | - Nejc Šarabon
- University of Primorska, Faculty of Health Sciences, Izola, Slovenia.,S2P, Science to practice, Ltd., Laboratory for Motor Control and Motor Behavior, Ljubljana, Slovenia
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33
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Burrows AP, Cleather D, Mahaffey R, Cimadoro G. Kinetic and Electromyographic Responses to Traditional and Assisted Nordic Hamstring Exercise. J Strength Cond Res 2020; 34:2715-2724. [DOI: 10.1519/jsc.0000000000003689] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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34
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Marušič J, Šarabon N. Comparison of electromyographic activity during Nordic hamstring exercise and exercises in lengthened position. Eur J Transl Myol 2020. [DOI: 10.4081/ejtm.2020.8957] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Hamstring strain injuries remain among the most problematic and most frequent sport injuries. Two of the most effective methods for prevention and rehabilitation of the hamstring strain injuries are: classic eccentric training using the Nordic hamstring exercise (NHE) and eccentric training in a lengthened position using the glider exercise. Both exercises have disadvantages that could be fixed by adding hip flexion during the NHE. Thus, the purpose of the study was to compare peak hamstring activity (measured by electromyography) between three eccentric exercises: the standard NHE, the modified NHE and the glider. Differences were statistically tested with the analysis of the variance for repeated measurements and the paired 2-tailed post-hoc t-test. Hamstring activity during the modified NHE was significantly lower compared to the NHE and significantly higher compared to the glider. The results indicate that implementing the modified NHE could increase the effectiveness of already established rehabilitation protocols and help reduce the risk of hamstring (re-)injury.
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Reproducibility of the DrGoniometer app for field-based assessment of the break-point angle in Nordic Hamstring exercise. Int J Rehabil Res 2020; 43:272-275. [PMID: 32371847 DOI: 10.1097/mrr.0000000000000415] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Smartphone-based measurement could represent a portable and cheap solution to assess the Nordic Hamstring break-point angle (BPA). We investigated the following: (1) the reproducibility of the DrGoniometer app, (2) its agreement with a computerized video analysis software used as a reference method, and (3) the effects of raters' experience. Fifty recordings were processed by four independent raters. Intraclass correlation coefficient (ICC), SEM, and minimum detectable change (MDC) were calculated. Bland-Altman plots verified the limits of agreement (LoA) with the reference method. The effect of raters' clinical experience was investigated by unpaired t-tests. The app showed excellent intra-rater (ICC = 0.89, 95% CI, 0.84-0.92) and inter-rater reliability (ICC = 0.82, 95% CI, 0.74-0.89), low error (SEM = 2°; MDC = 5.5°), and substantial agreement with video analysis [95% LoA = ±6.7°; mean difference = 1.0°]. Rater experience did not affect results (P > 0.05). The smartphone-based app offers a reliable, valid, quick, and portable method for measuring the BPA in Nordic Hamstring exercise.
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Comment On: "The Effect of Nordic Hamstring Exercise Intervention Volume on Eccentric Strength and Muscle Architecture Adaptations: A Systematic Review and Meta-Analyses". Sports Med 2020; 50:219-221. [PMID: 31820377 DOI: 10.1007/s40279-019-01244-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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37
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Cuthbert M, Ripley N, McMahon JJ, Evans M, Haff GG, Comfort P. Reply to: "Comment on: The Effect of Nordic Hamstring Exercise Intervention Volume on Eccentric Strength and Muscle Architecture Adaptations: A Systematic Review and Meta-analyses". Sports Med 2020; 50:223-225. [PMID: 31820375 DOI: 10.1007/s40279-019-01245-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Matthew Cuthbert
- Human Performance Laboratory, Directorate of Sport, Exercise, and Physiotherapy, University of Salford, Greater Manchester, UK. .,Technical Directorate Division, The FA Group, St George's Park, Burton-upon-Trent, Staffordshire, UK.
| | - Nicholas Ripley
- Human Performance Laboratory, Directorate of Sport, Exercise, and Physiotherapy, University of Salford, Greater Manchester, UK
| | - John J McMahon
- Human Performance Laboratory, Directorate of Sport, Exercise, and Physiotherapy, University of Salford, Greater Manchester, UK
| | - Martin Evans
- Technical Directorate Division, The FA Group, St George's Park, Burton-upon-Trent, Staffordshire, UK
| | - G Gregory Haff
- Human Performance Laboratory, Directorate of Sport, Exercise, and Physiotherapy, University of Salford, Greater Manchester, UK.,Centre for Exercise and Sports Sciences Research (CESSR), School of Exercise and Health Sciences, Edith Cowan University, Joondalup, Australia
| | - Paul Comfort
- Human Performance Laboratory, Directorate of Sport, Exercise, and Physiotherapy, University of Salford, Greater Manchester, UK.,Institute for Sport, Physical Activity and Leisure, Carnegie School of Sport, Leeds Beckett University, Leeds, UK
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Gérard R, Gojon L, Decleve P, Van Cant J. The Effects of Eccentric Training on Biceps Femoris Architecture and Strength: A Systematic Review With Meta-Analysis. J Athl Train 2020; 55:501-514. [PMID: 32216654 DOI: 10.4085/1062-6050-194-19] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
OBJECTIVE To determine the effects of an eccentric hamstrings strength-training program, performed for at least 4 weeks by healthy adults, on muscle architecture and eccentric strength. DATA SOURCES A systematic search was performed up to October 2018 in the following electronic databases: PubMed, PEDro, CINAHL and SPORTDiscus. Combinations of the following search terms were used: eccentric strength training, eccentric loading, nordic hamstring, hamstring strength, fascicle length, pennation angle, muscle thickness, muscle architecture, biceps femoris long head, biceps femoris, and hamstring muscles. STUDY SELECTION Included articles were randomized controlled trials that allowed comparisons between isolated eccentric strength training of the biceps femoris muscle and other programs. DATA EXTRACTION Data from the included studies were extracted by 2 independent reviewers. These data included the study design, participant characteristics, inclusion and exclusion criteria of clinical studies, exercise and intervention characteristics, outcome measures, and the main results of the study. When meta-analysis was possible, we performed quantitative analysis. Ten randomized controlled trials were included. DATA SYNTHESIS Limited to moderate evidence indicated that eccentric strength training was associated with an increase in fascicle length (mean difference [MD] = 1.97; 95% confidence interval [CI] = 1.48, 2.46), an increase in muscle thickness (MD = 0.10; 95% CI = 0.06, 0.13), and a decrease in pennation angle (MD = 2.36; 95% CI = 1.61, 3.11). Conflicted to moderate evidence indicated that eccentric hamstrings strength was increased after eccentric strength training compared with concentric strength training (standardized mean difference [SMD] = 1.06; 95% CI = 0.26, 1.86), usual level of activity (SMD = 2.72; 95% CI = 1.68, 3.77), and static stretching (SMD = 0.39; 95% CI = -0.97, 1.75). CONCLUSIONS In healthy adults, an eccentric strength-training program produced architectural adaptations on the long head of the biceps femoris muscle and increased eccentric hamstrings strength.
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Affiliation(s)
- Rémy Gérard
- Department of Physical Therapy, Institut Parnasse-ISEI, Brussels, Belgium
| | - Léo Gojon
- Department of Physical Therapy, Institut Parnasse-ISEI, Brussels, Belgium
| | - Philippe Decleve
- Department of Physical Therapy, Institut Parnasse-ISEI, Brussels, Belgium.,Department of Rehabilitation Sciences and Physiotherapy, Faculty of Medicine and Health Sciences, University Hospital Ghent, Belgium
| | - Joachim Van Cant
- Department of Physical Therapy, Institut Parnasse-ISEI, Brussels, Belgium
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Wiesinger H, Gressenbauer C, Kösters A, Scharinger M, Müller E. Device and method matter: A critical evaluation of eccentric hamstring muscle strength assessments. Scand J Med Sci Sports 2020; 30:217-226. [PMID: 31593621 PMCID: PMC7003788 DOI: 10.1111/sms.13569] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 09/10/2019] [Accepted: 09/30/2019] [Indexed: 12/25/2022]
Abstract
Equivocal findings exist on isokinetic and Nordic hamstring exercise testing of eccentric hamstring strength capacity. Here, we propose a critical comparison of the mechanical output of hamstring muscles as assessed with either a dynamometer (IKD) or a Nordic hamstring device (NHD). Twenty-five volunteers (26 ± 3 years) took part in a counterbalanced repeated-measures protocol on both devices. Eccentric peak torque, work, angle of peak torque, bilateral strength ratios, and electromyography activity of the biceps femoris long head, semitendinosus and gastrocnemius muscles were assessed. There was a very poor correlation in eccentric peak torque between the devices (r < 0.58), with a systematic and proportional bias toward lower torque values on the IKD (~28%) and a high typical error (~19%) in IKD and NHD measurements comparison. Furthermore, participants performed a higher total eccentric work on IKD, reached peak torques at greater knee extension angles, and showed a greater side-to-side strength difference compared to the Nordic hamstring exercise. Gastrocnemius muscle activity was lower during the Nordic hamstring exercise. Reliability was low for work on NHD and for angle of peak torque and bilateral strength ratios on either device. We conclude that the evaluation of eccentric knee flexor strength depends on the testing conditions and even under standardized procedures, the IKD and NHD measure a different trait. Both tests have limitations in terms of assessing strength differences within an individual, and measurements of the angle of peak torque or side-to-side differences in eccentric knee flexor strength revealed low reliability and should be considered with caution.
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Affiliation(s)
| | | | - Alexander Kösters
- Department of Sport and Exercise ScienceUniversity of SalzburgSalzburgAustria
| | - Manuel Scharinger
- Department of Sport and Exercise ScienceUniversity of SalzburgSalzburgAustria
| | - Erich Müller
- Department of Sport and Exercise ScienceUniversity of SalzburgSalzburgAustria
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40
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Šarabon N, Marušič J, Marković G, Kozinc Ž. Kinematic and electromyographic analysis of variations in Nordic hamstring exercise. PLoS One 2019; 14:e0223437. [PMID: 31644582 PMCID: PMC6808554 DOI: 10.1371/journal.pone.0223437] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 09/20/2019] [Indexed: 11/18/2022] Open
Abstract
The purpose of this study was to present and biomechanically evaluate several variations of the Nordic hamstring exercise (NHE), achieved by altering the slope of the lower leg support and by asumming different hip flexion angles. Electromyographic and 2D kinematic measurements were conducted to analyse muscle activity (biceps femoris, semitendinosus, gluteus maximus, erector spine and lateral head of the gastrocnemius), knee and hip joint torques during 6 variations of NHE. The study involved 18 adults (24.9 ± 3.7 years) with previous experience in resistance training, but with little or no experience with NHE. Increasing the slope of the lower leg support from 0° (standard NHE) to 20° and 40° enabled the participants to perform the exercise through a larger range of motion, while achieving similar peak knee and hip torques. Instructions for increased hip flexion from 0° (standard NHE) to 25°, 50° and 75° resulted in greater peak knee and hip torque, although the participants were not able to maintain the hip angle at 50° nor 75°. Muscle activity decreased or remained similar in all modified variations compared to the standard NHE for all measured muscles. Our results suggest that using the presented variations of NHE might contribute to optimization of hamstring injury prevention and rehabilitation programs, by providing appropriate difficulty for the individual’s strength level and also allow eccentric strengthening at longer hamstring lengths.
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Affiliation(s)
- Nejc Šarabon
- University of Primorska, Faculty of Health Sciences, Izola, Slovenia
- S2P, Science to practice, Ltd., Laboratory for Motor Control and Motor Behavior, Ljubljana, Slovenia
- * E-mail:
| | - Jan Marušič
- University of Primorska, Faculty of Health Sciences, Izola, Slovenia
| | - Goran Marković
- University of Zagreb, Faculty of Kinesiology, Zagreb, Croatia
- Motus Melior Ltd., Zagreb, Croatia
| | - Žiga Kozinc
- University of Primorska, Faculty of Health Sciences, Izola, Slovenia
- University of Primorska, Andrej Marušič Institute, Koper, Slovenia
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41
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Freeman BW, Young WB, Talpey SW, Smyth AM, Pane CL, Carlon TA. The effects of sprint training and the Nordic hamstring exercise on eccentric hamstring strength and sprint performance in adolescent athletes. J Sports Med Phys Fitness 2019; 59:1119-1125. [PMID: 31332988 DOI: 10.23736/s0022-4707.18.08703-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Hamstring strain injuries (HSI) are among the most common injuries in field-based team sports with a high-speed running component. The implementation of the Nordic hamstring exercise (NHE) is a well-documented method of improving eccentric hamstring strength to mitigate the risk of HSI occurrence. Sprint training is specific to the injury mechanism and is thought to activate the hamstrings through maximal eccentric contractions. The purpose of this study was to compare the effects of sprint training and the NHE on eccentric hamstring strength and sprint performance. METHODS Twenty-eight participants (mean±SD age=16.21±1.34 years; height=1.75m±0.10m; body mass=68.5kg±12.1kg) completed an eccentric hamstring strength assessment and 40m sprint to assess acceleration and maximum speed. Participants were randomly allocated to either a NHE training or sprint training group. Two sessions per week for four-weeks of training was performed with baseline testing procedures repeated in the week following the intervention. Perceptions of soreness were recorded following the warm-up in each training session. RESULTS Both the NHE (effect size=0.39, P<0.05) and sprint training (effect size=0.29, P<0.05) groups displayed significant gains in eccentric hamstring strength. The NHE group reported trivial improvements in sprint performance, whilst the sprint training group experienced a moderate improvement, specifically in maximum speed (ES=0.83 Moderate). Sprint training also produced greater perceptions of soreness than the NHE following a four-week training intervention, specifically before the start of the last session (P<0.05). CONCLUSIONS These findings indicate that sprint training had a beneficial effect for both eccentric hamstring strength and sprint performance, whilst also producing greater soreness than the NHE following the final training session. It was concluded that a four-week block of maximum speed training may have both an injury prevention and performance enhancement benefit.
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Affiliation(s)
- Brock W Freeman
- School of Health Sciences and Psychology, Faculty of Health, Federation University Australia, Ballarat, Australia -
| | - Warren B Young
- School of Health Sciences and Psychology, Faculty of Health, Federation University Australia, Ballarat, Australia
| | - Scott W Talpey
- School of Health Sciences and Psychology, Faculty of Health, Federation University Australia, Ballarat, Australia.,School of Health and Human Services, Southern Connecticut State University, New Haven, CT, USA
| | - Andrew M Smyth
- School of Health Sciences and Psychology, Faculty of Health, Federation University Australia, Ballarat, Australia
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42
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Milanese S, Eston R. Hamstring injuries and Australian Rules football: over-reliance on Nordic hamstring exercises as a preventive measure? Open Access J Sports Med 2019; 10:99-105. [PMID: 31413646 PMCID: PMC6662172 DOI: 10.2147/oajsm.s212008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 06/06/2019] [Indexed: 12/19/2022] Open
Abstract
Nordic hamstring exercises (NHE) are promoted as an evidence-based strategy for reducing the prevalence of hamstring injuries in football, with a number of studies showing a significant reduction in hamstring injury rates following implementation of a NHE-based program. However, most of the research to date has been undertaken in soccer with less research carried out in other football codes. Despite this lack of relevant evidence, NHE has recently become popular as a preventative measure in Australian Rules football (ARF) teams; however, hamstring injuries remain high. This paper reviews the literature associated with the use of NHE for ARF players and questions the appropriateness of this exercise approach as a preventative measure for hamstring injuries in this sport. When considering the use of a preventative exercise program, such as the NHE, the specific risks associated with the sporting activity should be considered and the evidence reviewed in light of this. Whilst NHE provides an easy way to do eccentric exercises, the movement does not replicate what is needed in the real world for ARF and should therefore be included in a hamstring injury prevention program in this code with caution.
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Affiliation(s)
- Steve Milanese
- International Centre for Allied Health Evidence, University of South Australia, Adelaide, South Australia, Australia
| | - Roger Eston
- Alliance for Research in Exercise, Nutrition and Activity, University of South Australia, Adelaide, South Australia, Australia
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43
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Macdonald B, McAleer S, Kelly S, Chakraverty R, Johnston M, Pollock N. Hamstring rehabilitation in elite track and field athletes: applying the British Athletics Muscle Injury Classification in clinical practice. Br J Sports Med 2019; 53:1464-1473. [DOI: 10.1136/bjsports-2017-098971] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/10/2019] [Indexed: 12/31/2022]
Abstract
RationaleHamstring injuries are common in elite sports. Muscle injury classification systems aim to provide a framework for diagnosis. The British Athletics Muscle Injury Classification (BAMIC) describes an MRI classification system with clearly defined, anatomically focused classes based on the site of injury: (a) myofascial, (b) muscle–tendon junction or (c) intratendinous; and the extent of the injury, graded from 0 to 4. However, there are no clinical guidelines that link the specific diagnosis (as above) with a focused rehabilitation plan.ObjectiveWe present an overview of the general principles of, and rationale for, exercise-based hamstring injury rehabilitation in British Athletics. We describe how British Athletics clinicians use the BAMIC to help manage elite track and field athletes with hamstring injury. Within each class of injury, we discuss four topics: clinical presentation, healing physiology, how we prescribe and progress rehabilitation and how we make the shared decision to return to full training. We recommend a structured and targeted diagnostic and rehabilitation approach to improve outcomes after hamstring injury.
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44
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Siddle J, Greig M, Weaver K, Page RM, Harper D, Brogden CM. Acute adaptations and subsequent preservation of strength and speed measures following a Nordic hamstring curl intervention: a randomised controlled trial. J Sports Sci 2018; 37:911-920. [PMID: 30369285 DOI: 10.1080/02640414.2018.1535786] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
This randomised controlled trial investigated changes in eccentric hamstring strength, 10m sprint speed, and change-of-direction (COD) performance immediately post Nordic hamstring curl (NHC) intervention and following a 3-week detraining period. Fourteen male team sports athletes were randomised to a do-as-usual control group (CG; n = 7) or to a NHC intervention group (NHC; n = 7). Isokinetic dynamometry at 180°/s evaluated eccentric hamstring strength immediately post-intervention as the primary outcome measure. Secondary outcomes included 10 m sprint time and COD. Each outcome was measured, pre, immediately post-intervention and following a 3-week detraining period. Immediately post-intervention significant group differences were observed in the NHC group for eccentric hamstring strength (31.81 Nm-1 vs. 6.44 Nm-1, P = 0.001), COD (-0.12 s vs. 0.20 s; P = 0.003) and sprint (- 0.06 s vs. 0.05 s; P = 0.024) performance. Performance improvements were maintained following a detraining period for COD (-0.11 s vs. 0.20 s; P = 0.014) and sprint (-0.05 s vs. 0.03 s, P = 0.031) but not eccentric hamstring strength (15.67 Nm-1 vs. 6.44 Nm-1, P = 0.145) These findings have important implications for training programmes designed to reduce hamstring injury incidence, whilst enhancing physical qualities critical to sport.
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Affiliation(s)
- James Siddle
- a Sports Injuries Research Group, Department of Sport & Physical Activity , Edge Hill University , Ormskirk , UK
| | - Matt Greig
- a Sports Injuries Research Group, Department of Sport & Physical Activity , Edge Hill University , Ormskirk , UK
| | - Kristian Weaver
- a Sports Injuries Research Group, Department of Sport & Physical Activity , Edge Hill University , Ormskirk , UK
| | - Richard Michael Page
- a Sports Injuries Research Group, Department of Sport & Physical Activity , Edge Hill University , Ormskirk , UK
| | - Damian Harper
- b School of Sport , York St John University , York , UK
| | - Christopher Michael Brogden
- a Sports Injuries Research Group, Department of Sport & Physical Activity , Edge Hill University , Ormskirk , UK
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45
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Ribeiro-Alvares JB, Marques VB, Vaz MA, Baroni BM. Four Weeks of Nordic Hamstring Exercise Reduce Muscle Injury Risk Factors in Young Adults. J Strength Cond Res 2018; 32:1254-1262. [PMID: 28459795 DOI: 10.1519/jsc.0000000000001975] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Ribeiro-Alvares, JB, Marques, VB, Vaz, MA, and Baroni, BM. Four weeks of Nordic hamstring exercise reduce muscle injury risk factors in young adults. J Strength Cond Res 32(5): 1254-1262, 2018-The Nordic hamstring exercise (NHE) is a field-based exercise designed for knee-flexor eccentric strengthening, aimed at prevention of muscle strains. However, possible effects of NHE programs on other hamstring injury risk factors remain unclear. The purpose of this study was to investigate the effects of a NHE training program on multiple hamstring injury risk factors. Twenty physically active young adults were allocated into 2 equal-sized groups: control group (CG) and training group (TG). The TG was engaged in a 4-week NHE program, twice a week, 3 sets of 6-10 repetitions; while CG received no exercise intervention. The knee flexor and extensor strength were assessed through isokinetic dynamometry, the biceps femoris long head muscle architecture through ultrasound images, and the hamstring flexibility through sit-and-reach test. The results showed that CG subjects had no significant change in any outcome. TG presented higher percent changes than CG for hamstring isometric peak torque (9%; effect size [ES] = 0.27), eccentric peak torque (13%; ES = 0.60), eccentric work (18%; ES = 0.86), and functional hamstring-to-quadriceps torque ratio (13%; ES = 0.80). The NHE program led also to increased fascicle length (22%; ES = 2.77) and reduced pennation angle (-17%; ES = 1.27) in biceps femoris long head of the TG, without significant changes on muscle thickness. In conclusion, a short-term NHE training program (4 weeks; 8 training sessions) counteracts multiple hamstring injury risk factors in physically active young adults.
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Affiliation(s)
- João Breno Ribeiro-Alvares
- Graduate Program in Rehabilitation Sciences, Federal University of Health Sciences of Porto Alegre, Porto Alegre, Brazil
| | - Vanessa B Marques
- Graduate Program in Rehabilitation Sciences, Federal University of Health Sciences of Porto Alegre, Porto Alegre, Brazil
| | - Marco A Vaz
- School of Physical Education, Physiotherapy and Dance, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Bruno M Baroni
- Graduate Program in Rehabilitation Sciences, Federal University of Health Sciences of Porto Alegre, Porto Alegre, Brazil
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46
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Severini G, Holland D, Drumgoole A, Delahunt E, Ditroilo M. Kinematic and electromyographic analysis of the Askling L-Protocol for hamstring training. Scand J Med Sci Sports 2018; 28:2536-2546. [PMID: 30171776 DOI: 10.1111/sms.13288] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 08/12/2018] [Accepted: 08/29/2018] [Indexed: 11/28/2022]
Abstract
Hamstring injuries are common in field sport athletes. Eccentric strength training of the hamstring muscles is an integral component of rehabilitation programs. The Askling L-Protocol comprises three exercises [extender; diver; glider] that load the hamstrings during eccentric activity. When compared to a conventional exercise-based rehabilitation program, the Askling L-Protocol has been shown to reduce the time to return to sport following hamstring injury and prevalence of injury recurrence. Nevertheless, the mechanisms behind its efficacy have yet to be studied. In this work, we conducted a kinematic and electromyographic analysis of the exercises of the Askling L-Protocol. Eleven healthy individuals performed each of the exercises while electromyographic data from four muscles (including two hamstring muscles) were recorded. Hip and knee angular displacements and velocities were also synchronously recorded using a motion capture system. We found that the L-Protocol elicits a maximal contraction (up to 60% of the MVC in the glider exercise) in the hamstring muscles at a work point similar to the swing phase of running (around 62 degrees hip flexion and 23 degrees knee flexion). No difference in the levels of activation of the hamstrings was observed between the diver and glider, regardless of the different functional role they had in the two exercises. During the extender, the hamstring muscles are stretched and minimally engaged. Finally, co-activation analysis highlighted that through the combination of passive stretch and active eccentric contraction, the hamstrings are trained to co-activate using similar structural modules employed differentially to drive the movement or stabilize it.
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Affiliation(s)
- Giacomo Severini
- School of Electrical and Electronic Engineering, University College Dublin, Dublin, Ireland
| | - Donal Holland
- School of Mechanical and Materials Engineering, University College Dublin, Dublin, Ireland
| | - Aisling Drumgoole
- School of Electrical and Electronic Engineering, University College Dublin, Dublin, Ireland
| | - Eamonn Delahunt
- School of Public Health, Physiotherapy and Sports Science, University College Dublin, Dublin, Ireland
| | - Massimiliano Ditroilo
- School of Public Health, Physiotherapy and Sports Science, University College Dublin, Dublin, Ireland.,Institute for Sport and Health, University College Dublin, Dublin, Ireland
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47
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Blandford L, McNeill W, Charvet I. Can we spread the risk? A demand-share perspective to sustained hamstring health. J Bodyw Mov Ther 2018; 22:766-779. [PMID: 30100311 DOI: 10.1016/j.jbmt.2018.06.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Lincoln Blandford
- Movement Performance Solutions Ltd, The Quorum, Bond Street South, Bristol, BS1 3AE, UK.
| | | | - Ingrid Charvet
- Department of Civil, Environmental & Geomatic Engineering, University College London, WC1E 6BT, UK.
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48
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WITHDRAWN: Can we spread the risk? A demand-share perspective to sustained hamstring health. Biomaterials 2018. [DOI: 10.1016/j.biomaterials.2018.06.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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49
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Narouei S, Imai A, Akuzawa H, Hasebe K, Kaneoka K. Hip and trunk muscles activity during nordic hamstring exercise. J Exerc Rehabil 2018. [PMID: 29740557 PMCID: PMC5931159 DOI: 10.12965//jer.1835200.600] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The nordic hamstring exercise (NHE) is a dynamic lengthening hamstring exercise that requires trunk and hip muscles activation. Thigh muscles activation, specifically hamstring/quadriceps contractions has been previously examined during NHE. Trunk and hip muscles activity have not been enough studied. The aim of this study was to analyze of hip and trunk muscles activity during NHE. Surface electromyography (EMG) and kinematic data were collected during NHE. Ten healthy men with the age range of 21–36 years performed two sets of two repetitions with downward and upward motions each of NHE. EMG activity of fifteen trunk and hip muscles and knee kinematic data were collected. Muscle activity levels were calculated through repeated measure analysis of variance in downward and upward motions, through Paired t-test between downward and upward motions and gluteus maximus to erector spine activity ratio (Gmax/ES ratio) using Pearson correlation analyses were evaluated. Semitendinosus and biceps femoris muscles activity levels were the greatest in both motions and back extensors and internal oblique muscles activity were greater than other muscles (P<0.05). The decreased Gmax/ES ratio was significantly related to peak knee extension angle in downward (r=0.687) and upward motions (r=0.753) (P<0.05). These findings indicate the importance of synergistic muscles and trunk muscles coactivation in eccentric and concentric hamstrings contractions. It could be important for early assessment of subjects with hamstring injury risk.
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Affiliation(s)
- Shideh Narouei
- Tehran University, School of Sport medicine Sciences, Tehran, Iran
| | - Atsushi Imai
- Waseda University, School of Sport Sciences, Tokorozawa, Japan
| | - Hiroshi Akuzawa
- Waseda University, School of Sport Sciences, Tokorozawa, Japan
| | - Kiyotaka Hasebe
- Waseda University, School of Sport Sciences, Tokorozawa, Japan
| | - Koji Kaneoka
- Waseda University, Faculty of Sport Sciences, Tokorozawa, Japan
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Roe M, Malone S, Delahunt E, Collins K, Gissane C, Persson UM, Murphy JC, Blake C. Eccentric knee flexor strength profiles of 341 elite male academy and senior Gaelic football players: Do body mass and previous hamstring injury impact performance? Phys Ther Sport 2018; 31:68-74. [PMID: 29503012 DOI: 10.1016/j.ptsp.2018.01.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 01/04/2018] [Accepted: 01/18/2018] [Indexed: 11/28/2022]
Abstract
OBJECTIVE Report eccentric knee flexor strength values of elite Gaelic football players from underage to adult level whilst examining the influence of body mass and previous hamstring injury. DESIGN Cross-sectional study. SETTING Team's training facility. PARTICIPANTS Elite Gaelic football players (n = 341) from under 14 years to senior age-grades were recruited from twelve teams. MAIN OUTCOME MEASURES Absolute (N) and relative (N·kg-1) eccentric hamstring strength as well as corresponding between-limb imbalances (%) were calculated for all players. RESULTS Mean maximum force was 329.4N (95% CI 319.5-340.2) per limb. No statistically significant differences were observed in relative force values (4.4 N ·kg-1, 95% CI 4.2-4.5) between age-groups. Body mass had moderate-to-large and weak associations with maximum force in youth (r = 0.597) and adult (r =0 .159) players, respectively. Overall 40% (95 CI 31.4-48.7) presented with a maximum strength between-limb imbalance >10%. Players with a hamstring injury had greater relative maximum force (9.3%, 95% CI 7.0-11.8; p > 0.05) and a 28% (95% CI 10.0-38.0) higher prevalence of between-limb imbalances ≥15% compared to their uninjured counterparts. CONCLUSIONS Overlapping strength profiles across age-groups, combined with greater strength in previously injured players, suggests difficulties for establishing cut-off thresholds associated with hamstring injury risk.
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Affiliation(s)
- Mark Roe
- School of Public Health, Physiotherapy and Sports Science, University College Dublin, Ireland.
| | - Shane Malone
- Gaelic Sports Research Centre, Department of Science, Institute of Technology Tallaght, Ireland; Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, UK
| | - Eamonn Delahunt
- School of Public Health, Physiotherapy and Sports Science, University College Dublin, Ireland; Institute for Sport and Health, University College Dublin, Ireland
| | - Kieran Collins
- Gaelic Sports Research Centre, Department of Science, Institute of Technology Tallaght, Ireland
| | - Conor Gissane
- School of Sport, Health and Applied Science, St Mary's University, UK
| | - Ulrik McCarthy Persson
- School of Public Health, Physiotherapy and Sports Science, University College Dublin, Ireland
| | | | - Catherine Blake
- School of Public Health, Physiotherapy and Sports Science, University College Dublin, Ireland
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