Eccentric Exercise Research Articles

The Effects of Nordic Hamstring Exercise on Performance and Injury in the Lower Extremities: An Umbrella Review.

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.

Acute Effects of Combined and Distinctive Stretching, Foam Rolling, and Eccentric Exercise in Young Men with Hamstring Tightness

Acute Effects of Combined and Distinctive Stretching, Foam Rolling, and Eccentric Exercise in Young Men with Hamstring Tightness

Optimizing recovery: how PNF stretching and ice massage alleviate markers of DOMS?

Delayed onset muscle soreness (DOMS) is a common problem for both trained or untrained individuals that develop after eccentric or unaccustomed exercise. The large number of cases of DOMS and the varying results of research related to the prevention and treatment of DOMS, imply the importance of research in the effective DOMS prevention. The aim of this research was to investigate the post-exercise effects of combination Proprioceptive Neuromuscular Facilitation (PNF) stretching and ice massage on markers of exercise-induced muscle damage (DOMS). Thirty-nine subjects between the ages of 15 to 17 were randomly assigned to either the experimental or control groups. Subjects performed circuit training exercise-induced DOMS. The experimental group underwent 18 minutes of PNF stretching and 16 minutes of ice massage, which was given 2 hours after exercise. The control group did not receive any treatment. DOMS parameters (muscle soreness, creatine kinase/CK, aspartate aminotransferase/AST, neutrophil) and lower extremity functional scale (LEFS) were assessed at 0 and 24 hours after exercise-induced DOMS. The parametric and non-parametric different tests was used in data analysis. The experimental groups showed a reduction in DOMS symptoms in the form of less muscle soreness and AST, better LEFS compared to control groups (p<0.05), but not for creatine kinase and neutrophils (p>0.05) which is an indicator of tissue damage. In conclusion, the combination of postexercise PNF stretching and ice massage was effective in reducing the severity of DOMS, but it was not able to prevent DOMS. Keywords: PNF Stretching, Ice Massage, DOMS, Creatine Kinase, Muscle Recovery, Exercise-induced Muscle Damage

Comparative effects of myofascial release with and without eccentric resistance on pain, range of motion, and functional disability in patients with Achilles tendinopathy

BackgroundThe ankle is one of the most commonly injured areas in people with active and sedentary lives. Achilles tendinopathy (AT) is characterized by pain and stiffness that limits daily living work. Myofascial release and eccentric training are believed to improve soft tissue circulation, strength, pain, ROM, and function. ObjectiveTo compare the effects of myofascial release with and without eccentric resistance on pain, range of motion, and functional disability in patients with AT. MethodologyThis randomized clinical trial was conducted with a sample of 72 participants selected via a convenient sampling technique. Participants were divided into two groups, Group A was given myofascial release therapy, and Group B was given myofascial release with eccentric resistance. Numeric Pain Rating Scale (NPRS), Goniometer, and Foot ankle disability index (FADI) were outcome measure tools for pain, range of motion, and functional disability. The assessment was done at baseline, 2nd and 4th week. Mann-Whitney U Test and Friedman's ANOVA were applied to find between-group and within-group differences. P-value was set at ≤0.05. ResultsThere was a significant difference in pain (p = 0.03), plantarflexion ROM (p = 0.008), and functional disability (p = 0.02) between the two groups. However, no significant difference was observed in dorsiflexion (p = 0.06). Within-group differences were also significant (p < 0.05). ConclusionIt is concluded that myofascial release with eccentric resistance was more effective than myofascial release without eccentric resistance in improving pain, range of motion, and functional disability in Achilles tendinopathy.

Effects of muscle fatigue on quadriceps muscle performance in healthy amateur soccer players

IntroductionQuadriceps femoris muscle (QFM) fatigue has a detrimental impact on athlete performance. Therefore, it is crucial to evaluate various performance parameters under fatigued conditions. This study aimed to assess the performance of the QFM during both concentric and eccentric contractions before and after fatigue in the lower extremities of healthy amateur soccer players. MethodTwenty-four healthy amateur soccer players performed three consecutive knee extension and flexion movements concentrically and eccentrically at a velocity of 120°/s with maximum effort, using a Biodex dynamometer. Fatigue was induced by a protocol involving repetitive concentric knee extension and flexion movements at 120°/s, with a load of 50% of maximal voluntary isometric contraction (MVIC) of the QFM until its moment declined to 50% of MVIC. Separate 2-way analyses of variance were conducted to assess the influence of contraction and fatigue on various isokinetic parameters. ResultsNo significant interaction effect between contraction and fatigue was observed for any of the parameters. There was a significant main effect of fatigue on average power for both lower extremities. However, no significant main effect of fatigue was observed for normalized peak moment, angle of peak moment, moment at 0.2s, total work, acceleration, and deceleration times. In contrast, significant main effects of contraction were noted for normalized peak moment, moment at 0.2s, average power, acceleration, and deceleration times in both lower extremities. ConclusionAverage power appeared as the most sensitive performance parameter to fatigue. To enhance QFM performance, emphasizing eccentric exercises during training and conditioning programs could be beneficial for athletes.

Outcome of Isolated Eccentric Exercise Therapy in Sports Persons with Rotator Cuff Tendinopathy

Outcome of Isolated Eccentric Exercise Therapy in Sports Persons with Rotator Cuff Tendinopathy

Effect of Microencapsulated Cocoa Polyphenols on Macro- and Microvascular Function after Eccentric Exercise

Background: Evidence has demonstrated that non-habitual exercise, such as eccentric exercise, can increase reactive oxygen species and induce endothelial dysfunction, which plays a central role in the development of cardiovascular disease. Polyphenol-rich foods, such as cocoa, have been widely investigated in vascular function due to their antioxidant effect. Aims: The goal of this study was to evaluate the impact of microencapsulated cocoa (MC) polyphenols in the flow-mediated dilation (FMD) response and forearm muscle oxygenation (StO2) parameters after an eccentric exercise. Methods: Thirteen physically active adults were enrolled in a randomized, double-blind, and crossover study. FMD and StO2 were evaluated before and after 24 h, 48 h, and 72 h of eccentric exercise and MC or placebo supplementation. Results: No significant difference in FMD response and StO2 parameters was observed after MC and placebo (p &gt; 0.05). Conclusions: A single dose of MC did not change FMD and muscle StO2 parameters after eccentric exercise in healthy individuals.

Bioimpedance analysis for identifying new indicators of exercise-induced muscle damage

A noninvasive, immediate, and convenient method for assessing muscle tissue status during exercise-induced muscle damage (EIMD) has not been established. This study was designed to assess and determine parameters suitable for measuring EIMD after eccentric exercise, using multi-frequency bioimpedance analysis (BIA). Thirty-five young male participants performed dumbbell exercises with their left arm, and their BIA parameters were measured at various time points up to 168 h post exercise using a multi-frequency BIA device. At all-time points, intra and extracellular water content was greater in the left arm than in the right arm, whereas the impedance, reactance, resistance, and phase angle were lower in the left arm than in the right arm. Established EIMD indices, such as maximal isometric voluntary contraction, were measured and used in correlational analyses. Only reactance was correlated with biomarkers, indicating muscle damage (r = − 0.56 to − 0.49). Furthermore, reactance was found to correlate well with indirect indicators of EIMD, suggesting that it may be a suitable marker for evaluating EIMD. However, the relationship with the limited evaluation indices employed in this study is constrained. Future studies should investigate the correlation between reactance and direct damage indicators, such as structural damage, observed in biopsies.

The relationship between sustained hamstring pain and reorganisation of somatosensory representations: a randomised, controlled study.

Recurrent hamstring injuries are highly prevalent amongst sporting populations. It has been hypothesised that pain from an initial hamstring injury may induce reorganisation of somatosensory representations that could contribute to reinjury. However, because of the cross-sectional nature of existing research, it remains unknown whether somatosensory changes are a cause or effect of pain or if they are driven by other potentially confounding factors. Here, we explored the effect of experimentally induced sustained hamstring pain on tasks that interrogate somatosensory and spatial representations. Fifty healthy participants were randomly allocated to an experimental group that performed an eccentric exercise protocol on the right hamstring to induce delayed onset muscle soreness or a control group performing a repetition-matched concentric exercise protocol. The tactile cortical representation was assessed using two-point discrimination and tactile localisation, whereas the proprioceptive representation was assessed using a left-right judgement task. Peripersonal spatial representations were assessed using an auditory localisation task. Assessments were performed at baseline and day 2. No between-group differences in tactile acuity were observed. However, improvements in left-right judgments and worsening of auditory localisation occurred in the experimental group compared with the control group. This study provides preliminary evidence showing that somatosensory changes occur in response to sustained hamstring pain. Experimentally induced, sustained hamstring pain elicited enhancements in proprioceptive processing and deficits in peripersonal spatial processing, suggesting a shift in the allocation of attentional resources from the external (peripersonal) to internal (body) environment. These findings may hold important implications for reinjury risk and rehabilitation following hamstring pain.

A Comparison of Force Production in Eccentric Hamstring Exercises

A Comparison of Force Production in Eccentric Hamstring Exercises

Impact of Eccentric versus Concentric Cycling Exercise on Neuromuscular Fatigue and Muscle Damage in Breast Cancer Patients.

This study investigated the magnitude and etiology of neuromuscular fatigue and muscle damage induced by eccentric cycling compared with conventional concentric cycling in patients with breast cancer. After a gradual familiarization protocol for eccentric cycling, nine patients with early-stage breast cancer performed three cycling sessions in eccentric or concentric mode. The eccentric cycling session (ECC) was compared with concentric cycling sessions matched for power output (CON power ; 80% of concentric peak power output, 95 ± 23 W) or oxygen uptake ( ; 10 ± 2 mL·min·kg -1 ). Preexercise to postexercise changes (30-s through 10-min recovery) in knee extensor maximal voluntary contraction force (MVC), voluntary activation, and quadriceps potentiated twitch force ( Qtw ) were quantified to determine global, central, and peripheral fatigue, respectively. Creatine kinase and lactate dehydrogenase activities were measured in the plasma before and 24 h after exercise as markers of muscle damage. Compared with CON power (-11% ± 9%) and (-5% ± 5%), the ECC session resulted in a greater decrease in MVC (-25% ± 12%) postexercise ( P < 0.001). Voluntary activation decreased only in ECC (-9% ± 6% postexercise, P < 0.001). The decrease in Qtw was similar postexercise between ECC and CON power (-39% ± 21% and -40% ± 16%, P > 0.99) but lower in ( P < 0.001). The CON power session resulted in twofold greater compared with the ECC and sessions ( P < 0.001). No change in creatine kinase or lactate dehydrogenase activity was reported from preexercise to 24 h postexercise. The ECC session induced greater neuromuscular fatigue compared with the concentric cycling sessions without generating severe muscle damage. ECC is a promising exercise modality for counteracting neuromuscular maladaptation in patients with breast cancer.

Eccentric exercise before a 90min exposure at 24,000ft increases decompression strain depending on body region but not total muscle mass recruited.

Eccentric upper-body exercise performed 24h prior to high-altitude decompression has previously been shown to aggravate venous gas emboli (VGE) load. Yet, it is unclear whether increasing the muscle mass recruited (i.e., upper vs. whole-body) during eccentric exercise would exacerbate the decompression strain. Accordingly, this study aimed to investigate whether the total muscle mass recruited during eccentric exercise influences the decompression strain. Eleven male participants were exposed to a simulated altitude of 24,000ft for 90min on three separate occasions. Twenty-four hours before each exposure, participants performed one of the following protocols: (i) eccentric whole-body exercise (ECCw; squats and arm-cycling exercise), (ii) eccentric upper-body exercise (ECCu; arm-cycling), or (iii) no exercise (control). Delayed onset muscle soreness (DOMS) and isometric strength were evaluated before and after each exercise intervention. VGE load was evaluated at rest and after knee- and arm-flex provocations using the 6-graded Eftedal-Brubakk scale. Knee extensor (-20±14%, P=0.001) but not elbow flexor (-12±18%, P=0.152) isometric strength was reduced 24h after ECCw. ECCu reduced elbow flexor isometric strength at 24h post-exercise (-18±10%, P<0.001). Elbow flexor DOMS was higher in the ECCu (median 6) compared with ECCw (5, P=0.035). VGE scores were higher following arm-flex provocations in the ECCu (median (range), 3 (0-4)) compared with ECCw (2 (0-3), P=0.039) and control (0 (0-2), P=0.011), and in ECCw compared with control (P=0.023). VGE were detected earlier in ECCu (13±20min) compared with control (60±38min, P=0.021), while no differences were noted between ECCw (18±30min) and control or ECCu. Eccentric exercise increased the decompression strain compared with control. The VGE load varied depending on the body region but not the total muscle mass recruited. HIGHLIGHTS: What is the central question of this study? Does exercise-induced muscle damage (EIMD) resulting from eccentric exercise influence the presence of venous gas emboli (VGE) during a 90min continuous exposure at 24,000ft? What is the main finding and its importance? EIMD led to an earlier manifestation and greater VGE load compared with control. However, the decompression strain was dependent on the body region but not the total muscle mass recruited.

Combined regenerative rehabilitation improves recovery following volumetric muscle loss injury in a rat model.

Volumetric muscle loss (VML) injury causes irreversible deficits in muscle mass and function, often resulting in permanent disability. The current standard of care is physical therapy, but it is limited in mitigating functional deficits. We have previously optimized a rehabilitation technique using electrically stimulated eccentric contraction training (EST) that improved muscle mass, strength, and size in VML-injured rats. A biosponge scaffold composed of extracellular matrix proteins has previously enhanced muscle function postVML. This study aimed to determine whether combining a regenerative therapy (i.e., biosponge) with a novel rehabilitation technique (i.e., EST) could enhance recovery in a rat model of VML. A VML defect was created by removing ~20% of muscle mass from the tibialis anterior muscle in adult male Lewis rats. Experimental groups included VML-injured rats treated with biosponge with EST or biosponge alone (n = 6/group). EST was implemented 2 weeks postinjury at 150 Hz and was continued for 4 weeks. A linear increase in eccentric torque over 4 weeks showed the adaptability of the VML-injured muscle to EST. Combining biosponge with EST improved peak isometric torque by ~52% compared with biosponge treatment alone at 6 weeks postinjury. Application of EST increased MyoD gene expression and the percentage of large (>2000 μm2) type 2B myofibers but reduced fibrotic tissue deposition in VML-injured muscles. Together, these changes may provide the basis for improved torque production. This study demonstrates the potential for combined regenerative and rehabilitative therapy to improve muscle recovery following VML.

Eccentric training vs muscle energy technique in adjunct to low-level laser therapy for lateral epicondylitis

Eccentric training vs muscle energy technique in adjunct to low-level laser therapy for lateral epicondylitis

Functionality and jump performance in patellar tendinopathy with the application of three different treatments

ObjectivesThe aim is to assess performance characteristics in jumps and functionality in participants with patellar tendinopathy and compare changes with various tendinopathy treatments in the short and medium term. As a secondary objective, the study aims to verify the relationship between changes in knee functionality assessed by the VISA-P and jump capacity in the different treatment groups. DesignA double-blinded randomized controlled trial. MethodsRecruitment was conducted at sport clubs, with 48 participants with patellar tendinopathy included in the study. Participants were randomized into groups: dry needling (DN), percutaneous electrolysis (PNE), and sham needling as the control group (CG), all combined with eccentric exercise (EE). Functionality and performance during jumps, including squat jump (SJ) and counter movement jump (CMJ), were assessed. ResultsSignificant differences were found in functionality between the pre-test and post-test evaluations, as well as between the pre-test and follow-up evaluations, in all three groups (p < 0.001). The DN group experienced an improvement in eccentric power (p = 0.021). A moderate correlation was found between the pre-test and post-test changes in functionality and SJ maximum concentric force (r = 0.63, p < 0.01, CI: 0.1; 0.8), CMJ maximum concentric force (r = 0.52, p = 0.05, CI: −0.01; 0.8), and CMJ eccentric power in the DN group (r = 0.63, p = 0.01, CI: 0.1; 0.8). ConclusionsEccentric exercise could be effective in improving functionality in patellar tendinopathy and DN could improve eccentric power in jumps performance. Moreover, the DN group experienced an increase in functionality that correlated with the improvements found in jump performance in eccentric power and concentric strength.

Pre-exercise cryotherapy reduces myoglobin and creatine kinase levels after eccentric muscle stress in young women.

Introduction: The aim of this study was to investigate the effect of pre-exercise whole-body cryotherapy (WBC) on muscle damage indicators following eccentric treadmill exercise in young women. Methods: Twenty-seven participants underwent two 1-h downhill treadmill runs, replicating 60% of their maximal oxygen uptake, with a 4-week intermission for recovery and treatment application. In this intermission, one group underwent 20 sessions of WBC, delivered five times a week at -120°C for 3min each, while the comparison group received no such treatment. Markers of muscle injury-serum myoglobin concentration, creatine kinase and lactate dehydrogenase activity and also uric acid, and cell-free DNA concentration-were measured before and after downhill runs. Results: The study observed a notable reduction in post-exercise myoglobin and CK levels in the WBC group after the second running session. Discussion: The results suggest that WBC can have a protective effects against muscle damage resulting from eccentric exercise.

The effect of individualised post-exercise blood flow restriction on recovery following strenuous resistance exercise: A randomised controlled trial

ABSTRACT The purpose was to clarify the effect of individualised post-exercise blood flow restriction (PE-BFR) on measures of recovery following strenuous resistance exercise. Twenty resistance-trained adults were randomised to a PE-BFR or control (CON) group and completed a fatigue protocol of five sets of 10 repetitions of maximal intensity concentric and eccentric seated knee extension exercise. Participants then lied supine with cuffs applied to the upper thigh and intermittently inflated to 80% limb occlusion pressure (PE-BFR) or 20 mmHg (CON) for 30 min (3 × 5 min per leg). Peak torque (PT), time-to-peak torque (TTP), countermovement jump height (CMJ), muscle soreness (DOMS) and perceived recovery (PR) were measured pre-fatigue, immediately post-fatigue and at 1, 24, 48 and 72 h post-fatigue. Using a linear mixed-effect model, PE-BFR was found to have greater recovery of CMJ at 48 h (mean difference [MD]=-2.8, 95% confidence interval [CI] −5.1, 0.5, p = 0.019), lower DOMS at 48 (MD = 3.0, 95% CI 1.2, 4.9, p = 0.001) and 72 h (MD = 1.95, 95% CI −1.2, 1.5, p = 0.038) and higher PR scores at 24 (MD = −1.7, 95% CI −3.4, −0.1, p = 0.038), 48 (MD = −3.1, 95% CI −4.8, −1.5, p < 0.001) and 72 h (MD = −2.2, 95% CI −3.8, −0.5, p = 0.011). These findings suggest that individualised PE-BFR accelerates recovery after strenuous exercise.

Entrenamiento excéntrico un aliado en la prevenciónde lesiones y en la mejora del rendimiento deportivo.

The training focuses on the elongation phase of muscle actions. Several investigations pointed out eccentric training as an injurious method due to the generation of muscle soreness (DOMS) 24, 48 and even 72 hours post-training. Nowadays, this type of contractions has been the focus of further studies and has shown positive effects in the increase of muscular strength and power, besides being a protective factor in the prevention of injuries. This letter to the editor is intended to show updated evidence regarding the role of eccentric exercise proposing four levels of work according to the literature detailing series, repetitions and percentages of 1RM according to the objective and level of the subject or athlete. This information is useful for the same athletes and/or trainers so that they can use this type of exercises in their training programs according to the age and sex of the people.

The effects of the addition of Mulligan mobilization with movement to exercise on elbow pain and function associated with lateral elbow tendinopathy

BackgroundMulligan mobilization with movement (MWM) and eccentric exercise (EE) have been shown to be effective for the treatment of chronic lateral elbow tendinopathy (LET). However, the addition of MWM to EE effects on LET remained unknown. The objective of the study was to determine the effects of adding of Mulligan mobilization with movement to eccentric exercise for the treatment of LET. MethodsIn this quasi-experimental study, thirty participants with unilateral LET were assigned into two groups: 15 in MWM (received MWM + EE) (7 M and 8 F, mean age 36.8 ± 8.3 years) and 15 in EE (9 M and 6 F, mean age 46 ± 8.1 years). Both groups received education about painful activities and eccentric exercise, while the MWM group received MWM with the same eccentric exercise as the EE group. The visual analog scale (VAS) and the patient-rated tennis elbow evaluation (PRTEE) were used to assess pain and upper limb function, respectively, at baseline and at the end of 4 weeks. The data was analyzed using an independent t-test and a paired t-test. ResultsThere was no significant difference (p > 0.05) between groups at baseline. At the end of 4 weeks, significant and clinically meaningful improvements in pain and function were observed for both groups (p < 0.001); however, MWM group showed much better results in VAS (p < 0.001, d = 1.3) and PRTEE (p < 0.001, d = 5.2) ConclusionThis study showed that adding MWM to eccentric exercise resulted in enhanced pain reduction and improved function of the upper limb.

High Velocity Passive Stretching Mimics Eccentric Exercise in Cerebral Palsy and May Be Used to Increase Spastic Muscle Fascicle Length.

Muscle fascicles are shorter and stiffer than normal in spastic Cerebral Palsy (CP). Increasing fascicle length (FL) has been attempted in CP, the outcomes of which have been unsatisfactory. In healthy muscles, FL can be increased using eccentric exercise at high velocities (ECC). Three conditions are possibly met during such ECC: muscle micro-damage, positive fascicle strain, and momentary muscle deactivation during lengthening. Participants with and without CP underwent a single bout of passive stretching at (appropriately) high velocities using isokinetic dynamometry, during which we examined muscle and fascicle behaviour. Vastus lateralis (VL) FL change was measured using ultrasonography and showed positive fascicle strain. Measures of muscle creatine kinase were used to establish whether micro-damage occurred in response to stretching, but the results did not confirm damage in either group. Vastus medialis (VM) and biceps femoris muscle activity were measured using electromyography in those with CP. Results supported momentary spastic muscle deactivation during lengthening: all participants experienced at least one epoch (60 ms) of increased activation followed by activation inhibition/deactivation of the VM during knee flexion. We argue that high-velocity passive stretching in CP provides a movement context which mimics ECC and could be used to increase spastic FL with training.