Post-eccentric Exercise Research Articles

Effect of L-Citrulline on Creatine Kinase MM (CK-MM) Isoenzymes in Mice: An In Vivo Study Focusing on Immunohistochemistry Analysis

Highlights:1. This study elucidates the effect of L-citrulline supplementation on creatine kinase MM (CK-MM) expression post-eccentric exercise, offering novel insights into its potential role in mitigating muscle damage.2. The findings demonstrate that L-citrulline administration significantly reduces CK-MM expression levels in skeletal muscle tissue, suggesting its therapeutic potential in enhancing muscle recovery and performance following exercise-induced damage.3. This study contributes valuable insights into the multifaceted benefits of L-citrulline supplementation for supporting overall muscle health and performance by identifying its protective effects under different mechanisms, including improved blood flow, antioxidant activity, enhanced mitochondrial function, and promotion of muscle protein synthesis. Abstract Eccentric exercise often induces muscle injuries in athletes, resulting in impaired performance and prolonged recovery time. Creatine kinase MM (CK-MM) is a biomarker for assessing muscle damage, with elevated levels indicating injury. L-citrulline, an amino acid, has shown promise in enhancing performance and reducing recovery time. However, its specific effect on CK-MM remains unclear. This study utilized immunohistochemistry analysis to investigate the effect of L-citrulline supplementation on CK-MM expression post-eccentric exercise in male BALB/c mice. This in vivo study was conducted with a post-test-only design. A total of 25 mice were divided into two control groups (normal/C1 and negative/C2) and three treatment groups (T1, T2, and T3), each containing five mice. The T1, T2, and T3 groups were daily administered 250, 500, and 1,000 mg/kg bw of L-citrulline for seven days, respectively. All mice, except the C1 group, performed a downhill running procedure. The CK-MM expression in skeletal muscle tissue post-eccentric exercise was assessed using immunohistochemistry analysis. The statistical analysis included the Shapiro-Wilk test for data distribution and the Kruskal-Wallis and Mann-Whitney post-hoc tests for significant differences (p<0.05). The results showed that CK-MM expression in the C2 group (91.00±2.24%) was significantly higher (p=0.008) than that of the C1 group (70.00±10.0%). Subsequently, the T1 (68.00±9.08%, p=0.008), T2 (72.00±7.58%, p=0.008), and T3 (67.00±9.75%, p=0.008) groups exhibited significantly lower expressions than the C2 group. These results were consistent with the role of CK-MM as a marker for muscle damage, and they indicated that L-citrulline might have a protective effect against muscle damage post-eccentric exercise. However, no significant differences were observed among the C1, T1, T2, and T3 groups. In conclusion, L-citrulline supplementation demonstrates promise in attenuating muscle damage following eccentric exercise, as evidenced by reduced CK-MM expression levels. These findings highlight the potential therapeutic role of L-citrulline in enhancing muscle recovery and performance.

Association between Serum Biomarkers of Muscle Damage after Isokinetic Eccentric Exercise in Trained Males and Females

Eccentric exercise is well-known to induce muscle damage, and biomarkers may be related to the magnitude of impact on muscle force and muscle soreness after exercise. However, this phenomenon still needs to be investigated in more detail. The present study aimed to analyze if a correlation between muscle force, soreness, and biomarkers after eccentric exercise exists in healthy, trained 11 males and females. Eleven volunteers with previous resistance training experience performed 6 x 10 maximal isokinetic eccentric contractions of the elbow flexors in the muscle performance laboratory up to 72 hours after exercise. Peak torque was measured by maximal voluntary isometric contractions (MVIC) and muscle soreness by visual analogic scale (VAS) before, 24h, 48h, and 72h after the isokinetic eccentric exercise protocol. A fluorescence immunoassay analyzer determined Myoglobin and C-reactive protein levels. The MVIC significantly decreased while muscle soreness increased 24h, 48h, and 72h post eccentric exercise. Myoglobin significantly increased 48h and 72h after exercise. Muscle soreness was inversely correlated with MVIC 24h, 48h, and 72h and positively correlated with myoglobin 48h and 72h after eccentric exercise. The myoglobin was not correlated with muscle force. No significant correlation between C-reactive protein and muscle soreness and MVIC was found. In conclusion, our data suggest that myoglobin could be a valuable biomarker to be assessed alongside exercise-induced muscle soreness.

Biceps brachii elastography in well-trained men post eccentric exercise-induced muscle damage.

Recent advancements in elastography techniques, specifically supersonic shearwave elastography (SWE), have enabled non-invasive assessment of muscle stiffness. However, there is limited research on the immediate and short-term effects of eccentric exercise-induced muscle damage (EIMD) in well-trained individuals. This study aimed to follow up on the effects of eccentric training on the biceps brachialis stiffness by supersonic shearwave imaging (SSI) as well as the soreness and elbow flexion maximal voluntary isometric contraction (MVIC), immediately post-intervention, at 10min, 48h, and 96h in well-trained men. Thirteen well-trained males participated in the study. Baseline measurements of elastography images, MVIC of the elbow flexors, and muscle soreness were obtained. The participants performed an eccentric exercise protocol (4 sets X 10 repetitions) on the dynamometer isokinetic and elastography measurements were repeated immediately post-exercise, at 10min, 48h, and 96h. Significant reductions in stiffness (measured by shear modulus (µ)) were observed immediately and at 10min post-exercise. MVIC exhibited significant reductions immediately after, 10min, and 48h compared to baseline measurements. Muscle soreness peaked at 48h, persisting until 96h. The BB stiffness and MVIC reduction immediately post-eccentric exercise in well-trained men, suggest the potential involvement of mechanical stress and sarcomere rupture. Trained individuals may exhibit a distinct response to EIMD compared to untrained individuals, highlighting the applicability of elastography in monitoring acute biomechanical changes following high-intensity exercise.

Effects of Percussive Massage Treatments on Symptoms Associated with Eccentric Exercise-Induced Muscle Damage.

Percussive massage (PM) is an emerging recovery treatment despite the lack of research on its effects post-eccentric exercise (post-EE). This study investigated the effects of PM treatments (immediately, 24, 48, and 72 h post-EE) on the maximal isometric torque (MIT), range of motion (ROM), and an 11-point numerical rating scale (NRS) of soreness of the nondominant arm's biceps brachii from 24-72 h post-EE. Seventeen untrained, college-aged subjects performed 60 eccentric elbow flexion actions with their nondominant arms. Nine received 1 minute of PM, versus eight who rested quietly (control [CON]). In order, NRS, ROM, and MIT (relative to body mass) were collected pre-eccentric exercise (pre-EE) and after treatment (AT) at 24, 48, and 72 h post-EE. NRS was also collected before treatment (BT). Electromyographic (EMG) and mechanomyographic (MMG) amplitudes were collected during the MIT and normalized to pre-EE. There were no interactions for MIT, EMG, or MMG, but there were interactions for ROM and NRS. For ROM, the PM group had higher values than the CON 24-72 h by ~6-8°, a faster return to pre-EE (PM: 48 h, CON: 72 h), and exceeded their pre-EE at 72 h by ~4°. The groups' NRS values did not differ BT 24-72 h; however, the PM group lowered their NRS from BT to AT within every visit by ~1 point per visit, which resulted in them having lower values than the CON from 24-72 h by ~2-3 points. Additionally, the PM group returned their NRS to pre-EE faster than the CON (PM: BT 72 h, CON: never). In conclusion, PM treatments may improve ROM without affecting isometric strength or muscle activation 24-72 h post-EE. Although the PM treatments did not enhance the recovery from delayed onset muscle soreness until 72 h, they consistently provided immediate, temporary relief when used 24-72 h post-EE.

A comparison of the effects of sheep's milk and cow's milk on recovery from eccentric exercise.

When consumed after eccentric exercise, cow's milk has been shown to improve recovery and alleviate symptoms of exercise induced muscle damage. Although currently less commercially available than cow's milk, sheep's milk may offer similar or greater benefits for recovery as it is higher in protein and energy; however, the effect of sheep's milk in any exercise context has not been explored. This study compared the effects of a sheep's milk beverage and a cow's milk beverage on recovery from strenuous eccentric exercise. Additionally, the effects of each beverage on satiety and gastrointestinal comfort were assessed. Ten healthy males completed baseline measures of perceived muscle soreness and maximal voluntary concentric, eccentric, and isometric quadriceps force of one leg before completing 200 maximal eccentric knee extensions on an isokinetic dynamometer. Measures were repeated 0.5, 24, 48 and 72 h post-eccentric exercise. After 0.5 h measures, participants consumed either 450 ml of chocolate flavored sheep's milk or chocolate flavored cow's milk. Following a washout period, participants completed a second trial on the contralateral leg and consumed the other beverage. Additionally, a satiety and gastrointestinal comfort questionnaire was completed before and after each beverage was consumed. Eccentric exercise brought about a significant decrease in muscle function over time (all P < 0.012). No difference between treatments (all P > 0.097) was found. Measures of muscle soreness increased over time (all P < 0.002), however no difference was observed between treatments (all P > 0.072). Only sheep's milk altered perceived satiety, however, only the response to "How full do you feel" differed between treatments (P = 0.04). The results of this study suggest that consuming sheep's milk may provide similar benefits as cow's milk when recovering from exercise-induced muscle damage. While these findings provide initial support for the use of sheep's milk in a muscle recovery context, further research is warranted to confirm these findings. Given its superior nutritional profile, greater impact on satiety and lower environment impact, sheep's milk may be a more efficient post-exercise recovery beverage, compared to cow's milk.

A Single Dose of Microencapsulated Cocoa Supplementation Does Not Speed up Muscle Force Recovery after Eccentric Exercise-Induced Muscle Damage: A Placebo-Controlled, Double-Blind, Crossover Study

Exercise-induced muscle damage is associated with symptoms such as inflammation, delayed-onset muscle soreness, and impaired muscle performance. The intake of cocoa polyphenols has been suggested to improve muscle recovery due to their antioxidant and anti-inflammatory capacity. However, their bioavailability presents a challenge. Therefore, food microencapsulation may be an alternative to protect polyphenols, ensuring their biological effects. This study aimed to investigate the effect of a single dose of microencapsulated cocoa on the changes in muscle damage markers after eccentric exercise. In this randomized, double-blind, crossover study, fourteen healthy volunteers with previous resistance training experience performed 6 × 10 maximal isokinetic eccentric contractions of their elbow flexors using an isokinetic dynamometer after ingesting 25 g of microencapsulated cocoa or placebo. Peak isometric torque was measured using maximal voluntary isometric contractions, and pain was measured using a visual analogic scale both before and 24 h, 48 h, and 72 h after the damage protocol. Plasma glutathione and malondialdehyde levels were measured using high-performance liquid chromatography, and concentrations of myoglobin and C-reactive protein were determined using a fluorescence immunoassay analyzer. Significant decreases were seen in the peak isometric torque and pain measures from pre- to 72 h post-eccentric exercise. A significant main effect for time was found only for plasma myoglobin at 2 h, 48 h, and 72 h, and for C-reactive protein at 2 h, compared to the pre-eccentric exercise values. No significant time-treatment effects were observed (all p &gt; 0.05). This study demonstrated that microencapsulated cocoa cannot improve muscle recovery after eccentric exercise, at least when a single dose is consumed.

The acute and repeated bout effects of multi-joint eccentric exercise on physical function and balance in older adults.

Eccentric muscle actions generate high levels of force at a low metabolic cost, making them a suitable training modality to combat age-related neuromuscular decline. The temporary muscle soreness associated with high intensity eccentric contractions may explain their limited use in clinical exercise prescription, however any discomfort is often alleviated after the initial bout (repeated bout effect). Therefore, the aims of the present study were to examine the acute and repeated bout effects of eccentric contractions on neuromuscular factors associated with the risk of falling in older adults. Balance, functional ability [timed up-and-go and sit-to-stand], and lower-limb maximal and explosive strength were measured in 13 participants (67.6 ± 4.9 year) pre- and post-eccentric exercise (0, 24, 48, and 72hr) in Bout 1 and 14days later in Bout 2. The eccentric exercise intervention was performed on an isokinetic unilateral stepper ergometer at 50% of maximal eccentric strength at 18 step‧min-1 per limb for 7min (126 steps per limb). Two-way repeated measures ANOVAs were conducted to identify any significant effects (P ≤ 0.05). Eccentric strength significantly decreased (-13%) in Bout 1 at 24hr post-exercise; no significant reduction was observed at any other time-point after Bout 1. No significant reductions occurred in static balance or functional ability at any time-point in either bout. Submaximal multi-joint eccentric exercise results in minimal disruption to neuromuscular function associated with falls in older adults after the initial bout.

Autonomic and cardiovascular responses on post-eccentric exercise recovery with blood flow restriction at different loads: Randomized controlled trial

Resistance training with blood flow restriction (BFR) has emerged as an method to gain strength and hypertrophy. However, the autonomic and cardiovascular repercussions of BFR and whether there is a dose-response relationship considering the load of the exercise when applied by means of eccentric contractions are not yet known. The objective was compare acute autonomic and cardiovascular responses following different loads of eccentric exercise with and without BFR. Sixty men were randomized into four groups: low and high load eccentric exercise (LLEE and HLEE); LLEE and HLEE with BFR (LLEE-BFR and HLEE-BFR). The participants underwent a single session of eccentric exercise for the quadriceps muscle in the dynamometer. Cardiovascular repercussions and heart rate variability were analyzed at baseline and for 60 min post-exercise. Variance analysis for a repeated measures model in the two-factor scheme was used with p<0.05. There were no interactions (group vs. moments) for any of the cardiovascular variables and autonomic indices analyzed, and there were no differences between groups. Differences between moments were observed only for the respiratory rate variable in the LLEE-BFR and HLEE-BFR in the first minute of recovery (21.13±5.00 and 21.25±4.55 irpm, respectively) in relation to the baseline (17.07±2.81 and 18.00±2.92 irpm, respectively). Increase in vagal indices was observed in the final moments of recovery for the LLEE-BFR and HLEE-BFR. In conclusion, eccentric exercise with or without BFR with different load was not enough to cause autonomic and cardiovascular imbalance in post-exercise recovery. Clinicaltrials.gov - NCT03942510

Effect of Dual Polyphenolic Ingredient on Muscle Injury and Performance: A Prospective, Double-Blind, Placebo-Controlled, Randomized, Interventional Study in Healthy Volunteers

Background: Eccentric exercise is a regular part of rehabilitation and sports training and to the unaccustomed, can cause muscle damage that presents as delayed soreness, strength and range of motion loss, swelling, and increased passive stiffness. These symptoms reduce exercise ability and might be harmful if exercise is further continued. In this study, we sought to test the efficacy of a proprietary dietary supplement, Gremin®, contains green coffee bean extract and curcumin in alleviating the severity of muscle damage and injury after standardized eccentric exercise. This study was a prospective, double-blind, placebo-controlled, randomized, interventional study. Sixteen healthy, moderately active, non-smoking volunteers with no known musculoskeletal pathology were enrolled. Mean differences within and between groups were assessed inferentially at each data collection point using t-tests for all outcome measures. Results: In this controlled study, the intake of Gremin® for 10 days resulted in a significant reduction in standardized measures of pain and tenderness at several post-eccentric exercise points compared to the placebo group. The Gremin® group had significantly reduced levels of plasma indicators of inflammation (C-reactive protein) and muscle damage (creatine kinase and lactate dehydrogenase), as well as standardized measures of pain and tenderness at several post-eccentric exercise time points, than the placebo group. Conclusions: Gremin® appears to be beneficial in accelerating the healing of acute muscle injury. Further studies with a larger sample size are warranted based on the current results.

The efficacy of intermittent pneumatic compression and negative pressure therapy on muscle function, soreness and serum indices of muscle damage: a randomized controlled trial

BackgroundThe study aimed to assess whether intermittent pneumatic compression (IPC) and intermittent negative pressure (INP) would attenuate the muscle damaging effects of eccentric exercise.MethodsForty-five healthy males were recruited. Immediately post, 24 and 48 h post eccentric exercise consisting of 100 drop jumps, volunteers randomly received 30-min sessions of intermittent pneumatic compression (IPC, n = 15) or intermittent negative pressure (INP, n = 15), or sham microcurrent (PT, n = 15). Creatine kinase (CK), lactate dehydrogenase (LDH), isokinetic muscle strength, soreness and active flexion of the knee joint were measured after every therapy session.ResultsNo significant intergroup differences were observed in biochemical or functional measurements. However, there was an increase in muscle soreness (P < 0.05), CK and LDH activity (P < 0.05), and a reduction in muscle strength (P < 0.05) and range of active knee flexion (P < 0.05).ConclusionsThe prescription of IPC and INP did not attenuate the reduction of markers to muscle function or pain perception up to 48 h after muscle damaging exercise. Future research should focus on the potential impact of treatment frequency and duration on muscle recovery.Trial registration The study was retrospectively registered in the Australian New Zealand Clinical Trials Registry (ANZCTR); The trial registration number: ACTRN12621001294842; date of registration: 24/09/2021.

Effects of different ischemic preconditioning occlusion pressures on muscle damage induced by eccentric exercise: a study protocol for a randomized controlled placebo clinical trial

IntroductionDue to its greater generation of muscle strength and less metabolic demand, eccentric exercise has been widely used in rehabilitation and for improving physical fitness. However, eccentric exercise can induce muscle damage by providing structural changes and reduced muscle function, so even with the protection caused by the repeated bout effect from eccentric exercise, it is necessary to seek alternatives to reduce this damage caused by stress. Thus, ischemic preconditioning could represent an aid to reduce the damage muscle or increase the protective effect caused by eccentric exercise.ObjectivesTo compare the effects of ischemic preconditioning, using different occlusion pressures, on acute and delayed responses to perceptual outcomes, markers of muscle damage, and performance in post-eccentric exercise recovery.MethodsA randomized controlled placebo clinical trial will be carried out with 80 healthy men aged 18 to 35 years who will be randomly divided into four groups: ischemic preconditioning using total occlusion pressure, ischemic preconditoning with 40% more than total occlusion pressure, placebo (10 mmHg), and control. The ischemic preconditioning protocol will consist of four cycles of ischemia and reperfusion of five minutes each. All groups will perform an eccentric exercise protocol, and assessments will be carried out before, immediately after, and 24, 48, 72, and 96 h after the end of the eccentric exercise to evaluate creatine kinase, blood lactate, perception of recovery using the Likert scale, being sequentially evaluated, pain by the visual analog scale, pain threshold using a pressure algometer, muscle thickness by ultrasound, muscle tone, stiffness and elasticity by myotonometry, vectors of cell integrity through electrical bioimpedance, and maximal voluntary isometric contraction using the isokinetic dynamometer. The trial was registered at ClinicalTrials.gov (NCT04420819).DiscussionThe present study aims to present an alternative technique to reduce muscle damage caused by eccentric exercise, which is easy to apply and low cost. If the benefits are proven, ischemic preconditioning could be used in any clinical practice that aims to minimize the damage caused by exercise, presenting an advance in the prescription of eccentric exercise and directly impacting on the results of post-exercise recovery.Trial registrationClinicalTrials.gov NCT04420819. Registered on 19 May 2020; Last update 24 March 2021.

Expression of tissue remodelling, inflammation- and angiogenesis-related factors after eccentric exercise in humans.

Eccentric exercise has been extensively used as a model to study the contraction-induced muscle damage and its consequent processes. This study aimed at examining molecular responses associated with tissue remodelling, inflammation and angiogenesis in skeletal muscle during the recovery period after eccentric exercise in humans. Ten healthy men performed 50 maximal eccentric muscle actions with the knee extensors and muscle biopsies were collected from the vastus lateralis before and 6h, 48h and 120h post eccentric exercise. Real Time-PCR was utilized to investigate alterations in gene expression of various tissue remodelling-, inflammation- and angiogenesis-related factors: uPA, uPA-R, TGF-β1, MMP-9, TNF-α, IL-6, IL-8, VEGF, VEGFR-2, HIF-1a, Ang-1, Ang-2 and Tie-2. The uPA/uPA-R system exhibited a similar time-expression pattern increasing 6h post exercise (p < 0.05), while the other tissue remodelling factors TGF-β1 and MMP-9 did not change significantly over time. Transcriptional responses of inflammatory factors TNF-α and IL-8 increased significantly and peaked 6h post eccentric exercise (p < 0.05), while IL-6 exhibited a similar, though not statistically significant, expression profile (p > 0.05). Similarly, the expression of angiopoietin receptor Tie-2 showed an early increase only at 6h after the completion of exercise (p < 0.05), while the other angiogenic factors failed to reach statistical significance due a high interindividual variability in the gene expression responses. The early transcriptional upregulation of tissue remodelling, inflammation- and angiogenesis-related factors post eccentric exercise may indicate the acute intramuscular activation of these processes functionally related to muscle damage-induced adaptation.

Altered Drop Jump Landing Biomechanics Following Eccentric Exercise-Induced Muscle Damage.

Limited research exists in the literature regarding the biomechanics of the jump-landing sequence in individuals that experience symptoms of muscle damage. The present study investigated the effects of knee localized muscle damage on sagittal plane landing biomechanics during drop vertical jump (DVJ). Thirteen regional level athletes performed five sets of 15 maximal eccentric voluntary contractions of the knee extensors of both legs at 60°/s. Pelvic and lower body kinematics and kinetics were measured pre- and 48 h post-eccentric exercise. The examination of muscle damage indicators included isometric torque, muscle soreness, and serum creatine kinase (CK) activity. The results revealed that all indicators changed significantly following eccentric exercise (p < 0.05). Peak knee and hip joint flexion as well as peak anterior pelvic tilt significantly increased, whereas vertical ground reaction force (GRF), internal knee extension moment, and knee joint stiffness significantly decreased during landing (p < 0.05). Therefore, the participants displayed a softer landing pattern following knee-localized eccentric exercise while being in a muscle-damaged state. This observation provides new insights on how the DVJ landing kinematics and kinetics alter to compensate the impaired function of the knee extensors following exercise-induced muscle damage (EIMD) and residual muscle soreness 48 h post-exercise.

Effect of Glutamine Supplement Administration on the Reduction of Muscular Fatigue Post-Eccentric Exercise

Eccentric activity can cause pain due to muscle damage and fatigue. Tired and damaged muscular state will degrade athletes' performance during a competition. Glutamine supplements are known to maintain plasma protein levels and can also improve muscle weakness due to inflammation that occurs after eccentric activity. The purpose of this study was to prove the effect of glutamine supplementation on the reduction of muscle fatigue after eccentric activity based on muscle strength and joint ROM. The subjects of this study were students of PJKR, IKIP Budi Utomo, who were randomly divided into 2 groups, the control group (K1) and treatment group (K2), each consisting of 22 respondents. The design of this research is randomized grsoup pre-test and post-test design. The eccentric activity performed was drop jumps on the bench with a height of 0.5 meters. Glutamine was administered orally after eccentric activity with a dose of 0.4 grams/kg BW in 450 ml water mineral 3 times (3 days). Measurement of Leg muscle strength was performed using Back and Leg Dynamometer by pulling with all the strength using leg muscles, whereas ROM measurements were measured using a goniometer performed on the knee joint in a passive way. The result of measurement obtained the mean of muscle strength of control group 63.7 ± 17.0 kg and treatment group 81.1 ± 17.0 kg at 72 hours. While result of ROM measurement obtained the mean of control group 124.3 ± 3.2 degrees and treatment group 131.7 ± 4.1 degrees at 72 hours. The analysis showed that glutamine administration in treatment group after eccentric activity increased leg muscle strength with p=0.000, and also increased knee joint ROM with p=0.000 at 72 hours after eccentric activity. In conclusion, glutamine administered with a dose of 0.4 gram/kg BW/day can increase leg muscle strength and knee joint ROM at 72 hours after eccentric activity.

Effectiveness of a combined New Zealand green-lipped mussel and Antarctic krill oil supplement on markers of exercise-induced muscle damage and inflammation in untrained men

Green-lipped mussel oil (PCSO-524®) has been shown to attenuate signs and symptoms of exercise-induced muscle damage (EIMD), and krill oil has been shown to have a protective effect against cytokine-induced tissue degradation. The purpose of this study was to compare the effects of PCSO-524® and ESPO-572® (75% PCSO-524® and 25% krill oil) on signs and symptoms of EIMD. Fifty-one untrained men consumed 600 mg/d of PCSO-524® (n = 24) or ESPO-572® (n = 27) for 26 d prior to and 72 h following a downhill running bout. Delayed onset muscle soreness (DOMS), pressure pain threshold, limb swelling, range of motion (ROM), isometric torque, and blood markers of inflammation and muscle damage were assessed at baseline, 24, 48 and 72 h post-eccentric exercise. ESPO-572® was ‘at least as good as’ PCSO-524® and both blends were superior (p < 0.05) to placebo in lessening the increase in DOMS at 24, 48, 72 h. ESPO-572® and PCSO-524® were protective against joint ROM loss compared to placebo (p < 0.05) at 48 and 72 h. Notably, at 24 and 48 h, joint ROM was higher in the ESPO-572® compared to the PCSO-524® group (p < 0.05). No differences between the two blends for the other markers were found. ESPO-572® is ‘at least as good’ as PCSO-524® in reducing markers of muscle damage and soreness following eccentric exercise and was superior to PCSO-524® in protecting against the loss in joint ROM during recovery. Our data support the use of ESPO-572®, a combination of green-lipped mussel and krill oil, in mitigating the deleterious effects of EIMD.

Effects of Whey and Pea Protein Supplementation on Post-Eccentric Exercise Muscle Damage: A Randomized Trial.

This randomized trial compared pea protein, whey protein, and water-only supplementation on muscle damage, inflammation, delayed onset of muscle soreness (DOMS), and physical fitness test performance during a 5-day period after a 90-min eccentric exercise bout in non-athletic non-obese males (n = 92, ages 18–55 years). The two protein sources (0.9 g protein/kg divided into three doses/day) were administered under double blind procedures. The eccentric exercise protocol induced significant muscle damage and soreness, and reduced bench press and 30-s Wingate performance. Whey protein supplementation significantly attenuated post-exercise blood levels for biomarkers of muscle damage compared to water-only, with large effect sizes for creatine kinase and myoglobin during the fourth and fifth days of recovery (Cohen’s d > 0.80); pea protein versus water supplementation had an intermediate non-significant effect (Cohen’s d < 0.50); and no significant differences between whey and pea protein were found. Whey and pea protein compared to water supplementation had no significant effects on post-exercise DOMS and the fitness tests. In conclusion, high intake of whey protein for 5 days after intensive eccentric exercise mitigated the efflux of muscle damage biomarkers, with the intake of pea protein having an intermediate effect.

The Effects Of Contrast With Compression Therapy On Muscle Recovery Post Exercise

Intense eccentric exercise causes muscle damage that leads to a decrease in subsequent performance. Accelerating muscle recovery between bouts of exercise minimizes the risk of injury and is essential for optimal athletic competitive performance. PURPOSE: The purpose of this study was to determine if the contrast with compression (CwC) therapy proprietary device by Solid State Inc was able to improve muscle recovery post intense eccentric exercise. METHODS: Ten physically active men (age = 21.3+2.1 years; height = 182 +8.5cms; weight = 88 + 19.5kg; body fat = 17.2+7%) completed two separate single-arm elbow flexor workouts on an isokinetic dynamometer. After one workout each participant received contrast with compression (CwC) therapy immediately after, 24h and 48h after the workout. After the other workout the same person received no treatment(CON). Post-exercise recovery of selected characteristics were measured at 1h, 24h, 48h and 72h. Comparisons were made between the CwC and CON groups using a Mixed Model ANOVA with repeated measures to identify time effects and an ANCOVA was used to identify interaction effects. A Bonferroni post-hoc test was used to assess timepoint differences in between interventions in recovery post eccentric exercise. A p≤0.05 was used for all analysis. RESULTS: CwC therapy post exercise resulted in a significantly faster recovery rate of strength and power to baseline levels (p=0.00) as well as a greater recovery of overall relative strength (p=0.004). Treatment with CwC significantly suppressed the post-exercise inflammatory response (p=0.05) and significantly reduced the secondary muscle damage response as measured by levels of Creatine Kinase post exercise. CwC therapy also resulted in a significantly quicker recovery of the maximal elbow flexion range of motion (p=0.00) within the hour post exercise. Lastly, participants experienced significantly less soreness 48 hours and 72 hours post-exercise with CwC therapy. CONCLUSION: Contrast with compression therapy significantly increases the recovery rate of muscle strength and power post eccentric exercise. CwC is also effective at reducing exercise associated muscle damage, delayed onset muscle soreness and mitigates the loss of range of motion post intense exercise.

Effectiveness Of Two Different Forms Of Marine Oil On Muscle Soreness Following Eccentric Exercise

PURPOSE: We have previously shown1 that four weeks of supplementation with PCSO-524®, a marine lipid fraction of the New Zealand green-lipped mussel (Perna canaliculus), rich in omega-3 fatty acids, attenuates muscle damage and delayed onset muscle soreness (DOMS) following eccentric exercise in untrained men. The present study sought to determine if a blend of 75% PCSO-524® and 25% krill oil (ESPO-572®) will be ‘at least as good’ as PCSO-524® in attenuating DOMS and functional indices of muscle damage during recovery from muscle damaging exercise in untrained men. METHODS: This study was conducted as a randomized, parallel group, double-blind non-inferiority trial. Fifty-one untrained men were randomly assigned to consume 600 mg·d-1 (4 capsules) of either PCSO-524® (n=24) or ESPO-572® (n=27) for 26 d prior to muscle damaging exercise (downhill running), and continued for 72 h following exercise. DOMS, pressure pain threshold (PPT), limb swelling, knee extensor range of motion (ROM), and isometric torque (MVC), were assessed at baseline following supplementation before eccentric exercise, and at 24, 28 and 72 h post-eccentric exercise. For data analysis purposes we included placebo group (olive oil) (n=16) data generated from our previously published work1 that followed an identical study design. RESULTS: ESPO-572® is ‘at least as good’ as PCSO-524®, but both blends were significantly better (p<0.05) than placebo, in reducing DOMS at 24, 48, 72 h following muscle damaging exercise. At 24 and 48 h following the eccentric exercise bout ESPO-572® significantly increased (p<0.05) ROM compared to PCSO-524®. Compared to placebo, ESPO-572® significantly improved (p<0.05) ROM at 24, 48 and 72 h, while PCSO-524® significantly increased (p<0.05) ROM at 48 and 72 h during recovery. There were no significant differences (p<0.05) between ESPO-572® and PCSO-524® for PPT, limb swelling and MVC during recovery from muscle damaging exercise. CONCLUSION: These data suggest that ESPO-572® may represent a useful therapeutic agent for attenuating muscle soreness following eccentric-type exercise in untrained men. 1Mickleborough et al. Journal of the International Society of Sports Nutrition (2015) 12:10. Supported by a grant from Pharmalink International Ltd, Hong Kong.

BILATERAL SENSORY DEFICITS AND WIDESPREAD HYPERALGESIA OCCUR FOLLOWING INDUCED DELAYED ONSET MUSCLE SORENESS OF THE QUADRICEPS

Unaccustomed eccentric exercise during sport or training may lead to delayed onset muscle soreness (DOMS), which has been demonstrated to influence postural control, potentially resulting in further injury. Afferent sensory input is critical to effective postural control, but little is known about somatosensory changes at the knee following induction of DOMS of the quadriceps muscle. The 'soreness' or hyperalgesia associated with DOMS has been postulated to occur because of damage to/inflammation of the exercised muscle, however, effects on central nociceptive mechanisms, which are known to induce altered postural responses, have been less studied. It was hypothesized that DOMS of the quadriceps muscle would result in widespread hyperalgesia and hypoesthesia at the knee. Therefore, the purpose of this study was to investigate the effects of DOMS on knee somatosensory changes in asymptomatic healthy participants. Quasi-experimental cohort study. Thirty participants (15 males and 15 females) took part in the study. Eccentric exercise consisted of 10 sets of 10 maximum eccentric quadriceps contractions performed with the dominant knee. Outcome measures consisted of pain intensity (Visual Analog Scale), pressure pain threshold (PPT), vibration perception threshold (VPT) and proprioception, measured via threshold to detection of passive motion (TDPM) at the knee, at three different assessment time points: (1) pre-eccentric exercise; (2) immediately and (3) 48 hours post-eccentric exercise. Not surprisingly, pain intensity increased and PPT of the vastus medialis and rectus femoris muscles decreased (hyperalgesia) immediately post-exercise on the exercised limb. However, at 48 hours, hyperalgesia was demonstrated at other lower extremity muscles, including bilaterally at the tibialis anterior muscles, and also at the hand. Evidence of hypoesthesia was also demonstrated. VPT and TDPM increased (worsened) ipsilaterally both immediately and 48 hours after exercise, and TDPM increased bilaterally at 48 hours. Females demonstrated greater impairment in TDPM than males at 48 hours. Expanding distribution of hyperalgesia, ipsilaterally impaired VPT and bilaterally impaired proprioception were demonstrated in the presence of DOMS. Inflammation from unaccustomed eccentric exercise may induce neuroplastic changes in nociceptive pathways resulting in wider distribution of pain and hypoesthesia. Futures studies examining the effect of DOMS related somatosensory changes on postural control may be warranted. 3.

Effect of Glutamine Supplement Administration on the Reduction of Muscular Fatigue Post-Eccentric Exercise

Eccentric activity can cause pain due to muscle damage and fatigue. Tired and damaged muscular state will degrade athletes' performance during a competition. Glutamine supplements are known to maintain plasma protein levels and can also improve muscle weakness due to inflammation that occurs after eccentric activity. The purpose of this study was to prove the effect of glutamine supplementation on the reduction of muscle fatigue after eccentric activity based on muscle strength and joint ROM. The subjects of this study were students of PJKR, IKIP Budi Utomo, who were randomly divided into 2 groups, the control group (K1) and treatment group (K2), each consisting of 22 respondents. The design of this research is randomized grsoup pre-test and post-test design. The eccentric activity performed was drop jumps on the bench with a height of 0.5 meters. Glutamine was administered orally after eccentric activity with a dose of 0.4 grams/kg BW in 450 ml water mineral 3 times (3 days). Measurement of Leg muscle strength was performed using Back and Leg Dynamometer by pulling with all the strength using leg muscles, whereas ROM measurements were measured using a goniometer performed on the knee joint in a passive way. The result of measurement obtained the mean of muscle strength of control group 63.7 ± 17.0 kg and treatment group 81.1 ± 17.0 kg at 72 hours. While result of ROM measurement obtained the mean of control group 124.3 ± 3.2 degrees and treatment group 131.7 ± 4.1 degrees at 72 hours. The analysis showed that glutamine administration in treatment group after eccentric activity increased leg muscle strength with p=0.000, and also increased knee joint ROM with p=0.000 at 72 hours after eccentric activity. In conclusion, glutamine administered with a dose of 0.4 gram/kg BW/day can increase leg muscle strength and knee joint ROM at 72 hours after eccentric activity.