Nonpharmacological Therapies for Musculoskeletal Injury in Military Personnel: A Systematic Review/Meta-Analysis.

INTRODUCTION: Musculoskeletal (MSK) injury is an inherent risk for military personnel that can potentially impact job performance, productivity, and military readiness. Evidence is needed to show the efficacy of nonpharmacological, self-managed therapies to reduce MSK symptoms at common injury sites that are feasible for use during expeditionary operations and home stations. This systematic review and meta-analysis identified, summarized, and synthesized available evidence from randomized and non-randomized trials on the effectiveness of self-managed, home-use therapies to improve pain, muscle strength, and physical performance in military personnel with MSK injuries, when compared to controls. METHODS: The electronic databases of MEDLINE ALL Ovid, Embase.com, Cochrane Library, Scopus, Clinicaltrial.gov, and CINAHL Complete via EBSCO were systematically searched for relevant reports published in English. Utilizing the Covidence platform and consistent with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, multiple reviewers, using pre-determined data fields, screened for eligibility, assessed risk of bias (RoB), and performed data extraction. Evaluation of treatment effectiveness was determined using multilevel mixed-effects meta-analysis. RESULTS: The database and register search yielded 1,643 reports that were screened for eligibility. After screening of titles/abstracts and full texts, 21 reports were identified for evidence synthesis. Of these, two reports were excluded and two described the same study, resulting in a final list of 18 studies (19 reports). For quality assessment, the overall RoB for the 18 studies was categorized as 33.3% low risk, 55.6% with some concerns, and 11.1% high risk. Across the five domains of bias, 70% of the reports were classified as low risk. This systematic review found that the differences in interventions, outcome measures, and design between the studies were associated with a substantial degree of heterogeneity (I2 = 60.74%), with a small overall improvement in outcomes of the interventions relative to their specific control (standard mean difference 0.28; 95% CI, 0.12 to 0.45). There were varying degrees of heterogeneity for individual body regions. This was due, in part, to a small number of studies per bodily location and differences in the study designs. For the neck/shoulder, heterogeneity was moderate, with the clearest positive effect being for physical performance outcomes via other medical devices. For the back, there was substantial heterogeneity between studies, with modest evidence that pain was favorably improved by other medical devices and exercise interventions. For the leg, one study showed a clear large effect for other medical devices (shockwave treatment) on pain with substantial heterogeneity. The best evidence for positive effects was for the knee, with mainly negligible heterogeneity and some benefits from bracing, electrotherapy, and exercise. CONCLUSION: Evidence showed small beneficial effects in pain, strength, and physical performance by individual body regions for some interventions, compared to controls. The best evidence for a positive effect was for the knee. The findings suggest that some benefit may be obtained by including several treatments during deployment in austere environments and prolonged casualty care scenarios of military personnel with MSK injuries. Further research is warranted to better assess the potential benefits of using these treatments during deployments in austere environments as part of an individualized, multimodal approach for MSK injuries.

Recovery of two elite footballers from adductor strain with dry needling and eccentric strengthening: Two case studies.

INTRODUCTION: Groin injuries are common in sports, almost 68% adductor strain among them, which generally more prone in football, soccer, hockey, and other games. The available literature well describes the rehabilitation phase of adductor strain but an application of dry needling on adductor injuries are not yet established. CASE DESCRIPTION: Two national-level younger football players were clinically diagnosed with the adductor strain. They had severe pain on medial aspect of the thigh, aggravated with kicking and functional activity (VAS- 8/10, LEFS 58/80, 69/80). The therapist assessed the patients and designed their rehabilitation protocol as per their findings of the examination. OUTCOME: The lower extremity functional scale (LEFS), global rating scale, and VAS were used as outcome variables. The total intervention was given for 10-12 weeks, follow up had been taken for 4 months. DISCUSSION: The application of dry needling reduced the pain, improved and relieved the symptoms. The eccentric strengthening of the adductors and core stability improved the strength as well as functional activity of the lower limb. The case study is not generalized the effect of treatment. Thus, a randomized control trial is suggested for further study.

Effect of Massage Therapy with Lime (Citrus Aurantifolia) Essential Oil on the Recovery of Delayed Onset of Muscle Soreness in Athletes.

Background: Physical exercise is a systematic exercise to increase muscle strength achieve goals such as improving the athlete's physical and preventing injury. Athletes must do is massage therapy to prevent muscle fatigue and pain due to physical exercise or during competition. The increase of lactic acid levels affects the maximum working ability of muscle fibers, decreases physical performance, and is fatigue in which the onset of pain. Lime essential oil as a topical oil contains high ester substances that have pharmacological effects such as natural analgesic effects to relieve pain. Objective: The purpose of this study was to determine the effect of massage therapy with lime essential oil as a topical oil on the recovery of delayed-onset muscle soreness (DOMS) in athletes. Methods: The participants are boxing athletes, 30 men, 20-22 years old, and non-smokers. Participants were divided into three groups. The exercise group (E) was doing exercises and was not given massage therapy; the exercise massage (EM) group, namely, doing exercises and being massaged with ordinary lotion as a topical oil; and the EM lime (EMC) group did exercises and was given a massage with lime essential oil as the topical oil. Results: The results showed that there was a significant difference in the average levels of lactic acid (p = 0.000) and the athlete's pain intensity (p = 0.000) in the three groups, namely, the exercise group (E), the exercise and massage group (EM), and the exercise and massage with lime essential oil (EMC). Conclusion: This study finds that lime essential oil used as topical massage therapy oil is better for accelerating the DOMS.

Protective effects of dietary curcumin and astaxanthin against heat-induced ROS production and skeletal muscle injury in male and female C57BL/6J mice.

AIMS: This study aimed to: 1) investigate sex differences in heat-induced mitochondrial dysfunction, ROS production, and skeletal muscle injury in mice; 2) evaluate whether curcumin and astaxanthin, alone or together, would prevent those heat-induced changes. MAIN METHODS: Male and female C57BL/6J mice were treated with curcumin and astaxanthin for 10 days, then exposed to 39.5 °C heat for up to 3 h. Heat-induced hyperthermia, changes in mitochondrial morphology and function, and oxidative damage to skeletal muscle were evaluated. KEY FINDINGS: Although female mice had a slightly higher basal core body temperature (Tc) than male mice, peak Tc during heat exposure was significantly lower in females than in males. Heat increased ROS levels in skeletal muscle in both sexes; interestingly, the increases in ROS were greater in females than in males. Despite the above-mentioned differences, heat induced similar levels of mitochondrial fragmentation and membrane potential depolarization, caspase 3/7 activation, and injury in male and female skeletal muscle. Individual treatment of curcumin or astaxanthin did not affect basal and peak Tc but prevented heat-induced mitochondrial dysfunction, ROS increases, and apoptosis in a dose-dependent manner. Moreover, a low-dose combination of curcumin and astaxanthin, which individually showed no effect, reduced the heat-induced oxidative damage to skeletal muscle. SIGNIFICANCE: Both male and female mice can develop mitochondrial dysfunction and oxidative stress in skeletal muscle when exposed to heat stress. High doses of either curcumin or astaxanthin limit heat-induced skeletal muscle injury, but a low-dose combination of these ingredients may increase their efficacy.

Protective Effects of Glutamine and Leucine Supplementation on Sepsis-Induced Skeletal Muscle Injuries.

This study investigated the effects of l-glutamine (Gln) and/or l-leucine (Leu) administration on sepsis-induced skeletal muscle injuries. C57BL/6J mice were subjected to cecal ligation and puncture to induce polymicrobial sepsis and then given an intraperitoneal injection of Gln, Leu, or Gln plus Leu beginning at 1 h after the operation with re-injections every 24 h. All mice were sacrificed on either day 1 or day 4 after the operation. Blood and muscles were collected for analysis of inflammation and oxidative damage-related biomolecules. Results indicated that both Gln and Leu supplementation alleviated sepsis-induced skeletal muscle damage by reducing monocyte infiltration, calpain activity, and mRNA expression levels of inflammatory cytokines and hypoxia-inducible factor-1α. Furthermore, septic mice treated with Gln had higher percentages of blood anti-inflammatory monocytes and muscle M2 macrophages, whereas Leu treatment enhanced the muscle expressions of mitochondrion-related genes. However, there were no synergistic effects when Gln and Leu were simultaneously administered. These findings suggest that both Gln and Leu had prominent abilities to attenuate inflammation and degradation of skeletal muscles in the early and/or late phases of sepsis. Moreover, Gln promoted the switch of leukocytes toward an anti-inflammatory phenotype, while Leu treatment maintained muscle bioenergetic function.

Protective and Recovery Effects of Resveratrol Supplementation on Exercise Performance and Muscle Damage following Acute Plyometric Exercise.

Plyometric exercise (PE) is an effective training method to increase muscle mass and strength. However, excessive or inappropriate conditions might cause exercise-induced muscle damage (EIMD). Resveratrol (RES) is a natural polyphenol plant antitoxin, which improves exercise performance, and exhibits anti-oxidation, anti-inflammatory, and anti-cancer effects. Therefore, this study investigated the effect of RES supplementation on the recovery of muscle damage, inflammation, soreness, muscle power, and anaerobic performance following plyometric-exercise-induced muscle damage (PEIMD). The present study was a double-blind, placebo-controlled research trial. Thirty-six young, untrained males were enrolled into the placebo (n = 12), RES-500 (500 mg RES/day, n = 12), or RES-1000 (1000 mg RES/day, n = 12) group by a jumping height-counterbalanced grouping design. At baseline, to pre-PEIMD, supplements were pre-loaded 7 days before they conducted PEIMD, and the exercise performance, delayed-onset muscle soreness (DOMS) and muscle damage biomarkers were measured over the experimental period at baseline, pre-PEIMD, and post-PEIMD at 2, 24, 48, and 72 h. As a result, we found that, at 72 h post-EIMD, the force peak (FP) and rate of force development (RFD) of the counter movement jump (CMJ) in RES groups showed no significant difference compared to that at baseline but was significantly greater than the placebo group. In the Wingate anaerobic test (WAnT), supplementation in the RES group had a better recovery effect on the relative peak power (RPP), relative mean power (RMP) and fatigue index (FI) (p < 0.05), especially in the high-dose group. For the detection of muscle pain after PEIMD, the RES supplement group was significantly better than the placebo group (p < 0.05). In addition, for muscle damage indexes, such as creatine kinase (CK) and lactate dehydrogenase (LDH), after PEIMD, supplementation with RES could significantly reduce and accelerate recovery (p < 0.05). In addition, the blood biochemical indicators of blood count, liver function, and kidney function showed that RES will not cause adverse risks to the human body. Our results suggest that replenishing RES in advance could effectively reduce muscle pain, increase exercise performance, and decrease muscle damage indicators caused by PEIMD, and the recovery was faster. Therefore, plyometric exercises combined with suitable RES supplementation could be an effective candidate for controlling muscle damage, improving physical adaption, and recovering anaerobic capacity.

A carbonized wormwood modified photothermal microneedle patch for the repair of damaged skeletal muscles.

In this study, we aimed to achieve an efficient repair of damaged skeletal muscles using polyvinyl alcohol (PVA) soluble microneedle patches (MNP) loaded with carbonized wormwood and prostaglandin E2 (inflammatory factors). The introduction of carbonized wormwood imparted the MNP with near-infrared light heating characteristics that improved the efficiency of prostaglandin E2 delivery while also promoting circulation in the damaged muscle area. Our experimental results showed that, compared with the classical moxibustion treatment, the system could more quickly restore muscle strength and the cross-sectional area of muscle bundle fibers in a mouse model of muscular injury. In addition, it could also successfully induce the proliferation and differentiation of muscle stem cells to effectively repair injured muscle tissues. Above all, this light-controlled photothermal MN (microneedle) drug-delivery system avoided the common problems of traditional moxibustion such as large levels of smoke, slow efficacy and risk of scalding. Collectively, we put forward a safe, accurate and efficient approach for skeletal muscle damage treatment using carbonized wormwood.

Multiple and early hyperbaric oxygen treatments enhance muscle healing after muscle contusion injury: a pilot study.

BACKGROUND: The optimal timing of hyperbaric oxygen (HBO2) treatments for the best recovery following muscle injury has yet to be determined. Thus, the optimal number and timing of HBO2 treatments for maximal muscle regeneration were explored. METHODS: The HBO2 treatment protocol consisted of 2.5 ATA 100% oxygen for 120 minutes. Muscle-injured rats were randomized to one of 10 groups: single HBO2 treatment immediately after injury (HBO 1T day 0), one day (HBO 1T day 1), three days (HBO 1T day 3) and five days (HBO 1T day 5) after injury; three HBO2 treatments from immediately after injury to two days after injury (HBO 3T day 0-2), from one to three days after injury (HBO 3T day 1-3), from three to five days after injury (HBO 3T day 3-5), from five to seven days after injury (HBO 3T day 5-7); five daily HBO2 treatments (HBO 5T); and no treatment (NT). RESULTS: HBO 5T and HBO 3T day 0-2, days 1-3 and days 3-5 significantly promoted CD206-positive cell infiltration, satellite cell differentiation and muscle regeneration compared to the NT group. CONCLUSION: Five HBO2 treatments and three HBO2 treatments within three days of injury promote muscle regeneration.

Broad Spectrum Polyphenol Supplementation from Tart Cherry Extract on Markers of Recovery from Intense Resistance Exercise.

BACKGROUND: Tart cherry supplementation has been shown to enhance recovery from strenuous exercise due to its antioxidant properties. The majority of these studies used tart cherry juice, with a significant calorie content. The primary purpose of this study was to assess whether powdered tart cherry extract with minimal calorie content reduces oxidative stress and enhances recovery following intense resistance exercise. METHODS: Thirteen men (mean age: 26.2 ± 5.3 years; height: 184.3 ± 8.2 cm; weight: 92.9 ± 15.6 kg) performed a demanding resistance exercise protocol consisting of 6 sets of 10 repetitions of barbell back squat with 80% 1RM. The protocol was performed once following 7 days of 500 mg of tart cherry extract and once following placebo. Serum protein carbonyl (PC) content, creatine kinase activity (CK) and creatine kinase myocardial band content (CK-MB) were used to assess oxidative stress, skeletal and cardiac muscle damage respectively. Muscle soreness was assessed by visual analog scale. Physical performance was measured by countermovement jump power and handgrip dynamometer strength. RESULTS: There was a significant increase in PC in the placebo (PL) condition when compared to the Tart Cherry (TC) condition at Immediate Post (IP) (PL: 0.4 ± 0.3 vs. TC: - 0.4 ± 0.2 nmol∙mg- 1; p < 0.001), 1 h (PL: 0.3 ± 0.3 vs. TC: - 0.7 ± 0.3 nmol∙mg- 1; p < 0.001) and 24 h (PL: 0.1 ± 0.4 vs. TC: - 0.3 ± 0.5 nmol∙mg- 1; p = 0.010). There was a significant increase in CK activity in PL when compared to the TC at IP (PL: 491.1 ± 280 vs. TC: 296.3 ± 178 U∙L- 1; p = 0.008) and 3 h (PL: - 87 ± 123 vs. TC: 43.1 ± 105.3 U∙L- 1; p = 0.006). There was a significant (p = 0.003) increase in CKMB concentration in PL when compared to the TC (PL: 21.6 ± 12.4 vs. TC: - 0.3 ± 11.8 ng∙ml- 1; p = 0.006) at 1 h post. There was a significant increase in handgrip strength in TC when compared to PL (PL: - 2 ± 5.1 vs. TC: 1.7 ± 3 kg; p = 0.017) at 24 h post. CONCLUSIONS: This study demonstrated that tart cherry extract reduced oxidative stress and markers of muscle and cardiac damage following intense resistance exercise. This occurred along with a prevention of the decrease in handgrip strength seen following the intense exercise protocol, indicating a potential reduction in central fatigue. These benefits were seen with minimal energy intake.

Gyejibokryeong-Hwan improves recovery of injured muscles in mouse model of muscle contusion.

OBJECTIVE: To investigate the effects of Gyejibokryeong-Hwan (Guizhifuling-wan, GBH) on muscle injury in a mouse model of muscle contusion. METHODS: C57/BL6 mouse biceps femoris muscles were injured using the drop-mass method and injured animals were treated orally with GBH (50, 100, or 500 mg/kg) once a day for 7 d. Open field and treadmill running tests were performed to assess functional recovery from muscle injury. The production of pro-inflammatory cytokines was examined by enzyme-linked immunosorbent assay and Western blotting analysis. Expression of the muscle regeneration biomarkers, myoblast determination (MyoD), myogenic factor 5 (Myf5), and smooth muscle actin (α-SMA), in the biceps femoris muscle was investigated at the protein and mRNA level by Western blotting and real time-PCR, respectively. Histological analysis was performed using hematoxylin and eosin staining. Finally, myosin heavy chain production was investigated in differentiated C2C12 myoblasts in the presence of GBH. RESULTS: GBH treatment markedly improved locomotion and running behavior. GBH significantly inhibited the secretion of monocyte chemoattractant protein-1 into the bloodstream in muscle-contused animals. The levels of MyoD, Myf5, and α-SMA protein and mRNA were significantly up-regulated by GBH in injured muscle tissue. Histological studies suggested that GBH facilitated recovery from muscle damage. However, GBH did not induce the production of myosin heavy chain in vitro. CONCLUSION: Overall, the present study suggested that GBH improves the recovery of the injured muscles in the mouse model of muscle contusion.

Efficacy and mechanism of traditional chinese medicine gel in sports-related soft tissue injury / Eficácia e mecanismo do tradicional gel da medicina chinesa em lesões desportivas de tecidos moles / Eficacia y mecanismo del gel de medicina tradicional china en lesiones deportivas de tejidos blandos

ABSTRACT Soft tissue injury is the most common disease in orthopedics, and it is also the most easily neglected disease in sports. Without timely and effective treatment, it is easy to develop into malignant strain and seriously affect life and sports. In view of this, the aim of this study is to analyze the effect and mechanism of traditional Chinese medicine gel in treating such injuries in the light of the characteristics of sports-related soft tissue injury. The right gastrocnemius muscle injury was simulated in 36 adult male rats. Chinese medicine gel and tincture were used to treat it. The contents of interleukin, alanine aminotransferase, blood urea nitrogen and prostaglandin E2 in the blood of rats under different courses of treatment were analyzed to explore recovery in four rats. The results showed that the levels of interleukin and prostaglandin E2 in the blood of rats treated with drugs were significantly lower than those in the control group (p<0.05), indicating that both drugs have obvious therapeutic effects on soft tissue injury. The content of interleukin in the blood of the Chinese medicine gel group was slightly lower than that of the tincture group, indicating that the Chinese medicine gel could affect the recovery of soft tissue injury by affecting leukocyte interleukin. This result is helpful in the treatment of soft tissue injury in sports and to further improve the therapeutic effect of traditional Chinese medicine gel.

RESUMO A lesão dos tecidos moles é a doença mais comum na ortopedia, e é também a doença mais facilmente negligenciada nos esportes. Sem tratamento ágil e eficaz, facilmente evolui para luxações malignas, afetando seriamente a vida e a prática de esportes. Em vista disso, o objetivo deste estudo é analisar o efeito e o mecanismo do gel da medicina tradicional chinesa no tratamento de tais lesões, com base nas características da lesão dos tecidos moles relacionada à prática esportiva. Estimulou-se lesão do músculo gastrocnêmio direito em 36 ratos adultos. O gel e a tintura chinesa foram usados para o tratamento. Foram analisados os conteúdos de interleucina, alanina aminotransferase, ureia sanguínea azoto e prostaglandina E2 no sangue dos ratos sob diferentes tratamentos, de modo a explorar a recuperação de quatro ratos. Os resultados mostraram que os níveis de interleucina e prostaglandina E2 no sangue dos ratos tratados com medicamentos eram significativamente inferiores aos do grupo controle (p<0.05), indicando que ambos os fármacos têm efeitos terapêuticos óbvios sobre lesões dos tecidos moles. O teor de interleucina no sangue do grupo gel chinês medicinal mostrou-se ligeiramente inferior ao do grupo tintura, indicando que o gel medicinal chinês pode afetar a recuperação da lesão nos tecidos moles, afetando o leucócito interleucina. Este resultado é útil para o tratamento de lesões dos tecidos moles relacionadas à prática esportiva e para melhorar ainda mais o efeito terapêutico do gel da medicina chinesa tradicional.

RESUMEN La lesión de los tejidos blandos es la enfermedad más común en la ortopedia, y es también la enfermedad más fácilmente descuidada en los deportes. Sin tratamiento ágil y eficaz, fácilmente evolucionan a luxaciones malignas, afectando seriamente la vida y la práctica de deportes. En vista de eso, el objetivo de este estudio es analizar el efecto y el mecanismo del gel de la medicina tradicional china en el tratamiento de tales lesiones, con base en las características de la lesión de los tejidos blandos relacionada a la práctica deportiva. Se estimuló lesión del músculo gastrocnemio derecho en 36 ratones adultos. El gel y la tintura china fueron usados para el tratamiento. Fueron analizados los contenidos de interleucina, alanina aminotransferasa, urea sanguínea, nitrógeno y prostaglandina E2 en la sangre de los ratones bajo diferentes tratamientos, de modo de explorar la recuperación de cuatro ratones. Los resultados mostraron que los niveles de interleucina y prostaglandina E2 en la sangre de los ratones tratados con medicamentos eran significativamente inferiores a los del grupo control (p<0.05), indicando que ambos fármacos tienen efectos terapéuticos obvios sobre lesiones de los tejidos blandos. El tenor de interleucina en la sangre del grupo gel chino medicinal se mostró ligeramente inferior al del grupo tintura, indicando que el gel medicinal chino puede afectar la recuperación de la lesión en los tejidos blandos, afectando el leucocito interleucina. Este resultado es útil para el tratamiento de lesiones de los tejidos blandos relacionadas a la práctica deportiva y para mejorar aún más el efecto terapéutico del gel de la medicina china tradicional.

Urinary Titin N-Fragment Evaluation in a Randomized Controlled Trial of Beta-Hydroxy-Beta-Methylbutyrate for Acute Mild Trauma in Older Adults.

The effects of beta-hydroxy-beta-methylbutyrate (HMB) complex administration and the significance of titin, a biomarker of muscle injury, in elderly minor trauma patients in acute phase has not been established. In this single-center, randomized controlled study, trauma patients aged ≥ 70 years with an injury severity score < 16 were included. Titin values on days 1 and 3 were measured and the intervention group received HMB complex (2.4 g of HMB + 14 g of glutamine + 14 g of arginine) and the control group received glutamine complex (7.2 g of protein including 6 g of glutamine). The cross-sectional area of the rectus femoris (RFCSA) on ultrasound, grip strength, and the Barthel Index were assessed on the first day of rehabilitation and after 2 weeks. We analyzed 24 HMB and 25 control participants. Titin values on day 3 correlated with grip strength (r = -0.34, p = 0.03) and the Barthel Index (r = -0.39, p = 0.01) at follow-up. HMB complex supplementation had no effect on the RFCSA (2.41 vs. 2.45 cm2, p = 0.887), grip strength (13.3 vs. 13.1 kg, p = 0.946), or the Barthel Index (20.0 vs. 50.0, p = 0.404) at follow-up. Titin values might associate with subsequent physical function. Short-term HMB complex supplementation from acute phase did not ameliorate muscle injury.

Effect of whey vs. soy protein supplementation on recovery kinetics following speed endurance training in competitive male soccer players: a randomized controlled trial.

BACKGROUND: Soccer-specific speed-endurance training induces short-term neuromuscular fatigue and performance deterioration over a 72-h recovery period, associated with elevated markers of exercise-induced muscle damage. We compared the effects of whey vs. soy protein supplementation on field activity, performance, muscle damage and redox responses following speed-endurance training in soccer players. METHODS: Ten well-trained, male soccer players completed three speed-endurance training trials, receiving whey protein (WP), soy protein (SP) or an isoenergetic placebo (PL; maltodextrin) according to a randomized, double-blind, crossover, repeated-measures design. A pre-loading period was applied in each trial during which protein supplementation was individually adjusted to reach a total protein intake of 1.5 g/kg/day, whereas in PL protein intake was adjusted at 0.8-1 g/kg/day. Following pre-loading, two speed-endurance training sessions (1 and 2) were performed 1 day apart, over a 3-day experimental period. During each session, field activity and heart rate were continuously monitored using global positioning system and heart rate monitors, respectively. Performance (isokinetic strength of knee extensors and flexors, maximal voluntary isometric contraction, speed, repeated sprint ability, countermovement jump), muscle damage (delayed-onset of muscle soreness, creatine kinase activity) and redox status (glutathione, total antioxidant capacity, protein carbonyls) were evaluated at baseline (pre), following pre-loading (post-load), and during recovery from speed-endurance training. RESULTS: High-intensity and high-speed running decreased (P ≤ 0.05) during speed-endurance training in all trials, but WP and SP mitigated this response. Isokinetic strength, maximal voluntary isometric contraction, 30-m speed, repeated sprint ability and countermovement jump performance were similarly deteriorated during recovery following speed-endurance training in all trials (P ≤ 0.05). 10 m speed was impaired at 24 h only in PL. Delayed-onset of muscle soreness, creatine kinase, total antioxidant capacity and protein carbonyls increased and glutathione decreased equally among trials following speed-endurance training (P ≤ 0.05), with SP inducing a faster recovery of protein carbonyls only at 48 h (P ≤ 0.05) compared to WP and PL. CONCLUSIONS: In conclusion, increasing daily protein intake to 1.5 g/kg through ingestion of either whey or soy protein supplements mitigates field performance deterioration during successive speed-endurance training sessions without affecting exercise-induced muscle damage and redox status markers. TRIAL REGISTRATION: Name of the registry: clinicaltrials.gov. TRIAL REGISTRATION: NCT03753321 . Date of registration: 12/10/2018.

Polymethoxyflavones in orange peel extract prevent skeletal muscle damage induced by eccentric exercise in rats.

Polymethoxyflavones (PMFs) contained in the peel of citrus fruits have anti-inflammatory, anticancer, and antidepressant effects. However, their effects on skeletal muscle are unknown. We investigated whether PMFs could prevent skeletal muscle damage induced by eccentric exercise in rats. Downhill running for 90 min increased the levels of the inflammatory cytokines, monocyte chemotactic protein-1 (MCP-1), and interleukin-1ß (IL-1ß) in skeletal muscles, especially in vastus lateralis, and the plasma creatine kinase levels. These increases were attenuated by a single oral administration of orange peel extract (OPE) 30 min before downhill running. A mixture of nobiletin, sinensetin, 3,5,6,7,8,3',4'-heptamethoxyflavone, and tangeretin, which are the major PMFs of OPE, also showed similar effects on muscle damage. These results suggest that OPE has a protective effect against eccentric exercise-induced skeletal muscle damage, and that the effects may be attributed to the 4 major PMFs.

The effect of Omega-3 polyunsaturated fatty acid supplementation on exercise-induced muscle damage.

BACKGROUND: Exercise-induced muscle damage (EIMD) results in transient muscle inflammation, strength loss, muscle soreness and may cause subsequent exercise avoidance. Omega-3 (n-3) supplementation may minimise EIMD via its anti-inflammatory properties, however, its efficacy remains unclear. METHODS: Healthy males (n = 14, 25.07 ± 4.05 years) were randomised to 3 g/day n-3 supplementation (N-3, n = 7) or placebo (PLA, n = 7). Following 4 weeks supplementation, a downhill running protocol (60 min, 65% V̇O2max, - 10% gradient) was performed. Creatine kinase (CK), interleukin (IL)-6 and tumour necrosis factor (TNF)-α, perceived muscle soreness, maximal voluntary isometric contraction (MVIC) and peak power were quantified pre, post, and 24, 48 and 72 h post-EIMD. RESULTS: Muscle soreness was significantly lower in N-3 vs PLA group at 24 h post-EIMD (p = 0.034). IL-6 was increased in PLA (p = 0.009) but not in N-3 (p = 0.434) following EIMD, however, no significant differences were noted between groups. Peak power was significantly suppressed in PLA relative to pre-EIMD but not in N-3 group at 24 h post-EIMD. However, no significant difference in peak power output was observed between groups. MVIC, CK and TNF-α were altered by EIMD but did not differ between groups. CONCLUSION: N-3 supplementation for 4 weeks may successfully attenuate minor aspects of EIMD. Whilst not improving performance, these findings may have relevance to soreness-associated exercise avoidance.

Effects of photobiomodulation and swimming on gene expression in rats with the tibialis anterior muscle injury.

The aim of the present study was to evaluate the effects of photobiomodulation (low-level laser therapy (LLLT)) and aquatic exercise on the expression of genes related to muscle regeneration in rats. Wistar rats were divided into five groups: control group (n = 15), non-treated injury group (n = 15), injury+LLLT group (n = 15), injury+aquatic exercise group (n = 15), and injury+LLLT+aquatic exercise group (n = 15). Cryoinjury was performed on the belly of the tibialis anterior (TA) muscle. LLLT was performed daily with an AlGaAs laser (830 nm; beam spot of 0.0324 cm2, output power of 100 mW, energy density of 180 J/cm2, and 58-s exposure time). Animals were euthanized at 7, 14, and 21 days. The TA muscles were removed for gene expression analysis of TGF-ß, Myogenin, and MyoD. The results were statistically analyzed at a significance level of 5%. The cryoinjury increased the expression of genes related to muscle regeneration-MyoD, Myogenin, and TGF-ß-compared to the control group (p < 0.05); the photobiomodulation increased the expression of these genes at day 7 (p < 0.05), decreasing until day 21; and the aquatic exercise increases the expression of the three genes over time. When the two treatments were combined, the expression of the analyzed genes also increased over time. In summary, the results of our study suggest that photobiomodulation (LLLT), when applied alone in cryoinjury, is able to increase the gene expression of MyoD, Myogenin, and TGF-ß at the acute phase, while when combined with aquatic exercises, there is an increase in expression of these genes specially at the long-term treatment.

Whey protein supplementation does not accelerate recovery from a single bout of eccentric exercise.

The current double blind, randomized, placebo-controlled trial with two parallel groups aimed to assess the impact of whey protein supplementation on recovery of muscle function and muscle soreness following eccentric exercise. During a 9-day period, forty recreationally active males received twice daily supplementation with either whey protein (PRO; 60 g/day) or an iso-energetic amount of carbohydrate (CON). Muscle function and soreness were assessed before, and 0, 3, 24, 48, and 72 h after performing 100 drop jumps. Recovery of isometric maximal voluntary contraction (MVC) did not significantly differ between groups (timextreatment, P = 0.56). In contrast, the recovery of isokinetic MVC at 90°·s-1 was faster in CON as opposed to PRO (timextreatment interaction, P = 0.044). Recovery of isokinetic MVC at 180°·s-1 was also faster in CON as opposed to PRO (timextreatment interaction, P = 0.011). Recovery of countermovement jump performance did not differ between groups (timextreatment interaction, P = 0.52). Muscle soreness, CK and CRP showed a transient increase over time (P < 0.001), with no differences between groups. In conclusion, whey protein supplementation does not accelerate recovery of muscle function or attenuate muscle soreness and inflammation during 3 days of recovery from a single bout of eccentric exercise.

L-arginine Improves Plasma Lipid Profile and Muscle Inflammatory Response in Trained Rats After High-Intense Exercise.

Purpose: This study aimed to evaluate whether supplementation with L-arginine alone or in combination with physical exercise training can modulate rats' lipid and inflammatory profiles after a single intense exercise session. Methods: Male Wistar rats were divided into four different groups: control (C), trained (T), supplemented with L-arginine (C + A) and trained and supplemented (T + A). Animals from supplemented groups (C + A and T + A groups) received 300 mg/kg animal body weight L-arginine diluted in 30 mL of drinking water for 8 weeks. Exercise training protocol (moderate intensity-70% achieved in the maximum effort test) was held 5 days/week for 8 weeks. Results: Exercise training induced a decrease in the amount of plasma, cholesterol and triglyceride totals, and skeletal muscle VEGF and CINC. Supplementation alone showed a benefit by reducing LDL levels. Conclusion: Training combined with supplementation showed a pronounced reduction in skeletal muscle VEGF and CINC amount. L-arginine supplementation, especially when associated with the regular aerobic physical exercise at moderate intensity was able to improve not only plasma lipid profile but also the inflammatory response of skeletal muscle immediately after an exhaustive physical exercise session.

Fruit supplementation reduces indices of exercise-induced muscle damage: a systematic review and meta-analysis.

This systematic review and meta-analysis examined the effects of fruit supplements on indices of muscle damage and physical performance measures following muscle-damaging exercise protocols. The PEDro scale and Cochrane's risk of bias tool was used to critically appraise each study, whilst forest plots were generated to report on standardised mean differences (SMD) and p-values. The studies employed a crossover-randomised design, or a randomised controlled placebo design, with measures compared between the supplement (SUPP) and placebo (PLA) conditions at 24 and 48 h following the muscle-damaging exercise protocols. Compared to the PLA condition, the SUPP condition exhibited significantly lower levels of indirect muscle damage markers (p = 0.02; I2 = 44%), inflammatory markers (p = 0.03; I2 = 45%) and oxidative stress (p < 0.001; I2 = 58%), whilst antioxidant capacity was significantly increased (p = 0.04; I2 = 82%) at 24 h post-exercise. The maximal isometric voluntary contraction was significantly greater for the SUPP condition than the PLA at 24 h (p < 0.001; I2 = 81%) and 48 h (p < 0.001; 84%) post-exercise. Only a few studies reported on functional outcome measures (i.e. countermovement jump, cycling, sprint and running maximal oxygen uptake), and the findings appeared conflicting according to qualitative analyses. Fruit supplementation minimised the level of several biomarkers of muscle damage, inflammation and oxidative stress, whilst improved muscular contractility during periods of EIMD. These findings demonstrate that fruit supplements could be used as recovery strategies from strenuous exercise sessions.

Prevalence of Vitamin D Insufficiency and Deficiency in Young, Female Patients With Lower Extremity Musculoskeletal Complaints.

BACKGROUND: Low levels of vitamin D have well-known impacts on bone health, but vitamin D also has a more global role throughout many tissues, including skeletal muscle. The high prevalence of hypovitaminosis D and the vast physiological features of vitamin D have led researchers to examine the influence of vitamin D on physical performance and injury. Because of the critical role of vitamin D in maintaining musculoskeletal health and function, a high rate of hypovitaminosis D among female patients with a variety of musculoskeletal issues could be of high clinical relevance. HYPOTHESIS: There is a high prevalence of low vitamin D in female patients with both acute and overuse sports-related issues of both soft tissue and bone. STUDY DESIGN: Prospective cohort study. LEVEL OF EVIDENCE: Level 3. METHODS: Female patients, aged 16 to 40 years, presenting with lower extremity injury diagnosed within the past 4 weeks, no use of multivitamin or vitamin D supplement, and no history of malabsorption syndrome met the inclusion criteria. Vitamin D levels were assessed and categorized as normal (≥32 ng/mL) and low, which includes insufficient (20.01-31.9 ng/mL) and deficient (≤20 ng/mL). RESULTS: Of the 105 patients enrolled, 65.7% had low vitamin D. Within the low vitamin D cohort, 40.6% were deficient and 59.4% were insufficient. Injuries were grouped into overuse or acute with 74 overuse injuries and 31 acute injuries, exhibiting low vitamin D prevalence of 60.8% and 77.4%, respectively. Patients with ligamentous/cartilaginous injuries exhibited the highest percentage of low vitamin D (76.5%), followed by those with patellofemoral-related complaints (71.0%), muscle/tendon injuries (54.6%), and bone stress injuries (45.5%). In univariable analysis, older age, non-White race, less physical activity, less high-intensity interval training days, less endurance training days, and more rest days showed an association with low vitamin D, but none showed an independent association in multivariable analysis. CONCLUSION: The prevalence of low vitamin D in female patients with various musculoskeletal complaints was high. Clinicians should evaluate for low vitamin D in both acute and overuse injuries. CLINICAL RELEVANCE: In addition to screening, this study suggests that clinicians should evaluate for low vitamin D levels beyond bone stress injuries in the setting of acute and overuse injuries.