Protein ingestion preserves proteasome activity during intense aseptic inflammation and facilitates skeletal muscle recovery in humans.

The ubiquitin-proteasome system (UPS) is the main cellular proteolytic system responsible for the degradation of normal and abnormal (e.g. oxidised) proteins. Under catabolic conditions characterised by chronic inflammation, the UPS is activated resulting in proteolysis, muscle wasting and impaired muscle function. Milk proteins provide sulphur-containing amino acid and have been proposed to affect muscle inflammation. However, the response of the UPS to aseptic inflammation and protein supplementation is largely unknown. The aim of this study was to investigate how milk protein supplementation affects UPS activity and skeletal muscle function under conditions of aseptic injury induced by intense, eccentric exercise. In a double-blind, cross-over, repeated measures design, eleven men received either placebo (PLA) or milk protein concentrate (PRO, 4×20 g on exercise day and 20 g/d for the following 8 days), following an acute bout of eccentric exercise (twenty sets of fifteen eccentric contractions at 30°/s) on an isokinetic dynamometer. In each trial, muscle biopsies were obtained from the vastus lateralis muscle at baseline, as well as at 2 and 8 d post exercise, whereas blood samples were collected before exercise and at 6 h, 1 d, 2 d and 8 d post exercise. Muscle strength and soreness were assessed before exercise, 6 h post exercise and then daily for 8 consecutive days. PRO preserved chymotrypsin-like activity and attenuated the decrease of strength, facilitating its recovery. PRO also prevented the increase of NF-κB phosphorylation and HSP70 expression throughout recovery. We conclude that milk PRO supplementation following exercise-induced muscle trauma preserves proteasome activity and attenuates strength decline during the pro-inflammatory phase.

Repeated Bout Effect of Downhill Running on Physiological Markers of Effort and Post Exercise Perception of Soreness in Trained Female Distance Runners.

This study examined the effect of repeated bouts of level and downhill running on physiological markers of effort and exercise-induced muscle soreness in trained female distance runners. Ten participants (Age: 24.4 ± 2.0 years; V̇O2peak: 52.9 ± 1.1 mL·kg-1·min-1), naïve to downhill running, completed six alternate 5 min trials of level and downhill running (-15%) at a 70% velocity at V̇O2peak on two occasions, three weeks apart. Perceived muscle soreness was measured upon completion and in the 72 h post exercise. V̇O2, Heart Rate (HR), Blood Lactate (BLa), and Respiratory Exchange Ratio (RER) were lower running downhill (p < 0.016, ηp2 > 0.541). For the first downhill run, Rating of Perceived Exertion (RPE) was higher compared to that for level running (p = 0.051; d = 0.447), but for the remaining trials, RPE was lower when running downhill (p < 0.004; d > 0.745). V̇O2, HR, and RER were not different in the second bout (p > 0.070, ηp2 < 0.318); however, V̇O2 was lower in each downhill trial (Δ = 1.6-2.2 mL·kg-1·min-1; d = 0.382-0.426). In the second bout, BLa was lower (p = 0.005, ηp2 = 0.602), RPE in the first trial was lower (p = 0.002; d = 0.923), and post exercise perceived soreness of the gastrocnemius, quadriceps, and hamstrings was attenuated (p < 0.002; ηp2 > 0.693). Perceived soreness of the gluteal muscles was lower in the second bout immediately post exercise, 24 h, and 48 h post exercise (p < 0.025; d > 0.922). A repeated bout of downhill running attenuated perceived muscle soreness and may modulate the physiological and perceived physical demand of a second bout of level and downhill running.

Effects of foam rolling on hamstrings stiffness in damaged and non-damaged muscle states.

Introduction: The aim of this study was to examine the effects of foam rolling (FR) on hamstring muscles stiffness in both non-damaged and exercise-induced muscle damage (EIMD) states, using shear wave ultrasound elastography to measure changes in shear modulus. Methods: Fourteen healthy adults (25.5 ± 4.7 years) participated in a within-participant repeated measures design, with a 2-minute FR intervention applied on one leg and contralateral leg serving as a control. The damaging protocol encompassed maximal eccentric knee extensions performed on an isokinetic dynamometer and the Nordic hamstring exercise, consisting of 3 sets of 10 and 6 repetitions, respectively. Measurement were taken at baseline and then 1 h, 24 h and 48 h after the damaging protocol. Results: The results indicated no significant time × leg interaction for shear modulus in biceps femoris, semimembranosus, and semitendinosus muscles in both non-damaged and damaged states. Notably, there was a significant increase in biceps femoris (p = 0.001; η2 = 0.36) and semitendinosus (p < 0.001; η2 = 0.44) shear modulus after EIMD, but no significant differences were found between the FR and control leg, which was also the case for muscle soreness, range of motion, and passive resistive torque (p = 0.239-0.999 for interactions). Discussion: The absence of significant changes post-FR intervention suggests a limited role of short-duration FR in altering muscle stiffness during recovery from EIMD. These findings contribute to the understanding of FR's role in muscle recovery. Although this was not directly investigated, our results suggest a predominance of central mechanisms rather than direct mechanical modifications in muscle properties. This research highlights the necessity for additional investigations to explore how FR interventions influence muscles in different states and to elucidate the mechanisms underlying these influences.

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.

Fish oil supplementation fails to modulate indices of muscle damage and muscle repair during acute recovery from eccentric exercise in trained young males.

We aimed to investigate the influence of 4-wk of fish oil (FO) supplementation on markers of muscle damage, inflammation, muscle soreness, and muscle function during acute recovery from eccentric exercise in moderately trained males. Sixteen moderately-trained males ingested 5 g/d of FO (n = 8) or soybean oil (placebo) capsules (n = 8) for 4-wk prior to- and 3-d following an acute eccentric exercise bout. Eccentric exercise consisted of 12 sets of isokinetic knee extension and knee flexion. Indices of muscle damage, soreness, function and inflammation were measured at baseline and during exercise recovery. Eccentric exercise elicited an increase in muscle soreness (p < 0.010) and thigh volume (p < 0.001), and reduced peak isometric torque by 31.7 ± 6.9%, (p < 0.05, 95% CI 10.6-52.8) during 3-d of recovery. Blood omega-3 polyunsaturated fatty acid concentration was 14.9 ± 2.4% higher in FO than PLA (p < 0.01, 95% CI 9.8-20.1). However, FO did not ameliorate the cumulative creatine kinase response (expressed as AUC; p = 0.368), inflammation (p = 0.400), muscle soreness (p > 0.140), or muscle function (p > 0.249) following eccentric exercise. FO supplementation confers no clear benefit in terms of ameliorating the degree of muscle damage, or facilitating the muscle repair process, during acute eccentric exercise recovery. These data suggest that FO supplementation does not provide an effective nutritional strategy to promote exercise recovery, at least in moderately-trained young men.Abbreviations: ANOVA: Analysis of variance; AUC: Area under curve; CI: Confidence interval; CK: Creatine kinase; CMJ: Countermovement jump; COX: Cyclooxygenase; CRP: C-reactive protein; DHA: Docosahexaenoic acid; DOMS: Delayed-onset muscle soreness; EIMD: Exercise-induced muscle damage; En%: Energy percent; EPA: Eicosapentaenoic acid; FO: Fish oil; IL-6: Interleukin-6; LDH: Lactate dehydrogenase; LOX: Lipoxygenase; Mb: Myoglobin; mTOR: Mechanistic target of rapamycin; PLA: Placebo; ROM: Range of motion; ROS: Reactive oxygen species; SD: Standard deviation; SEM: Standard error of the mean; TNF-α: Tumour necrosis factor alpha; VAS: Visual analogue scale; Ω3-PUFA: Omega-3 polyunsaturated fatty acids; Ω6-PUFA: Omega-6 polyunsaturated fatty acidsHighlightsThe anti-inflammatory properties of omega-3 polyunsaturated fatty acids, alongside their propensity to incorporate into the muscle phospholipid membrane underpins the idea that fish oil supplementation may attenuate muscle damage and promote muscle repair following eccentric-based exercise.Four weeks of high-dose (5 g/d) fish oil supplementation prior to eccentric exercise failed to attenuate the rise in creatine kinase concentration and muscle soreness during acute exercise recovery in physically-active young men.Future studies are warranted to investigate the efficacy of combining omega-3 polyunsaturated fatty acids with other nutrients (i.e. protein/amino acids) for the promotion of muscle recovery following eccentric-based damaging exercise.

Increased game frequency period crossing Ramadan intermittent fasting decreases fat mass, sleep duration, and recovery in male professional basketball players.

Background: Increased basketball game frequency may affect athlete performances, especially during Ramadan intermittent fasting (RIF). The objective of the present investigation was to assess the impacts of increased game frequency periods crossing the RIF on body composition, sleep habits, indices of well-being, recovery state, and dietary intake in professional male basketball players. Methods: Twenty-eight professional basketball players participated in this study and were divided into increased-games-frequency (INCR) or normal-games-frequency (NORM) groups. INCR trained four times and completed two games per week, whereas NORM completed only one game per week. During the first and fourth weeks of RIF, the following variables were assessed: internal load (weekly session rating of perceived exertion (s-RPE), heartrate (HR)), dietary intake, body composition, sleep quality (PSQI survey), well-being indices questionnaire (sleep, fatigue, stress, delayed onset of muscle soreness (DOMS)), and recovery state with the Total Quality Recovery (TQR) questionnaire. Results: The internal load significantly increased after 4 weeks of RIF in INCR compared to NORM (p < 0.001). Significant decrease of TQR, sleep duration, and a significant increase of DOMS only for INCR (26.93%, p < 0.001, ES = 0.48, small; 33.83%, p < 0.001, ES = 0.40, small; 161.17%, p < 0.001, ES = 0.32, small; respectively). Significant group × time interaction was observed for body mass (p = 0.006, ES = 0.46, small) and body fat percentage (p = 0.025, ES = 0.33, small), with INCR having a greater decrease in all these values. Conclusion: Increased game frequency period crossing RIF decreases fat mass, sleep duration, and recovery in professional basketball players, which may consequently affect performance and health.

The Effect of Protein Supplementation versus Carbohydrate Supplementation on Muscle Damage Markers and Soreness Following a 15-km Road Race: A Double-Blind Randomized Controlled Trial.

We assessed whether a protein supplementation protocol could attenuate running-induced muscle soreness and other muscle damage markers compared to iso-caloric placebo supplementation. A double-blind randomized controlled trial was performed among 323 recreational runners (age 44 ± 11 years, 56% men) participating in a 15-km road race. Participants received milk protein or carbohydrate supplementation, for three consecutive days post-race. Habitual protein intake was assessed using 24 h recalls. Race characteristics were determined and muscle soreness was assessed with the Brief Pain Inventory at baseline and 1-3 days post-race. In a subgroup (n = 149) muscle soreness was measured with a strain gauge algometer and creatine kinase (CK) and lactate dehydrogenase (LDH) concentrations were measured. At baseline, no group-differences were observed for habitual protein intake (protein group: 79.9 ± 26.5 g/d versus placebo group: 82.0 ± 26.8 g/d, p = 0.49) and muscle soreness (protein: 0.45 ± 1.08 versus placebo: 0.44 ± 1.14, p = 0.96). Subjects completed the race with a running speed of 12 ± 2 km/h. With the Intention-to-Treat analysis no between-group differences were observed in reported muscle soreness. With the per-protocol analysis, however, the protein group reported higher muscle soreness 24 h post-race compared to the placebo group (2.96 ± 2.27 versus 2.46 ± 2.38, p = 0.039) and a lower pressure muscle pain threshold in the protein group compared to the placebo group (71.8 ± 30.0 N versus 83.9 ± 27.9 N, p = 0.019). No differences were found in concentrations of CK and LDH post-race between groups. Post-exercise protein supplementation is not more preferable than carbohydrate supplementation to reduce muscle soreness or other damage markers in recreational athletes with mostly a sufficient baseline protein intake running a 15-km road race.

Effect of Large Versus Small Range of Motion in the Various Intensities of Eccentric Exercise-Induced Muscle Pain and Strength.

The purpose was to investigate eccentric (ECC) exercise with full range of motion (FROM) induce a greater magnitude of delayed onset muscle soreness (DOMS), pain, functional limitations compared to partial range of motion (PROM; outer 60° of ROM). Thirty-four participants (men and women) aged between 18 and 30 years performed ECC exercise protocol on elbow and knee muscles (5 × 10 repetitions each session) using their 15%/25%/35% of maximal voluntary isometric contraction (MVIC) with PROM (week 2-4) and FROM (week 6-8). Two days a week, ECC exercises and remaining days the subjective and objective assessments were carried out (activities of daily living (ADL), pain (visual analogue scale (VAS), pain pressure threshold (PPT)), and MVIC. The ECC exercise with FROM showed moderate pain (0-3.5) in ADL (pulling a heavy object and descending stairs), VAS, and PPT for elbow extensors and knee flexors and showed a statistically significant difference (p ≤ 0.05) compared to PROM ECC protocol. The muscle strength was increased in FROM ECC exercise than PROM ECC exercise and ranged between 23.16% and 28.22%. ECC exercise performed with FROM induced a higher degree of DOMS, pain, ADL limitations than PROM. The study outcomes can be used for beginner sedentary older adults as well as young athletes.

The Effect of a Resistance Training Session on Physiological and Thermoregulatory Measures of Sub-maximal Running Performance in the Heat in Heat-Acclimatized Men.

BACKGROUND: The current study examined the acute effects of a lower body resistance training (RT) session on physiological and thermoregulatory measures during a sub-maximal running protocol in the heat in heat-acclimatized men. Ten resistance-untrained men (age 27.4 ± 4.1 years; height 1.78 ± 0.06 m; body mass 76.8 ± 9.9 kg; peak oxygen uptake 48.2 ± 7.0 mL kg-1 min-1) undertook a high-intensity RT session at six-repetition maximum. Indirect muscle damage markers (i.e., creatine kinase [CK], delayed-onset muscle soreness [DOMS], and countermovement jump [CMJ]) were collected prior to, immediately post and 24 and 48 h after the RT session. The sub-maximal running protocol was performed at 70% of the ventilatory threshold, which was conducted prior to and 24 and 48 h following the RT session to obtain physiological and thermoregulatory measures. RESULTS: The RT session exhibited significant increases in DOMS (p < 0.05; effect size [ES]: 1.41-10.53), whilst reduced CMJ (p < 0.05; ES: - 0.79-1.41) for 48 h post-exercise. There were no differences in CK (p > 0.05), although increased with moderate to large ES (0.71-1.12) for 48 h post-exercise. The physiological cost of running was increased for up to 48 h post-exercise (p < 0.05) with moderate to large ES (0.50-0.84), although no differences were shown in thermoregulatory measures (p > 0.05) with small ES (0.33). CONCLUSION: These results demonstrate that a RT session impairs sub-maximal running performance for several days post-exercise, although thermoregulatory measures are unperturbed despite elevated muscle damage indicators in heat-acclimatized, resistance untrained men. Accordingly, whilst a RT session may not increase susceptibility to heat-related injuries in heat-acclimatized men during sub-maximal running in the heat, endurance sessions should be undertaken with caution for at least 48 h post-exercise following the initial RT session in resistance untrained men.

Protection against muscle damage induced by electrical stimulation: efficiency of a preconditioning programme.

PURPOSE: The aim of this study was to explore the efficiency of a preconditioning programme composed of neuromuscular electrical stimulation (NMES) in the protection against muscle damage induced by a subsequent bout of NMES. METHODS: Sixteen male volunteers were split up into a control group (CG; n = 8) and a preconditioned group (PCG; n = 8). Both groups attended two NMES bouts (test 1 and test 2) spaced 5 weeks apart. Each one consisted in 100 quadriceps contractions and 100 hamstrings contractions. PCG attended five additional progressive NMES sessions between test 1 and test 2. The outcome measures were the changes in muscle soreness [0-10 pain score on visual analogue pain scale (VAS)], muscle flexibility and serum creatine kinase (CK) activity; they were assessed before (pre-T1) and after (post-T1) test 1 and before (pre-T2) and after (post-T2) test 2. RESULTS: Damage markers increased similarly in both groups after test 1 (at post-T1, VAS scores = 4·18 ± 2 and 4·43 ± 1·56 cm in CG and PCG, respectively; CK activity = 2307 ± 3774 and 1671 ± 1790 IU l(-1) in CG and PCG, respectively). Compared with test 1, these damage markers were reduced after test 2 in CG (at post-T2, VAS score = 2·68 ± 1·27 cm and CK activity = 218 ± 72 IU l(-1) ). Muscle soreness was further reduced after test 2 in PCG (VAS score = 0·37 ± 0·74 cm). CONCLUSIONS: A protective effect against muscle damage can be obtained after only one NMES bout, and an additional protective effect can be induced by a preconditioning programme.