中医消除运动性肌肉疲劳临床实验研究之一——外用、内服中药对人体骨骼肌两周离心运动肌肉酸痛和形态学影响

30名志愿受试者分别以最大等长收缩力的 6 0 % (第 1周 )和 80 % (第 2周 )完成连续 2周上臂屈肌离心收缩训练 ,随机分成中药内服、外用和对照组进行治疗和处理 ,对肌肉酸痛部位和等级、肘关节屈曲角度、肘关节伸直角度、上臂臂围、上臂屈肌硬度、血清CK以及肱二头肌回声的平均光密度和肌肉厚度超声检测进行观测。结果显示 ,强度增加后的第 2周 ,肌肉酸痛程度、肘关节伸直角度和血清CK值在实验结束时均已恢复正常 ;肘关节屈曲角度、上臂臂围和肌肉硬度等与延迟性肌肉酸痛 (DOMS)后期肌肉增粗有关的指标 ,在第 2周训练强度增加后呈恢复趋势 ,无继续加重现象 ;大强度离心训练后肌肉厚度增加 ,训练后第 3天出现肌肉回声增强的改变。实验表明 ,内服和外用中药对DOMS的消除均有一定的作用 ,尤其是外用药对本实验指标的改善更明显一些     

The effects of vitamin C supplementation on symptoms of delayed onset muscle soreness

AIM: The aim of this study was to compare the effects of 8 days of vitamin C (VC) supplementation on elbow flexor delayed onset muscle soreness (DOMS) to 8 days of placebo ingestion. METHODS: For 3 days prior to an exercise bout (2 x 20 eccentric elbow extensions), and for 5 days after, a treatment group ingested 3 x 1000 mg/day of VC versus 3 x 50 mg/day of glucose ingestion for the placebo group over the same time period. All subjects were prescreened via dietary recall to exclude any subjects with habitual VC consumption greater than 400 mg/day. Subject comprised 24 subjects (male and female) randomly divided into 2 groups of 12 subjects. Treatment group comprised 5 females and placebo group comprised 8 females. RESULTS: Data from a repeated measures ANOVA indicate that DOMS was successfully induced in both groups via significant time effects for strength loss (P = 0.0001), point tenderness (P = 0.0001), elbow flexor decreased range of motion (P = 0.013), and subjective pain (P = 0.0001). However, there were no significant between group differences in response to any of the aforementioned variables: strength loss (P = 0.202), point tenderness (P = 0.824), elbow flexor range of motion (P = 0.208), subjective pain (P = 0.342). CONCLUSIONS: The results of this study suggest that a VC supplementation protocol of 3 x 1000 mg/day for 8 days is ineffective in protecting against selected markers of DOMS.     

Delayed-onset muscle soreness does not reflect the magnitude of eccentric exercise-induced muscle damage

This study investigated the relationship between delayed-onset muscle soreness and other indicators of muscle damage following eccentric exercise. Male students (n = 110) performed 12 (12ECC), 24 (24ECC), or 60 maximal eccentric actions of the elbow flexors (60ECC). Maximal isometric force, relaxed and flexed elbow joint angles, upper arm circumference, and plasma creatine kinase activity were assessed immediately before and after, and for 4 days after exercise. Muscle soreness (SOR) was evaluated by a visual analog scale (a 50-mm line, 0: no pain, 50: extremely painful) when the elbow flexors were palpated (SOR-Pal), flexed (SOR-Flx) and stretched (SOR-Ext). Although 24ECC and 60ECC resulted in significantly (P <; 0.05) larger changes in all indicators and slower recovery compared to 12ECC, no significant differences were evident for SOR-Pal and SOR-Flx between 12ECC and 24ECC, or 12ECC and 60ECC. In contrast, SOR-Ext was significantly (P <; 0.05) lower for 12ECC compared to 24ECC and 60ECC. A Pearson product-moment correlation showed SOR-Pal did not correlate significantly with any indicators, however, SOR-Ext and SOR-Flx showed weak (r <; 0.32) but significant (P <; 0.05) correlations with other indicators. Because of generally poor correlations between DOMS and other indicators, we conclude that use of DOMS is a poor reflector of eccentric exercise-induced muscle damage and inflammation, and changes in indirect markers of muscle damage and inflammation are not necessarily accompanied with DOMS.     

Electro-membrane microcurrent therapy reduces signs and symptoms of muscle damage

PURPOSE: Delayed onset muscle soreness (DOMS) occurs after unaccustomed physical activity or competitive sport, resulting in stiff, painful muscles with impaired function. Acustat electro-membrane microcurrent therapy has been used to treat postoperative pain and soft tissue injury; however, its efficacy in reducing symptoms of muscle damage is not known. METHODS: Thirty healthy men were recruited for a double-blind, placebo-controlled trial. The muscles of their nondominant arms were damaged using an eccentric-exercise protocol. Subjects were then randomly assigned to treatment with either Acustat or a matching placebo membrane for 96 h and monitored for a total of 168 h. RESULTS: Subjects in both groups experienced severe pain and swelling of the elbow flexors after the eccentric exercise. After 24 h, the elbow joint angle of the placebo group had increased significantly more than those in the Acustat group (13.7 +/- 8.9 degrees vs 7.5 +/- 5.5 degrees; placebo vs Acustat, P < 0.05), possibly as a consequence of the elbow flexor muscles shortening. For the first 48 h after exercise, maximum voluntary contraction of the elbow flexor muscles was significantly impaired in the placebo group by up to 25% (P < 0.05), whereas muscle function was unchanged in the Acustat group. Peak plasma creatine kinase activity was also lower in the Acustat group (peak = 777 +/- 1438 U.L-1) versus the placebo group (peak = 1918 +/- 2067 U.L-1; (P < 0.05). The membranes were well tolerated by the subjects in both groups without any adverse effects. CONCLUSION: These data show that treatment of muscle damage with Acustat electro-membrane microcurrent therapy reduces the severity of the symptoms. The mechanisms of action are unknown but are likely related to maintenance of intracellular Ca2+ homeostasis after muscle damaging exercise.     

The effects of preexercise stretching on muscular soreness, tenderness and force loss following heavy eccentric exercise

The present study sought to investigate the effects of preexercise stretching on delayed onset muscle soreness (DOMS), i.e. soreness, tenderness and loss of muscle force, that usually occurs after strenuous or unaccustomed eccentric exercise. Ten female volunteers performed 10 sets of 10 maximal isokinetic eccentric contractions for knee flexion with both legs after a 5-min ergometer cycling warm-up. Prior to the exercise for one leg, randomly chosen, 4 x 20 s of static stretching for the hamstring muscle group was implemented. Rated soreness, tenderness on algometer pressure and loss of maximal eccentric contractile force was evaluated preexercise and 24, 48 and 96 h postexercise. The exercise bout produced severe DOMS, with parameters peaking and troughing at 48 h postexercise. However, no significant differences were found, regarding any of the parameters, when comparing stretched and nonstretched legs. The present study thus suggests that preexercise static stretching has no preventive effect on the muscular soreness, tenderness and force loss that follows heavy eccentric exercise.     

The effects of a repeated bout of eccentric exercise on indices of muscle damage and delayed onset muscle soreness

This study examined markers of muscle damage following a repeated bout of maximal isokinetic eccentric exercise performed prior to full recovery from a previous bout. Twenty non-resistance trained volunteers were randomly assigned to a control (CON, n=10) or experimental (EXP, n=10) group. Both groups performed 36 maximal isokinetic eccentric contractions of the elbow flexors of the non-dominant arm (ECC1). The EXP group repeated the same eccentric exercise bout two days later (ECC2). Total work and peak eccentric torque were recorded during each set of ECC1 and ECC2. Isometric torque, delayed onset muscle soreness (DOMS), flexed elbow angle and plasma creatine kinase (CK) activity were measured prior to and immediately following ECC1 and ECC2. at 24h intervals for 7 days following ECC1 and finally on day 11. In both groups, all dependent variables changed significantly during the 2 days following ECC1. A further acute post-exercise impairment in isometric torque (30 +/- 5%) and flexed elbow angle (20 +/- 4%) was observed following ECC2 (p<0.05), despite EXP subjects producing uniformly lower work and peak eccentric torque values during ECC2 (p<0.05). No other significant differences between the CON and EXP groups were observed throughout the study (p>0.05). These findings suggest that when maximal isokinetic eccentric exercise is repeated two days after experiencing of contraction-induced muscle damage, the recovery time course is not significantly altered.     

Acute adaptation to low volume eccentric exercise.

PURPOSE: Many symptoms of eccentric muscle damage can be substantially reduced if a similar eccentric bout is repeated within several weeks of the initial bout. The purpose of this study was to determine whether a nondamaging, low repetition, low volume eccentric exercise bout could also provide a protective/adaptive effect. METHODS: Subjects were assigned to a control (CON), eccentric exercise (ECC), or low volume familiarized eccentric exercise group (LV+ECC). Before the study, the LV+ECC group performed six maximal eccentric contractions during two familiarization sessions. The main eccentric bout targeted the elbow flexor muscle group and consisted of 36 maximal eccentric contractions. Muscle soreness, upper arm girth, elbow angle, creatine kinase activity, isometric torque, and concentric and eccentric torque at 0.52 and 3.14 rad.s-1 were assessed 0, 1, 2, 3, 4, 7, and 10 d postexercise. RESULTS: No evidence of muscle damage was observed as a result of the low volume eccentric bouts. Nevertheless, with the exception of muscle soreness and concentric torque, all variables recovered more rapidly in the LV+ECC group (P < 0.05). CONCLUSION: Adaptation to eccentric exercise can occur in the absence of significant muscle damage. Exposure to a small number of nondamaging eccentric contractions can significantly improve recovery after a subsequent damaging eccentric bout. Furthermore, this adaptation appears to be mode-specific and not applicable to concentric contractions.     

Changes in markers of muscle damage of middle-aged and young men following eccentric exercise of the elbow flexors

It is well documented that unaccustomed eccentric exercise induces muscle damage, but the responses of middle-aged individuals to a bout of eccentric exercise have not been reported. The purpose of this study was to compare changes in indirect markers of muscle damage following eccentric exercise of the elbow flexors between 12 young (age: 19.4+/-0.4 years, height: 173.5+/-2.0cm, body mass: 65.8+/-3.5kg) and 12 middle-aged men (48.0+/-2.1 years, 169.5+/-1.7cm, 67.3+/-1.6kg). It was hypothesized that middle-aged men would be more susceptible to muscle damage than young men. All subjects performed six sets of five eccentric actions of the elbow flexors using a dumbbell of 40% of maximal isometric strength (MVC). Changes in MVC, elbow joint angles and range of motion, upper arm circumference, plasma creatine kinase activity and myoglobin concentration, and muscle soreness before, immediately after, and 1, 2, 3, and 4 days after exercise were compared between the young and middle-aged groups by a two-way repeated measures ANOVA. All criterion measures changed significantly (P<0.05) after exercise, but no significant differences in the changes in the measures except for muscle soreness were evident between groups. Development of muscle soreness after exercise was significantly (P<0.05) lower (approximately a half of the value) for the middle-aged group compared with the young group. These results did not support the hypothesis that middle-aged men would be more susceptible to muscle damage than young men.     

Differential expression of muscle damage in humans following acute fast and slow velocity eccentric exercise

We sought to determine if the velocity of an acute bout of eccentric contractions influenced the duration and severity of several common indirect markers of muscle damage. Subjects performed 36 maximal fast (FST, n = 8: 3.14 rad x s(-1)) or slow (SLW, n = 7: 0.52 rad x s(-1)) velocity isokinetic eccentric contractions with the elbow flexors of the non-dominant arm. Muscle soreness, limb girth, plasma creatine kinase (CK) activity, isometric torque and concentric and eccentric torque at 0.52 and 3.14 rad x s(-1) were assessed prior to and for several days following the eccentric bout. Peak plasma CK activity was similar in SLW (4030 +/- 1029 U x 1(-1)) and FST (5864 +/- 2664 U x 1(-1)) groups, (p > 0.05). Both groups experienced similar decrement in all strength variables during the 48 hr following the eccentric bout. However, recovery occurred more rapidly in the FST group during eccentric (0.52 and 3.14 rad x s(-1)) and concentric (3.14 rad x s(-1)) post-testing. The severity of muscle soreness was similar in both groups. However, the FST group experienced peak muscle soreness 48 hr later than the SLW group (24 hr vs. 72 hr). The SLW group experienced a greater increase in upper arm girth than the FST group 20 min, 24 hr and 96 hr following the eccentric exercise bout. The contraction velocity of an acute bout of eccentric exercise differentially influences the magnitude and time course of several indirect markers of muscle damage.     

The efficacy of ice massage in the treatment of exercise-induced muscle damage

The purpose of this investigation was to, firstly, examine the effects of repeated applications of ice massage on the indirect markers associated with muscle damage using a within-subjects cross-over design and secondly, to examine how ice massage affects muscle function in both static and dynamic contractions following unaccustomed eccentric exercise. Twelve males performed damaging exercise on two separate occasions. The protocol consisted of three sets of 10 maximal eccentric repetitions of the elbow flexors using isokinetic dynamometry. Subjects were randomly assigned to an ice massage group or placebo group and received treatments immediately post-exercise, 24 and 48 h post-exercise. Muscle function (maximal isometric, slow and fast isokinetic contractions), creatine kinase, myoglobin, muscle soreness, limb girth and range of motion were measured pre, immediately post, 24, 48, 72 and 96 h post-exercise. Significant time effects were observed for all dependent variables (P<0.05). There were no significant differences between treatments. Ice massage is ineffective in reducing the indirect markers associated with exercise-induced muscle damage and enhancing recovery of muscle function in male exercisers unaccustomed to eccentric biased exercise.     

Early alterations in serum creatine kinase and total cholesterol following high intensity eccentric muscle actions

AIM: The purpose of this experiment was to assess the levels of muscle soreness, serum total cholesterol (TC) and creatine kinase (CK) in the first 48 hours following fatiguing eccentric exercise performed with the triceps brachii. METHODS: Eleven untrained male college students performed a total of 50 eccentric elbow extensions in 8 sets (6 x 7 and 2 x 4) with a load equal to 85% of their maximal concentric elbow extension strength. Isometric elbow extension strength, muscle soreness and circumference, and serum CK and TC concentrations were measured before, immediately after, and 2, 24 and 48 hours after the exercise. RESULTS: Statistically reliable changes in isometric strength, serum CK and TC, muscle soreness and upper arm circumference occurred within the first 48 hours following eccentric exercise. Serum TC concentrations exhibited a very rapid (within 2 hours) reduction from pre-exercise values after eccentric exercise to a relatively stable concentration of approximately 85% of baseline. CONCLUSION: These results suggest that serum TC concentration may follow the time-course of reductions in force generating capacity more closely than other biochemical markers of muscle damage.     

Eccentric exercise effect on blood oxidative-stress markers and delayed onset of muscle soreness

PURPOSE: This study examined the effects of a single bout of high-intensity eccentric exercise (EE) on blood protein carbonyls, glutathione status, and muscle damage indicators to ascertain whether blood markers of oxidative stress are elevated at the time delayed onset of muscle soreness (DOMS) occurs. METHODS: Eight healthy men (26.5 +/- 1.5 yr) performed 60 eccentric contractions at approximately 135-150% dominant arm maximum isometric force (MIF) using their nondominant arm elbow flexors. DOMS, range of motion (ROM), MIF, and blood were obtained before, immediately after, and 24, 48, 72, and 96 h after the EE. Blood samples were analyzed for plasma creatine kinase (CK) activity, and protein carbonyls (PC), and erythrocyte glutathione status. RESULTS: A significant decrease in MIF occurred at all times after the EE. ROM decreased from 24 to 96 h, and DOMS increased 24 to 72 h in the nondominant arm as indicated by a repeated measure ANOVA. Plasma CK activity peaked at 72 h (1620 +/- 500 IU x L(-1)) compared with baseline (154 +/- 27 IU x L(-1). Erythrocyte-reduced glutathione (GSH) concentration was not significantly affected by the EE but tended to decrease 23% by 24 h and continued at this level for 96 h. Oxidized glutathione (GSSG) and total glutathione were unchanged over time. A significant increase in plasma PC occurred at 24 and 48 h after eccentric exercise. CONCLUSIONS: The results suggest that 60 EE at 135-150% MIF can result in DOMS, with decreased muscle function and increases in plasma PC at 24 and 48 h without alterations in blood glutathione status.     

Sex differences in response to maximal eccentric exercise

PURPOSE: This study examined sex differences in strength loss, muscle soreness, and serum creatine kinase (CK) and myoglobin (Mb) after high-intensity eccentric exercise of the elbow flexors in a large group of men and women. METHODS: One hundred participants (58 women, 42 men) performed 50 maximal eccentric contractions of the elbow flexor muscles of their nondominant arm. Maximum isometric voluntary contraction (MVC) was recorded at baseline, immediately after exercise, and at 0.5 (12-14 h), 3, 4, 7, and 10 d after exercise. Blood samples for serum CK activity and Mb were taken at baseline and at 4, 7, and 10 d after exercise. Soreness was evaluated at baseline and at 0.5, 3, 4, 7, and 10 d after exercise. RESULTS: Women experienced significantly greater relative strength loss immediately after exercise (-57.8% +/- 19.1) than men (-50.4% +/- 16.9%) (independent t-test; P < or = 0.05), and a greater percentage of women experienced more than 70% strength loss immediately after exercise compared with men (34.4% of women; 7.1% of men). Men exhibited a larger CK response compared with women (ANCOVA; P < or = 0.05), partly because there were more men who were high responders. There were no significant differences between the sexes for serum Mb or soreness measures. Generally, stronger relationships among CK, soreness, and strength-loss measures were found in men compared with women (r = 0.55-0.59 for men; r = 0.12-0.49 for women). CONCLUSION: In response to eccentric exercise, women experienced greater immediate strength loss than men and were more likely to be high responders for immediate strength loss; men experienced greater serum CK activity than women and were more likely to be high responders for increased serum CK. Although the explanation for high responders to eccentric exercise remains unknown, we have shown that there are sex-specific differences in CK and strength-loss response after eccentric exercise.     

Muscle damage and soreness after endurance exercise of the elbow flexors

PURPOSE: This study investigated changes in indirect markers of muscle damage after endurance exercise of the elbow flexors and compared the changes with those after maximal eccentric actions (Max-ECC) of the elbow flexors. METHODS: Eighteen male students rhythmically lifted (1 s) and lowered (1 s) a light dumbbell (1.1-1.8 kg: 9% of MIF) in 60-180 degrees of elbow joint angle for 2 h (2-h Ex). Maximal isometric force (MIF), relaxed (RANG) and flexed elbow joint angles (FANG), upper-arm circumference (CIR), muscle soreness (SOR), B-mode ultrasound (US), and plasma creatine kinase (CK) activity were assessed before and immediately after, and up to 96 h after exercise. RESULTS: All measures were altered significantly (P < 0.05) after 2-h Ex in a similar time course to Max-ECC; however, changes in RANG, FANG, CIR, US, and CK (peak: 356 +/- 121 IU.L-1) were significantly (P < 0.05) smaller compared with those after Max-ECC. SOR developed immediately after 2-h Ex and peaked 24-48 h after exercise. MIF dropped to 44.1% of the preexercise level, which was significantly (P < 0.05) lower than that after Max-ECC (58.1%), immediately postexercise. MIF recovered to 79.8% at 24 h, and 97.8% at 96 h postexercise, which was a significantly (P < 0.05) faster recovery compared with that of Max-ECC (73.1% at 96 h). CONCLUSION: These results showed low-intensity continuous muscle contractions (3600 times) resulted in muscle damage; however, the magnitude of the muscle damage was less severe, and the recovery was faster compared with 12 maximal eccentric muscle actions.     

Unilateral eccentric exercise of the knee flexors affects muscle activation during gait

Uni-lateral muscle soreness is common yet the effects on gait or electromyographic (EMG) activity are unknown. The purpose of our study was to induce delayed onset muscle soreness (DOMS) in the knee flexor group and measure the resultant change in EMG activity and knee motion during gait. Nine healthy subjects participated in the study. Measures of function, evoked tenderness of the biceps femoris, as well as knee angle, and EMG activity during gait were assessed prior and 48 h after an eccentric exercise protocol. DOMS was induced unilaterally in the knee flexors using an isokinetic dynamometer and subjects exercised until they could not generate 50% of their maximal voluntary isometric contraction (MVIC). There was a significant decrease in biceps femoris activity after DOMS during the last phase of gait. Moreover, there was a day × phase interaction for gastrocnemius activity with the last two phases displaying an increase in activity. There was no significant change in knee angle during gait. The decrease in biceps femoris activity as well as the increase in gastrocnemius activity could be evidence of a protective mechanism designed to decrease activity of the sore muscle while increasing the activity of a synergistic muscle.     

中医外治法对肘屈肌连续离心训练作功及力矩的影响

为观察中医药外治法对连续离心训练引起的延迟性肌肉酸痛 (DOMS)恢复的作用 ,采用计算机采控的离心训练设备对受试者进行连续 7天伸肘训练产生DOMS ,同时辅以推拿、牵拉、热水浴、盐水浴、中药浴等恢复手段 ,观察屈肘肌作功和力矩等力学指标。结果发现 ,连续 7天离心训练对DOMS产生后肌力的恢复没有明显影响 ,推拿、牵拉、中药浴等手段对DOMS后肌肉力矩和作功有明显的促进恢复的作用。     

Homoeopathy for delayed onset muscle soreness: a randomised double blind placebo controlled trial.

OBJECTIVE: To pilot a model for determining whether a homoeopathic medicine is superior to placebo for delayed onset muscle soreness (DOMS). DESIGN: Randomised double blind placebo controlled trial. SETTING: Physiotherapy department of a homoeopathic hospital. SUBJECTS: Sixty eight healthy volunteers (average age 30; 41% men) undertook a 10 minute period of bench stepping carrying a small weight and were randomised to a homoeopathic medicine or placebo. OUTCOME MEASURES: Mean muscle soreness in the five day period after the exercise test, symptom free days, maximum soreness score, days to no soreness, days on medication. RESULTS: The difference between group means was 0.17 in favour of placebo with 95% confidence intervals +/- 0.50. Similar results were found for other outcome measures. CONCLUSION: The study did not find benefit of the homoeopathic remedy in DOMS. Bench stepping may not be an appropriate model to evaluate the effects of a treatment on DOMS because of wide variation between subject soreness scores.     

Delayed onset muscle soreness does not alter O2 uptake kinetics during heavy-intensity cycling in humans

The purpose of this study was to determine if exercise-induced delayed onset muscle soreness (DOMS) would alter O2 uptake kinetics during heavy cycling in 9 untrained females. O2 uptake kinetics were characterised during 8-min of constant-load cycling performed with and without DOMS. DOMS was caused by completing 30 min of bench-stepping at a rate of 15 steps.min(-1). Two days after bench stepping, all subjects reported significant leg muscle soreness. Both phase II kinetics (without DOMS tau1: 26.6 +/- 2.4 s; with DOMS tau1: 27.2 +/- 3.7 s) and the slow component amplitude (without DOMS: 277 +/- 15 mL.min(-1); with DOMS: 291 +/- 21 mL.min(-1)) were unaffected by DOMS. The change in blood lactate concentration from rest to end-exercise was significantly greater during exercise performed with DOMS. Eccentric exercise causing a moderate degree of DOMS does not appear to impact upon the mechanisms mediating phase II or the slow component of O2 uptake kinetics.     

Sensory level electrical muscle stimulation: effect on markers of muscle injury

Background: Monophasic high voltage stimulation (MHVS) is widely prescribed for the treatment of inflammation associated with muscle injury. However, limited scientific evidence exists to support its purported benefits in humans.

Objective: To examine the efficacy of early initiation of MHVS treatment after muscle injury.

Methods: In a randomised, cross over design, 14 men performed repetitive eccentric contractions of the elbow flexor muscles followed by either MHVS or control treatment. MHVS treatments were applied five minutes and 3, 6, 24, 48, 72, 96, and 120 hours after eccentric contractions.

Results: MHVS resulted in a significant reduction (p<0.05) in delayed onset muscle soreness 24 hours after eccentric exercise compared with controls. Elbow extension was significantly increased immediately after administration of MHVS compared with controls. No significant differences were observed between MHVS treatment and controls for maximal isometric strength, flexed arm angle, or arm volume.

Conclusions: Early and frequent application of MHVS may provide transient relief from delayed onset muscle soreness and short term improvements in range of motion after injurious exercise. However, MHVS treatment may not enhance recovery after muscle injury because of lack of improvements in strength and active range of motion.

     

A COX-2 inhibitor reduces muscle soreness, but does not influence recovery and adaptation after eccentric exercise

The aim of this study was to investigate the effect of a cyclooxygenase (COX)-2 inhibitor on the recovery of muscle function, inflammation, regeneration after, and adaptation to, unaccustomed eccentric exercise. Thirty-three young males and females participated in a double-blind, placebo-controlled experiment. Seventy unilateral, voluntary, maximal eccentric actions with the elbow flexors were performed twice (bouts 1 and 2) with the same arm, separated by 3 weeks. The test group participants were administered 400 mg/day of celecoxib for 9 days after bout 1. After both bouts 1 and 2, concentric and isometric force-generating capacity was immediately reduced (∼40–50%), followed by the later appearance of muscle soreness and increased serum creatine kinase levels. Radiolabelled autologous leukocytes (detected by scintigraphy) and monocytes/macrophages (histology) accumulated in the exercised muscles, simultaneously with increased satellite cell activity. These responses were reduced and recovery was faster after bout 2 than 1, demonstrating a repeated-bout effect. No differences between the celecoxib and placebo groups were detected, except for muscle soreness, which was attenuated by celecoxib. In summary, celecoxib, a COX-2 inhibitor, did not detectably affect recovery of muscle function or markers of inflammation and regeneration after unaccustomed eccentric exercise, nor did the drug influence the repeated-bout effect. However, it alleviated muscle soreness.