The isolated and combined effects of selected physical activity and ibuprofen on delayed-onset muscle soreness

NSAIDs do not prevent exercise-induced performance deficits or alleviate muscle soreness: A placebo-controlled randomized, double-blinded, cross-over study

Non-steroidal anti-inflammatory drugs (NSAIDs) are frequently consumed by athletes to manage muscle soreness, expedite recovery, or improve performance. Despite the prevalence of NSAID use, their effects on muscle soreness and performance, particularly when administered prophylactically, remain unclear. This randomized, double-blind, counter-balanced, crossover study examined the effect of consuming a single dose of each of three NSAIDs (celecoxib, 200 mg; ibuprofen, 800 mg; flurbiprofen, 100 mg) or placebo 2 h before on muscle soreness and performance following an acute plyometric training session. Twelve healthy adults, aged 18-42 years, completed a standardized plyometric exercise session consisting of 10 sets of 10 repetitions at 40 % 1-repetition maximum (1RM) on a leg press device. During exercise, total work, rating of perceived exertion, and heart rate were measured. Maximum voluntary contraction force (MVC), vertical jump height, and muscle soreness were measured before exercise and 4-h and 24-h post-exercise. We found no significant differences in total work, heart rate, or rating of perceived exertion between treatments. Additionally, no significant differences in muscle soreness or vertical jump were observed between treatments. Ibuprofen and flurbiprofen did not prevent decrements in MVC, but celecoxib attenuated decreases in MVC 4-h post exercise (p < 0.05). This study suggests that athletes may not benefit from prophylactic ibuprofen or flurbiprofen treatment to prevent discomfort or performance decrements associated with exercise, but celecoxib may mitigate short-term performance decrements.

Neurochemical mechanism of muscular pain: Insight from the study on delayed onset muscle soreness

We reviewed fundamental studies on muscular pain, encompassing the characteristics of primary afferent fibers and neurons, spinal and thalamic projections, several muscular pain models, and possible neurochemical mechanisms of muscle pain. Most parts of this review were based on data obtained from animal experiments, and some researches on humans were also introduced. We focused on delayed-onset muscle soreness (DOMS) induced by lengthening contractions (LC), suitable for studying myofascial pain syndromes. The muscular mechanical withdrawal threshold (MMWT) decreased 1-3 days after LC in rats. Changing the speed and range of stretching showed that muscle injury seldom occurred, except in extreme conditions, and that DOMS occurred in parameters without muscle damage. The B2 bradykinin receptor-nerve growth factor (NGF) route and COX-2-glial cell line-derived neurotrophic factor (GDNF) route were involved in the development of DOMS. The interactions between these routes occurred at two levels. A repeated-bout effect was observed in MMWT and NGF upregulation, and this study showed that adaptation possibly occurred before B2 bradykinin receptor activation. We have also briefly discussed the prevention and treatment of DOMS.

ANTI-INFLAMMATORIES FOR DELAYED ONSET MUSCLE SORENESS: SYSTEMATIC REVIEW AND META-ANALYSIS

ABSTRACT Objective: To investigate the effectiveness of pharmacological interventions in the treatment of delayed onset muscle soreness (DOMS). Design: A systematic review and meta-analysis of randomized controlled clinical trials (RCTs). Data sources: The PubMed/MEDLINE, EMBASE, SPORTDiscus, Scielo and Cochrane Central Register of Controlled Trials (CENTRAL) databases were searched for RCTs published prior to August 3, 2020. Eligibility criteria for selecting studies: Studies that 1) used an RCT design; 2) evaluated the effectiveness of steroidal or nonsteroidal anti-inflammatory drugs (NSAIDs) in treating DOMS; and 3) therapeutically used drugs after exercise were included. Results: In total, 26 studies (patients = 934) were eligible for inclusion in the qualitative analysis on the treatment of DOMS. The results of the meta-analysis showed no superiority between the use and non-use of NSAIDs in the improvement of late muscle pain, as no statistically significant differences were verified (21 studies, n= 955; standard mean difference (SMD)= 0.02; 95% confidence interval (CI) −0.58, 0.63; p=0.94; I2=93%). The quality of the synthesized evidence was very low according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria, and there was significant heterogeneity among the included studies. Conclusion: The results demonstrate that NSAIDs are not superior to controls/placebos in treating DOMS. The inclusion of both studies with dose-response protocols and those with exercise protocols may have influenced the results. In addition, the high risk of bias identified reveals that limitations need to be considered when interpreting the results. Level of evidence I; ystematic review of RCT (Randomized and Controlled Clinical Trials).

Effect of Non-Steroidal Anti-Inflammatory Drugs on Sport Performance Indices in Healthy People: a Meta-Analysis of Randomized Controlled Trials

Background

Non-steroidal anti-inflammatory drugs (NSAIDs) are medications that are frequently used by athletes. There may also be some abuse of these substances, although it is unclear whether NSAIDs in fact enhance performance.

We performed a systematic review and meta-analysis to evaluate the effect of NSAIDs on sport performance indices.

Methods

We selected randomized trials from the PubMed and Cochrane Library databases investigating the effects of NSAIDs on sport performance. Volunteers could be healthy adult men and women. Any NSAID, administered by any route, taken prior to any type of exercise, and for any duration could be used. The control intervention could be a placebo, an active substance, or no intervention. We included double-blind, single-blind, and open-label studies. The primary outcome was the maximum performance in exercises as defined in each study. The secondary outcomes were the time until self-reported exhaustion and the self-reported pain.

Results

Among 1631 records, we retained thirteen parallel-group and ten crossover studies, totaling 366 and 148 subjects, respectively. They were disparate regarding treatments, dose and duration, and the type of exercise. There was neither significant difference in the maximum performance between NSAIDs and control groups nor in the time until exhaustion nor in self-perceived pain.

Conclusions

The existence of an ergogenic effect of NSAIDs on sport performance indices was unable to be concluded, since the level of evidence of the studies is low, the doses tested, and the exercises performed are very heterogeneous and far from those observed in real-life practices. More studies are required.

Immediate effects of transcutaneous electrical nerve stimulation (TENS) administered during resistance exercise on pain intensity and physical performance of healthy subjects: a randomized clinical trial

PURPOSE

Exercise-induced muscle pain is a self-limiting condition which impacts physical activity habits. Transcutaneous electrical nerve stimulation (TENS) promotes pain reduction and functional improvement in different pain conditions. We propose that applying TENS during exercise might reduce pain and improve physical performance. Thus, we aimed to investigate immediate effects of TENS applied during resistance exercise.

METHODS

Healthy subjects of both sexes, irregularly active or sedentary were assigned into two groups: active (n = 24) or placebo (n = 22) TENS. The study was conducted over five moments: on day 0, subjects were recruited, on day 1 subjects performed the one-repetition maximum test (1RM); 72 h later, on day 2, 1RM was retested; 48 h later, on day 3, TENS was applied during a functional-resisted exercise protocol for upper limbs (bench press and rowing), with an intensity of 80% of 1RM; and 24 h after, on day 4, subjects were reevaluated. Assessment included pain intensity at rest and with movement, pressure pain thresholds, and muscle fatigue.

RESULTS

TENS did not reduce pain intensity when compared to placebo (p > 0.05). TENS reduce PPT in the latissmus dorsi: p = 0.02 and anterior tibialis: p = 0.04 in immediate reassessment. Immediate effects of TENS were significant for fatigue perception at rest (p = 0.01) and number of maximum repetitions during exercise sets, starting from the 5th set of rowing exercise (p = 0.002).

CONCLUSION

Our results show that TENS did not reduce pain perception in healthy individuals, but its use induced increased muscle action, contributing to a greater fatigue perception.

Effect of NSAIDs on Recovery From Acute Skeletal Muscle Injury: A Systematic Review and Meta-analysis

BACKGROUND

There is debate as to whether the use of nonsteroidal anti-inflammatory drugs (NSAIDs) is beneficial after acute skeletal muscle injury. Some studies have suggested that NSAID use may be detrimental to injured muscle.

PURPOSE

To determine whether NSAID use affects recovery from skeletal muscle injury as assessed by strength loss, soreness, and/or blood creatine kinase level.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

An extensive systematic review was completed searching 16 databases (eg, PubMed, Cochrane Library, EMBASE). Inclusion criteria were (1) acute injury to skeletal muscle, (2) use of a control condition, (3) certainty of the NSAID dose administered, and (4) use of 1 or more of the 3 desired outcome measures. A total of 5343 study reports were screened, of which 41 studies were deemed suitable for inclusion. The standardized mean difference was used as the effect size (ES) and was calculated such that a positive ES indicated NSAID efficacy. Meta-analyses were run using a random-effects model.

RESULTS

For all studies, time points after injury, and injury markers combined, NSAID use was found to elicit a small to medium, significant decrease in the markers of injury (overall ES = +0.34; P = .0001). Because heterogeneity in study ES was apparent (ie, Q- df = 52.4, P = .000005; I² = 57%), subgroup meta-analyses and meta-regressions were run in an attempt to explain the heterogeneity. In human studies, study ESs were higher when lower body muscles were injured ( P = .045). In animal studies, study ESs were lower with longer NSAID administration durations ( P = .023) and at longer follow-up times after injury ( P = .010).

CONCLUSION

Overall, our analysis supports NSAID use for reducing strength loss, soreness, and blood creatine kinase level after an acute muscle injury, at least for humans and in the short term. Additional research is required to determine why NSAID use appears to be more effective when lower-body muscles in humans are injured. It would also be important to determine why NSAID use appears detrimental at later times after injury in animals but not humans.

Anti-inflammatory interventions and skeletal muscle injury: benefit or detriment?

Exercise, eccentric contractions, acute trauma, and disease are all causal mechanisms of skeletal muscle injury. After skeletal muscle is injured, it undergoes sequential phases of degeneration, inflammation, regeneration, and fibrosis. Events that occur in response to inflammation trigger regenerative processes. However, since inflammation causes pain, decreases skeletal muscle function, has a negative effect on performance, and contributes to fibrosis, which is one of the leading causes of delayed regeneration, the general practice has been to reduce inflammation. The problem with this approach is that preventing inflammation may hinder recovery. Current treatment options for inflammation are not necessarily effective and, in some cases, they may be unsafe. This review focuses on the question of whether the most beneficial course of treatment should be to block inflammation or if it is sensible to allow inflammatory processes to progress naturally. If blocking inflammation is perceived as a beneficial approach, it is not yet known at what time point during the inflammatory response it is most sensible to interfere. To address these issues, this review evaluates the effects of various anti-inflammatory agents on recovery processes in response to exercise-induced, traumatic, and disease-associated models of skeletal muscle injury. A collective analysis such as this should lay the foundation for future work that systematically manipulates the inflammatory response to most effectively promote regeneration and functional recovery in injured skeletal muscle, while reducing the negative effects of inflammatory processes such as pain and fibrosis.

Upregulated glial cell line-derived neurotrophic factor through cyclooxygenase-2 activation in the muscle is required for mechanical hyperalgesia after exercise in rats

Unaccustomed strenuous exercise that includes lengthening contraction (LC) often causes delayed onset muscle soreness (DOMS), characterised as muscular mechanical hyperalgesia. Previously we reported that a bradykinin-like substance released from the muscle during exercise plays a pivotal role in triggering the process of muscular mechanical hyperalgesia by upregulating nerve growth factor (NGF) in exercised muscle of rats. We show here that cyclooxygenase (COX)-2 and glial cell line-derived neurotrophic factor (GDNF) are also involved in DOMS. COX-2 inhibitors but not COX-1 inhibitors given orally before LC completely suppressed the development of DOMS, but when given 2 days after LC they failed to reverse the mechanical hyperalgesia. COX-2 mRNA and protein in exercised muscle increased six- to 13-fold in mRNA and 1.7-2-fold in protein 0-12 h after LC. COX-2 inhibitors did not suppress NGF upregulation after LC. Instead, we found GDNF mRNA was upregulated seven- to eight-fold in the exercised muscle 12 h-1 day after LC and blocked by pretreatment of COX-2 inhibitors. In situ hybridisation studies revealed that both COX-2 and GDNF mRNA signals increased at the periphery of skeletal muscle cells 12 h after LC. The accumulation of COX-2 mRNA signals was also observed in small blood vessels. Intramuscular injection of anti-GDNF antibody 2 days after LC partly reversed DOMS. Based on these findings, we conclude that GDNF upregulation through COX-2 activation is essential to mechanical hyperalgesia after exercise.

A randomized, placebo-controlled trial of acetaminophen extended release for treatment of post-marathon muscle soreness

OBJECTIVE

To compare the efficacy of acetaminophen extended release (ER) caplets to placebo in treating muscle soreness after a marathon.

METHODS

This was a randomized, double-blind, placebo-controlled study of participants ≥ 18 years old, who completed a marathon and experienced muscle soreness rated at least 4 on a 0-to-10 numerical rating scale. The intent-to-treat efficacy analysis included 610 participants. Participants were screened for eligibility before the marathon, and reported to the study tent after the marathon. On confirming eligibility, participants were randomly assigned to 4 days of 3-times-daily treatment of either acetaminophen ER 1300 mg (n=307) or placebo (n=303).

RESULTS

Participants treated with acetaminophen ER reported a significantly (P<0.0001) greater decrease in the primary endpoint of average change from baseline in muscle soreness on the day of the marathon (day 1) (-0.79) than did placebo (-0.36). In addition, the adjusted mean average interference with sleep was significantly lower for acetaminophen ER (2.14) than for placebo (2.52, P=0.0046). The adjusted mean overall satisfaction with treatment was significantly higher for acetaminophen ER (5.38) than for placebo (4.64, P=0.0060). Adverse events were reported by 3.7% of participants, with no clinically important difference between treatment groups. No serious adverse events were reported.

CONCLUSIONS

Acetaminophen ER 1300 mg, a nonprescription drug, was an effective treatment for post-race muscle soreness on the day of the marathon. In addition, acetaminophen ER provided benefit for interference with sleep and overall satisfaction with treatment, and was generally well tolerated.

Effect of the use of carprofen in dogs undergoing intense rehabilitation after lateral fabellar suture stabilization

OBJECTIVE

To determine whether carprofen, a commercially available NSAID, would decrease perceived exertion and signs of pain in dogs and therefore increase muscle mass and hind limb function without decreasing range of motion after lateral fabellar suture stabilization.

DESIGN

Randomized, blinded, controlled clinical trial.

ANIMALS

35 dogs with cranial cruciate ligament rupture and lateral fabellar suture stabilization followed by rehabilitation.

PROCEDURES

All dogs underwent surgical stabilization of cranial cruciate ligament rupture by placement of a lateral fabellar suture. Dogs received carprofen (2.2 mg/kg [1 mg/lb], PO, q 12 h) for the first 7 days after surgery and underwent concentrated rehabilitation exercises during weeks 3, 5, and 7 after surgery. Eighteen dogs also received carprofen (2.2 mg/kg, PO, q 12 h) during the weeks of concentrated rehabilitation. Outcomes were measured by a single investigator, who was blinded to group assignments, using pressure platform gait analysis, goniometry, thigh circumference, and mean workout speed at a consistent level of exertion.

RESULTS

There were no differences between the 2 groups in ground reaction forces, thigh circumference, or exertion (mean workout speed) over time or at any individual time point. However, both groups improved significantly over time for all outcome measures.

CONCLUSIONS AND CLINICAL RELEVANCE

Providing carprofen to dogs during concentrated rehabilitation after lateral fabellar suture stabilization did not improve hind limb function, range of motion, or thigh circumference, nor did it decrease perceived exertion, compared with control dogs. Carprofen was not a compulsory component of a physical therapy regimen after lateral fabellar suture stabilization.

Stretching to prevent or reduce muscle soreness after exercise

BACKGROUND

Many people stretch before or after engaging in athletic activity. Usually the purpose is to reduce risk of injury, reduce soreness after exercise, or enhance athletic performance. This is an update of a Cochrane review first published in 2007.

OBJECTIVES

The aim of this review was to determine effects of stretching before or after exercise on the development of delayed-onset muscle soreness.

SEARCH STRATEGY

We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (to 10 August 2009), the Cochrane Central Register of Controlled Trials (2010, Issue 1), MEDLINE (1966 to 8th February 2010), EMBASE (1988 to 8th February 2010), CINAHL (1982 to 23rd February 2010), SPORTDiscus (1949 to 8th February 2010), PEDro (to 15th February 2010) and reference lists of articles.

SELECTION CRITERIA

Eligible studies were randomised or quasi-randomised studies of any pre-exercise or post-exercise stretching technique designed to prevent or treat delayed-onset muscle soreness (DOMS). For the studies to be included, the stretching had to be conducted soon before or soon after exercise and muscle soreness had to be assessed.

DATA COLLECTION AND ANALYSIS

Risk of bias was assessed using The Cochrane Collaboration's 'Risk of bias' tool and quality of evidence was assessed using GRADE. Estimates of effects of stretching were converted to a common 100-point scale. Outcomes were pooled in fixed-effect meta-analyses.

MAIN RESULTS

Twelve studies were included in the review. This update incorporated two new studies. One of the new trials was a large field-based trial that included 2377 participants, 1220 of whom were allocated stretching. All other 11 studies were small, with between 10 and 30 participants receiving the stretch condition. Ten studies were laboratory-based and other two were field-based. All studies were exposed to either a moderate or high risk of bias. The quality of evidence was low to moderate.There was a high degree of consistency of results across studies. The pooled estimate showed that pre-exercise stretching reduced soreness at one day after exercise by, on average, half a point on a 100-point scale (mean difference -0.52, 95% CI -11.30 to 10.26; 3 studies). Post-exercise stretching reduced soreness at one day after exercise by, on average, one point on a 100-point scale (mean difference -1.04, 95% CI -6.88 to 4.79; 4 studies). Similar effects were evident between half a day and three days after exercise. One large study showed that stretching before and after exercise reduced peak soreness over a one week period by, on average, four points on a 100-point scale (mean difference -3.80, 95% CI -5.17 to -2.43). This effect, though statistically significant, is very small.

AUTHORS' CONCLUSIONS

The evidence from randomised studies suggests that muscle stretching, whether conducted before, after, or before and after exercise, does not produce clinically important reductions in delayed-onset muscle soreness in healthy adults.

Effects of ibuprofen topical gel on muscle soreness

PURPOSE

Muscle soreness is a common symptom after novel exercise and may influence exercise adherence. This study examined the effect of an ibuprofen topical gel and the effect of age and sex on muscle soreness after a gym exercise.

METHODS

One hundred and six participants completed six sets of 10 repetitions of the elbow and knee flexor muscles. Thirty-six hours after exercise, participants were randomized to apply an ibuprofen topical gel or placebo treatment to the affected muscle groups. Soreness evaluations were taken each hour for the first 6 h (36-42 h), then at 48, 60, 66, 72, 84, 90, 96, and 108 h after exercise. Subjects then returned to the laboratory after 3 wk and repeated the same study protocol with the opposite arm/leg and treatment.

RESULTS

We found no significant differences in soreness between the active ibuprofen gel and the placebo treatment and no difference in effectiveness between men and women or between older and younger subjects. For the placebo groups, there was no sex differences in muscle soreness; however, when the data were analyzed by dividing participants into young (18-29 yr) and old (40-65 yr) cohort, the old cohort reported significantly less soreness in response to the elbow flexion exercise than the young cohort (P < 0.01).

CONCLUSION

The results of this study suggest that the topical application of ibuprofen is not an effective treatment for muscle soreness after an unaccustomed gym exercise. Furthermore, our results show that there is no sex difference in the soreness response and that older subjects have less soreness in response to a similar exercise stimulus as young subjects.

The effects of ingestion of omega-3 fatty acids on perceived pain and external symptoms of delayed onset muscle soreness in untrained men

OBJECTIVE

The purpose of this study was to examine the effect of ingestion of omega-3 on perceived pain and external symptoms of delayed onset muscle soreness after eccentric exercise in knee extensors.

DESIGN

A randomized, double-blinded, repeated measures design was used for this study.

SETTING

The study was performed in the Exercise Physiology Laboratory at the Faculty of Humanities of Urmia University.

PARTICIPANTS

Twenty-seven men, who had not participated in any training program 60 days before their participation in this study, were recruited. All subjects finished the study.

INTERVENTIONS

Knee range of motion (ROM), perceived pain, and thigh circumference of the right leg were taken before, immediately, and after 24 and 48 hours after an eccentric exercise. Subjects were assigned to one of the experimental (1.8 g/d omega-3), placebo (R.P. Scherer), or control groups.

MAIN OUTCOME MEASURES

Subjects self-reported the perceived pain level of the lower limbs using the Talag mentally corrected scale. Thigh circumference was measured by using a Gulick anthropometric tape. Knee ROM was determined by using a Jamar goniometer.

RESULTS

No differences among treatments were observed for pain and ROM before, immediately, and 24 hours after the exercise. However, observed differences in perceived pain and ROM were obvious at 48 hours postexercise. In the case of thigh circumference, differences were at 24 and 48 hours postexercise, and there was no difference before and immediately after exercise.

CONCLUSIONS

Ingestion of omega-3 can be effective in ameliorating delayed onset muscle soreness induced by eccentric exercise.

Effect of stretching on strength loss and pain after eccentric exercise

PURPOSE

The purposes of the this study were to determine whether stretch-induced strength loss was muscle length dependent (study 1) and whether passive stretching prior to eccentric exercise affected strength loss and pain on subsequent days (study 2).

METHODS

For study 1, knee flexion strength was measured isometrically (six angles) and isokinetically (eccentric and concentric) in 10 men (33 +/- 9 yr). The subjects then performed six 90-s static hamstring stretches, after which isometric and isokinetic strength were retested. For study 2, the dominant and nondominant legs of eight men (34 +/- 9 yr) were assigned to a stretch (six 60-s stretches) or control condition prior to eccentric hamstring exercise. Isometric strength and pain were assessed prior to, immediately after, and on the 3 d after exercise.

RESULTS

After stretching, strength was decreased by 17% at 80 degrees , 11% at 65 degrees , 5% at 50 degrees , 7% at 35 degrees , and 8% at 20 degrees , and it was increased by 6% at 5 degrees (angle effect P < 0.01). Strength loss following eccentric exercise was less on the stretched versus the unstretched control limb at 37 degrees (P < 0.05), but not at other angles (stretch by time by angle P < 0.01). Pain was not different between the stretched and the unstretched control limb (P = 0.94).

CONCLUSION

Stretch-induced strength loss was dependent on muscle length, such that strength was decreased with the muscle group in a shortened position, but not with the muscle group in a lengthened position. Strength loss and pain after eccentric exercise were generally unaffected by prior stretching, with the exception that stretching prevented strength loss when assessed with the muscle in a lengthened position.

Stretching to prevent or reduce muscle soreness after exercise

BACKGROUND

Many people stretch before or after (or both) engaging in athletic activity. Usually the purpose is to reduce risk of injury, reduce soreness after exercise, or enhance athletic performance.

OBJECTIVES

The aim of this review was to determine effects of stretching before or after exercise on the development of post-exercise muscle soreness.

SEARCH STRATEGY

We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (to April 2006), the Cochrane Central Register of Controlled Trials (The Cochrane Library 2006, Issue 2), MEDLINE (1966 to May 2006), EMBASE (1988 to May 2006), CINAHL (1982 to May 2006), SPORTDiscus (1949 to May 2006), PEDro (to May 2006) and reference lists of articles.

SELECTION CRITERIA

Eligible studies were randomised or quasi-randomised studies of any pre-or post-exercise stretching technique designed to prevent or treat delayed-onset muscle soreness (DOMS), provided the stretching was conducted soon before or soon after exercise. To be eligible studies must have assessed muscle soreness or tenderness.

DATA COLLECTION AND ANALYSIS

Methodological quality of the studies was assessed using the Cochrane Bone, Joint and Muscle Trauma Group's methodological quality assessment tool. Estimates of effects of stretching were converted to a common 100-point scale. Outcomes were pooled in a fixed-effect meta-analysis.

MAIN RESULTS

Of the 10 included studies, nine were carried out in laboratory settings using standardised exercise protocols and one involved post-exercise stretching in footballers. All participants were young healthy adults. Three studies examined the effects of stretching before exercise and seven studies investigated the effects of stretching after exercise. Two studies, both of stretching after exercise, involved repeated stretching sessions at intervals of greater than two hours. The duration of stretching applied in a single session ranged from 40 to 600 seconds. All studies were small (between 10 and 30 participants received the stretch condition) and of questionable quality. The effects of stretching reported in individual studies were very small and there was a high degree of consistency of results across studies. The pooled estimate showed that pre-exercise stretching reduced soreness one day after exercise by, on average, 0.5 points on a 100-point scale (95% CI -11.3 to 10.3; 3 studies). Post-exercise stretching reduced soreness one day after exercise by, on average, 1.0 points on a 100-point scale (95% CI -6.9 to 4.8; 4 studies). Similar effects were evident between half a day and three days after exercise.

AUTHORS' CONCLUSIONS

The evidence derived from mainly laboratory-based studies of stretching indicate that muscle stretching does not reduce delayed-onset muscle soreness in young healthy adults.