Recovery and soreness
Everything in the library studied for it, medical and holistic together. Within each kind, what was shown to help comes first, strongest evidence first. What was tested and not shown to help stays on the list.
Strong several reviews agree · Moderate one review or consistent trials · Limited one or a few small studies · Untested no study in people, listed with what it rests on
Medication
Soreness and strength loss after muscle injury
Shown to reduce strength loss, soreness and creatine kinase modestly after acute muscle injury, more for lower body muscles, in studies including animals.
The numbers and sources
- Effect
- Across injury markers combined, NSAIDs produced a small to medium decrease (standardized effect size +0.34) in strength loss, soreness and blood creatine kinase after acute muscle injury. The effect was larger when lower body muscles were injured [1].
- Population
- 41 studies of acute skeletal muscle injury, human and animal, including exercise-induced damage [1].
- Sources
- [1]
- Caveats
- Heterogeneity was moderate (I² 57%). The pooled result includes animal studies, and in animals the effect fell with longer use and longer follow-up [1].
Peptides and SARMs
Tendon and ligament healing
Not studied in people. Animal studies found faster healing of cut tendons and ligaments in rats, from a handful of research groups.
No study in people. This rests on animal studies, lab studies.
The numbers and sources
- Effect
- A 2019 review found that studies of BPC-157 reported consistent healing effects on tendon, ligament and skeletal muscle, mostly in small rodent models, from a handful of research groups [15]. A 2025 systematic review included 35 preclinical studies and found that BPC-157 improved functional, structural and biomechanical outcomes in tendon, ligament, muscle and bone injuries in those models [16]. After the medial collateral ligament of the knee was cut in rats, BPC-157 given by injection, in drinking water or as a cream improved functional, biomechanical, macroscopic and microscopic healing over 90 days [17]. In the lab, it sped the outgrowth of fibroblasts from rat Achilles tendon tissue, raised their survival under oxidative stress and increased their migration, without directly changing how fast they multiplied [18]. In a 2026 study, rats given BPC-157 after Achilles tendon repair had a higher load to failure and lower tendon damage scores than controls at 4 weeks, but neither difference was statistically significant [19].
- Population
- Rats, and tendon cells from rats in the lab [15][16][17][18]. 32 rats in the 2026 study [19].
- Sources
- [15], [16], [17], [18], [19]
- Caveats
- The 2019 review notes that efficacy has not been confirmed in humans [15]. Surgically cut tendons and ligaments in rats do not show what happens in people. A 2026 review found no controlled human orthopaedic evidence for BPC-157 [10].
Muscle injury
Not studied in people. Animal studies found faster recovery of cut and crushed leg muscles in rats.
No study in people. This rests on animal studies.
The numbers and sources
- Effect
- In rats whose quadriceps muscle was cut through, BPC-157 given by injection improved load to failure, walking recovery, muscle fiber regeneration and the muscle's appearance over 72 days [20]. In rats with a crushed calf muscle, BPC-157 given by injection or as a cream over 14 days reduced bruising and swelling and improved function, microscopic healing and muscle enzyme levels [21]. A 2019 review found that skeletal muscle injury models suggested a benefit after direct trauma [15].
- Population
- Rats [15][20][21].
- Sources
- [20], [21], [15]
- Caveats
- The two injury studies come from the same research group [20][21]. Cut and crushed muscles in rats do not show what happens after a muscle strain in people. The human studies located concerned knee pain, interstitial cystitis and intravenous safety [9].
Tendon healing
Not studied in people. One rat study found stronger repaired Achilles tendons and better tissue scores after 4 weeks of TB-500.
No study in people. This rests on animal studies.
The numbers and sources
- Effect
- In rats whose Achilles tendon was cut and repaired, those given TB-500 for 4 weeks had a higher maximum load to failure than controls, a statistically significant difference, and lower total tendon damage scores on two microscopic scoring scales. Adding BPC-157 to TB-500 gave no further benefit over either alone [15]. A 2026 review found that direct musculoskeletal evidence for full-length thymosin beta-4 is limited to lab and rodent studies, and that TB-500 has no validated equivalence with it [9].
- Population
- 32 male rats, 8 in each of four groups [15].
- Sources
- [15], [9]
- Caveats
- One small study, which its authors describe as exploratory and preliminary [15]. Surgically cut tendons in rats do not show what happens in people. FDA found no clinical studies of TB-500 by any route [3].
Injury recovery
We haven't sourced research on this yet.
Injury recovery
We haven't sourced research on this yet.
Muscle healing
We haven't sourced research on this yet.
Supplements
Muscle soreness and damage after hard exercise
Shown to reduce muscle soreness 24 to 96 hours after damaging exercise in active adults, with larger effects at higher doses and longer use.
The numbers and sources
- Effect
- Across 18 RCTs, BCAAs reduced soreness at 24 hours (g -1.34), 48 hours (g -1.75), 72 hours (g -1.82) and 96 hours (g -0.82). Creatine kinase was lower immediately (g -0.44) and at 72 hours (g -0.99), but not at 24, 48 or 96 hours; LDH did not change. Higher daily and total doses and longer use were linked to larger effects [4]. A second meta-analysis of 9 RCTs found reduced soreness 24 to 72 hours after exercise, mainly in trained people with mild to moderate damage, at doses up to 255 mg per kg a day [5].
- Population
- Healthy active adults after damaging resistance or endurance exercise [4][5].
- Sources
- [4], [5]
- Caveats
- The authors of [5] report high variability between studies by training status, dose and timing. Soreness is self-rated.
Recovery from muscle damage
Shown to speed strength and jump recovery after damaging exercise with beetroot juice, in small trials. The reviews disagree on creatine kinase.
The numbers and sources
- Effect
- In 6 pooled studies, beetroot juice sped isometric strength recovery at 72 hours (SMD 0.54) and countermovement jump recovery at 24 to 72 hours (SMD 0.75 to 1.32), and raised pressure pain threshold at 48 and 72 hours. Creatine kinase and oxidative stress did not change; C-reactive protein was higher than placebo at 48 hours (SMD 0.55) [12]. In 7 trials, beetroot juice lowered creatine kinase by 98.67 IU/L (95% CI -122.14 to -75.21, I² 74.2%) and improved recovery of isometric strength (8.93%, I² 81.2%), jump height (4.72%) and pressure pain threshold (7.22%) against placebo. CRP, IL-6 and TNF-α did not change [13].
- Population
- Adults after damaging exercise [12][13].
- Sources
- [12], [13]
- Caveats
- Both reviews pooled 6 or 7 small, overlapping trials, and heterogeneity was high for creatine kinase and strength [13]. The two disagree on creatine kinase. All pooled trials in [12] had some concerns for risk of bias and used beetroot juice rather than isolated nitrate, so other juice compounds cannot be ruled out [12].
Muscle soreness and recovery after exercise
Shown to reduce muscle soreness and improve strength after eccentric exercise in healthy adults, though the wider review called recovery effects equivocal.
The numbers and sources
- Effect
- In 9 placebo-controlled eccentric exercise trials, long-chain omega-3 reduced delayed onset muscle soreness (Hedges' g -0.75, 95% CI -1.14 to -0.36), creatine kinase (g -0.40) and swelling (g -0.45), and improved strength (g 0.45, 95% CI 0.07 to 0.83) and range of motion (g 0.93) at peak impairment. Across all 43 studies reviewed, the effect on recovery was equivocal [30].
- Population
- Healthy young to middle-aged adults [30].
- Sources
- [30]
- Caveats
- The authors note significant methodological limits and could not assess dosing. One author reports product and placebo support from AkerBiomarine, a krill oil producer [30].
Muscle damage markers
Shown to lower the muscle damage markers creatine kinase and LDH after damaging exercise in healthy adults, mainly in studies over 6 weeks.
The numbers and sources
- Effect
- Across 10 studies (324 participants), HMB lowered creatine kinase by 60.71 U/L (95% CI -78.12 to -43.29) and, across 8 studies, LDH by 15.42 U/L (95% CI -22.2 to -8.6). The effect was significant in studies longer than 6 weeks [11].
- Population
- Healthy adults after damaging exercise [11].
- Sources
- [11]
- Caveats
- Blood markers, not soreness or performance.
Muscle soreness and damage markers
Shown to lower muscle soreness for up to 96 hours after damaging exercise in adults, with damage markers lower at 24 hours only.
The numbers and sources
- Effect
- Across 7 RCTs, L-carnitine lowered muscle soreness at 0, 24, 48, 72 and 96 hours after damaging exercise, and lowered creatine kinase, myoglobin and LDH at 24 hours only [4].
- Population
- Adults after exercise-induced muscle damage [4].
- Sources
- [4]
- Caveats
- The abstract gives no effect sizes. Seven trials.
Recovery of muscle function after training
Shown to speed recovery of muscle function modestly in the 4 days after hard resistance training in young adults, with half of studies reporting benefit.
The numbers and sources
- Effect
- Across 13 RCTs from 8 studies, whey protein produced effect sizes of 0.4 to 0.7 for restoring contractile function from under 24 to 96 hours after strenuous resistance training. Half of the individual studies reported a benefit [7].
- Population
- Young, healthy adults [7].
- Sources
- [7]
- Caveats
- One meta-analysis of a small pool of trials. Funded by Food Health Ireland, a dairy research partnership [7].
Recovery after strenuous exercise
Shown to speed recovery of strength after strenuous exercise in exercising adults and athletes. Reviews disagree on whether muscle soreness falls.
The numbers and sources
- Effect
- Across 14 studies, tart cherry reduced muscle soreness (ES -0.44, 95% CI -0.87 to -0.02) and sped recovery of strength (ES -0.78, 95% CI -1.11 to -0.46) and power (ES -0.53, 95% CI -0.77 to -0.29). Creatine kinase and TNF-alpha did not change [1]. A 2026 meta-analysis of 19 trials in trained athletes found faster recovery of maximal strength at every time point (ES 0.63 right after exercise to 4.82 at 96 hours) and lower CRP up to 48 hours (ES -0.46 to -0.73). Muscle soreness, creatine kinase, IL-6 and TNF-alpha did not change [2].
- Population
- Exercising adults in 14 studies to July 2020 [1]. Trained athletes in 19 trials to December 2025 [2].
- Sources
- [1], [2]
- Caveats
- The two meta-analyses disagree on soreness, and the later one reports strength effects several times larger, with I² of 69% to 93% [1][2]. Certainty in [2] ranged from very low to moderate, and several results depended on single studies. Products, doses and exercise protocols varied.
Recovery
One small trial found 600 mg a day raised recovery and sleep quality scores in 30 female footballers over 28 days.
The numbers and sources
- Effect
- A Bayesian meta-analysis reported ashwagandha outperformed placebo on fatigue or recovery [11]. In 30 professional female footballers, 600 mg a day of root extract for 28 days raised total quality recovery scores over placebo (group by time p = 0.026) and improved perceived sleep quality (p = 0.038) [14].
- Population
- Healthy men and women [11]. 30 female footballers [14].
- Sources
- [11], [14]
- Caveats
- One small trial, whose abstract reports p values without effect sizes [14]. The Bayesian abstract does not report effect sizes [11].
Muscle soreness after exercise
Small trials found 2 g a day lowered arm muscle pain about 25% a day after eccentric exercise.
The numbers and sources
- Effect
- In two randomized, placebo-controlled experiments (34 and 40 volunteers), 2 g of raw or heat-treated ginger a day for 11 days lowered arm muscle pain 24 hours after eccentric exercise by 25% and 23% against placebo. Effects on other measures were smaller [9].
- Population
- 74 adult volunteers [9].
- Sources
- [9]
- Caveats
- One research group, one elbow-flexor exercise model.
Muscle soreness and strength recovery
One small trial found lower soreness and faster strength recovery over 72 hours after eccentric exercise in young adults.
The numbers and sources
- Effect
- In 16 young adults doing eccentric knee extensions, 0.3 g per kg a day for 72 hours gave lower soreness at 24 hours (2.8 against 3.4), 48 hours (2.6 against 3.9) and 72 hours (1.7 against 2.9), and higher fast-speed peak torque at 72 hours (91% against 86% of baseline) [2].
- Population
- 8 women and 8 men, crossover design [2].
- Sources
- [2]
- Caveats
- One small trial in one muscle group. No meta-analysis of glutamine and soreness was located.
Muscle soreness after exercise
Limited evidence: curcumin lowered soreness and muscle damage markers after hard exercise in some trials, but certainty was very low.
The numbers and sources
- Effect
- Curcumin reduced creatine kinase (WMD -48.54 IU/L, 95% CI -80.67 to -16.42) and a muscle soreness index (WMD -0.476, 95% CI -0.750 to -0.202) after muscle-damaging exercise [42]. A systematic review of 15 double-blind trials in active people and athletes found favorable results in 3 of 7 trials on soreness, recovery or fatigue, 4 of 6 on muscle damage and 4 of 8 on performance [43]. In 44 moderately active adults, 300 mg a day of a turmeric formulation for 5 days did not change soreness after downhill running, while soreness recovery from peak to 72 hours was 7.9% greater than placebo [44]. In 34 men, 1,500 mg a day of hydrolyzed curcumin was followed by greater reductions in pain, creatine kinase and IL-6 (p < 0.05), and slower muscle endurance recovery at 24 hours than 750 mg a day [45].
- Population
- Adults in RCTs of exercise-induced muscle damage [42]; active people and athletes [43]; 44 moderately active adults [44]; 34 recreationally active men [45].
- Sources
- [42], [43], [44], [45]
- Caveats
- The meta-analysis abstract does not report the number of trials or participants [42]. Certainty was very low for soreness, muscle damage and performance [43]. Soreness area under the curve, the primary outcome, did not differ from placebo [44].
Exercise performance and recovery
Mixed results: one review found better performance alongside training, while another found no gain in VO2 max, time trials or power. Reviews disagree on creatine kinase.
The numbers and sources
- Effect
- Across 24 RCTs, astaxanthin lowered creatine kinase (SMD -0.45, 95% CI -0.83 to -0.07) and lactate dehydrogenase (SMD -0.93, 95% CI -1.39 to -0.48). Malondialdehyde and IL-6 did not change. VO2 max, time-trial performance and maximal power did not improve [1]. An earlier meta-analysis found better physical performance when astaxanthin was combined with training (SMD 0.62, 95% CI 0.17 to 1.06) and higher fat oxidation [2]. A 2026 meta-analysis of 7 RCTs found lower advanced oxidation protein products after exercise (SMD -1.06, 95% CI -1.49 to -0.62, I² 48%), with no change in creatine kinase, malondialdehyde, superoxide dismutase or IL-6 [3].
- Population
- Healthy participants and athletes in 24 RCTs [1]; 346 healthy participants in 11 RCTs [2]; 188 participants in 7 RCTs [3].
- Sources
- [1], [2], [3]
- Caveats
- The first two reviews disagree on performance, and [1] and [3] disagree on creatine kinase. Heterogeneity for lactate dehydrogenase was substantial [1]. One funder of [1] is a university and company joint laboratory for skin nutrition and anti-aging.
Muscle damage markers after exercise
Mixed results: two reviews found lower creatine kinase and malondialdehyde in athletes after exercise, while a 2026 review found no change.
The numbers and sources
- Effect
- In 17 trials (440 athletes), CoQ10 lowered creatine kinase by 71.81 IU/L (95% CI -124.33 to -19.3), lactate dehydrogenase by 69.99 IU/L and the oxidative stress marker malondialdehyde by 0.61 µmol/L. Total antioxidant capacity did not change [15]. In 14 RCTs (433 participants), creatine kinase fell (SMD -1.532, 95% CI -2.856 to -0.209) and malondialdehyde fell (SMD -0.289) [13]. A 2026 review of athlete trials found malondialdehyde unchanged in its primary analysis (SMD -0.96, 95% CI -2.07 to 0.15, I² 73%), and creatine kinase, IL-6 and total antioxidant capacity unchanged [12].
- Population
- Athletes [12][15]; exercising adults [13].
- Sources
- [15], [13], [12]
- Caveats
- Sources disagree on creatine kinase. Evidence quality was low to very low [15]. These are blood markers, not measured recovery or performance.
Muscle soreness and perceived effort
Limited evidence: perceived effort and soreness at 24 hours fell in one review, while a larger review found no effect on perceived effort.
The numbers and sources
- Effect
- Across 13 articles (206 participants), citrulline lowered rating of perceived exertion (7 studies, p = 0.03) and muscle soreness at 24 hours (7 studies, p = 0.04), but not at 48 hours (p = 0.25) or 72 hours (p = 0.62). Blood lactate did not change (8 studies, p = 0.17) [4].
- Population
- Healthy adults; 8 g citrulline malate was the most common dose [4].
- Sources
- [4]
- Caveats
- The abstract reports p-values without effect sizes. The results sentence groups soreness at 24 and 48 hours as reduced, but the 48-hour p-value is 0.25 [4]. A 2026 three-level meta-analysis of citrulline malate (30 RCTs, 644 participants) found no significant pooled effect on perceived exertion, so sources disagree on effort [5].
Muscle soreness after exercise
Limited evidence: antioxidant supplements lowered soreness slightly up to 72 hours after exercise, in trials mostly at high risk of bias, not specific to vitamin C.
The numbers and sources
- Effect
- Across 50 trials of antioxidant supplements, soreness was slightly lower up to 6 hours (SMD -0.30), at 24 hours (SMD -0.13, 95% CI -0.27 to 0.00), 48 hours (SMD -0.24) and 72 hours (SMD -0.19). At 96 hours there was little difference [12].
- Population
- 1,089 participants aged 16 to 55, 88% male, in trials of several kinds of antioxidant supplements and antioxidant-rich foods [12].
- Sources
- [12]
- Caveats
- Not specific to vitamin C. 47 of 50 trials carried a high risk of bias, and all used doses above the daily amount set for the general population [12].
Recovery and muscle soreness
One trial found a topical magnesium gel did not differ from a placebo gel on soreness or strength after downhill running.
The numbers and sources
- Effect
- A topical magnesium gel applied to both thighs before and after 40 minutes of downhill running did not differ from a placebo gel on muscle soreness, knee extensor strength, creatine kinase or interleukin-6 at 24 or 48 hours [13].
- Population
- 35 healthy active adults, double-blind parallel RCT [13].
- Sources
- [13]
- Caveats
- One small trial of one commercial gel. No trial of oral magnesium on recovery was located in this search.
Muscle damage and soreness after endurance exercise
One trial found no change in muscle damage markers or pain against placebo around a half-marathon.
The numbers and sources
- Effect
- Taking 3 g a day for 21 days before a half-marathon and 2 days after did not change oxidative stress, creatine kinase, LDH, or muscle and joint pain against placebo. The MSM group had pain reductions of more than 10 mm that the authors call clinically significant [5].
- Population
- 22 healthy adults, 17 women, mean age 34 [5].
- Sources
- [5]
- Caveats
- One small trial. No time-by-treatment result reached significance [5].
Therapies
Muscle soreness after exercise
Shown to reduce muscle soreness 24 to 72 hours after strenuous exercise compared with no massage, in three meta-analyses.
Compared with no intervention [8]; control conditions the source abstracts do not describe [9][10]
The numbers and sources
- Effect
- Against no intervention, soreness was lower at 24 hours (SMD -0.61, 95% CI -1.17 to -0.05), 48 hours (SMD -1.51, 95% CI -2.24 to -0.77) and 72 hours (SMD -1.46, 95% CI -2.59 to -0.33) after intense exercise [8]. Across 99 studies of recovery techniques, massage had the largest effect on soreness and perceived fatigue [9]. Across 29 studies with 1,012 participants, massage was linked to small improvements in soreness and flexibility [10].
- Population
- 504 participants in 11 trials [8]. 99 studies of recovery methods [9]. 1,012 participants in 29 randomized studies [10].
- Sources
- [8], [9], [10]
- Caveats
- Soreness is self-rated and participants know they had a massage. The three reviews share many of the same small trials.
Recovery after knee replacement
Shown to improve function and pain modestly 3 to 4 months after knee replacement, compared with minimal physiotherapy. No long-term benefit was found.
Compared with minimal physiotherapy [13]; home-based physiotherapy [13]
The numbers and sources
- Effect
- Against minimal physiotherapy, physiotherapy exercise improved function (SMD -0.37, 95% CI -0.62 to -0.12) and pain (SMD -0.45, 95% CI -0.85 to -0.06) at 3 to 4 months. Outpatient and home-based programs did not differ for function or pain, and adding balance or cycling made no difference [13].
- Population
- 1,739 patients with recent total knee replacement in 18 trials [13].
- Sources
- [13]
- Caveats
- Studies were small and underpowered individually and combined [13].
Muscle recovery after hard exercise
One trial of 36 combat athletes found drainage after jumping exercise raised pain thresholds and lowered creatine kinase and C-reactive protein more than passive rest.
Compared with passive rest [10]; intense sports massage [10]
The numbers and sources
- Effect
- Six 30-minute drainage sessions over 72 hours raised pressure pain thresholds more than passive rest at 24, 48 and 72 hours (p = 0.004 to < 0.001), with larger gains than sports massage at 24 hours. Creatine kinase and C-reactive protein were lower than with rest (p < 0.001 to 0.017). Sports massage increased muscle blood flow more [10].
- Population
- 36 combat sports athletes, 24 men and 12 women, mean age 27.4 [10].
- Sources
- [10]
- Caveats
- One small trial with no sham. Perceived recovery was measured, and the abstract does not report its result [10].
Strength, sprint and performance recovery
Mixed results: one meta-analysis found no effect on strength, jump, sprint or endurance, while others found small gains in force or short-term performance recovery.
Compared with no intervention [8]; control conditions the source abstracts do not describe [10][11]
The numbers and sources
- Effect
- Across 29 studies, massage did not improve strength, jump, sprint, endurance or fatigue [10]. In another pooled analysis, maximal isometric force (SMD 0.56) and peak torque (SMD 0.38) were higher after massage [8]. Across 22 trials, performance recovery effects were small: +6.6% with 5 to 12 minutes of massage and +1.0% with more than 12 minutes, larger for recovery periods of up to 10 minutes (+7.9%) than more than 20 minutes (+2.4%) [11].
- Population
- 1,012 participants in 29 studies [10]. 504 participants in 11 trials [8]. 22 randomized trials [11].
- Sources
- [10], [8], [11]
- Caveats
- The authors of [11] called the effects rather small and partly unclear, larger in untrained people than in trained athletes.
Recovery and flexibility in athletes
Limited evidence: small trials against mostly untreated controls reported less pain and more range of motion, and a sham-controlled study found no change in hamstring flexibility.
Compared with mostly untreated control groups [9]; sham cupping and no treatment [10]
The numbers and sources
- Effect
- Across 11 trials in athletes, cupping was reported to lower pain and disability, increase range of motion and reduce creatine kinase against mostly untreated controls [9]. In 25 adults with tight hamstrings, 10 minutes of cupping did not change flexibility compared with sham or control (p = 0.35 and 0.36) [10].
- Population
- 498 amateur and professional athletes in 11 trials [9]. 25 healthy adults in a crossover study [10].
- Sources
- [9], [10]
- Caveats
- Most athlete trials were at unclear or high risk of bias, and none reported safety [9].
Practices
Muscle soreness after exercise
Shown to reduce muscle soreness for up to 96 hours after exercise compared with rest, in pooled trials rated low in quality.
The numbers and sources
- Effect
- A Cochrane review of 17 trials (366 participants) found less soreness than passive rest at 24 hours (SMD -0.55, 95% CI -0.84 to -0.27), 48 hours (SMD -0.66, 95% CI -0.97 to -0.35), 72 hours (SMD -0.93, 95% CI -1.36 to -0.51) and 96 hours (SMD -0.58, 95% CI -1.00 to -0.16). Cold water did not differ from contrast or warm water immersion [1]. A meta-analysis of 9 RCTs described cold water immersion as slightly better than passive recovery for immediate and delayed soreness [2]. An update with 44 trials found it superior to control for delayed soreness in every subgroup except the longest immersions [3]. Across 52 studies, soreness was lower 24 hours after high-intensity exercise (SMD -0.89, 95% CI -1.48 to -0.29) and perceived recovery was higher (SMD 0.66, 95% CI 0.29 to 1.03) [4].
- Population
- 366 participants in 17 small trials [1]. Participants in 9 RCTs [2]. Athletes and non-athletes in 44 trials [3]. Physically active people in 52 studies [4].
- Sources
- [1], [2], [3], [4], [5]
- Caveats
- Soreness is self-rated and nobody can be blinded to cold water. Study quality was low and results were heterogeneous [1]. A 2026 umbrella review of 14 reviews found the same primary studies reused across reviews, so their agreement is not independent replication. It rated confidence low in 2 reviews and critically low in 12, and called the clinical importance of the soreness effect uncertain [5].
Muscle soreness after exercise
Shown to ease muscle soreness after exercise when applied within an hour, in pooled trials, with hot packs ranking highest in a network analysis.
Compared with control groups the abstract does not describe [10]; passive recovery and other cold and heat methods [11]
The numbers and sources
- Effect
- Heat lowered soreness within 24 hours (SMD -1.17, as reported with a 95% CI of -2.62 to -0.09) and after 24 hours (SMD -0.82, 95% CI -1.38 to -0.26). Hot packs lowered it within 24 hours (SMD -2.31) and after (SMD -1.78), while other heat methods did not differ from control. Heat and cold did not differ from each other (P = 0.16) [10]. In a network analysis of ten methods, hot packs ranked first for pain relief at 24 and 48 hours [11].
- Population
- 1,098 people in 32 trials [10]. 1,367 people in 59 trials [11].
- Sources
- [10], [11]
- Caveats
- Both reviews come from the same group and note limited trial quality [10][11].
Recovery after training
Small trials found less muscle soreness and a smaller drop in jump performance after a post-exercise infrared sauna, with no difference after a strength session in one study.
The numbers and sources
- Effect
- In 16 male basketball players, 20 minutes at 43°C after resistance exercise attenuated the drop in countermovement jump 14 hours later and lowered muscle soreness against passive rest (p < 0.01) [20]. In 10 active men, 30 minutes of far-infrared sauna after a strength session produced no difference in any recovery measure. After an endurance session, jump height at 30 minutes was 0.34 m with sauna and 0.32 m without (p < 0.05) [21]. In 40 female athletes, muscle soreness rose 36 hours after exercise only in the group without sauna [22].
- Population
- 16 male basketball players in a randomized crossover [20]. 10 physically active men [21]. 40 female team sport athletes, pair-matched into two groups [22].
- Sources
- [20], [21], [22]
- Caveats
- Small samples, and soreness is self-rated by people who know whether they used the sauna. Temperatures were mild, 35°C to 50°C.
Recovery of power and performance
Mixed results: pooled trials found small gains in next-day muscular power and no effect on strength recovery, and umbrella reviews call performance findings inconsistent.
The numbers and sources
- Effect
- Cold water immersion improved recovery of muscular power 24 hours after eccentric exercise (SMD 0.34, 95% CI 0.06 to 0.62) and high-intensity exercise (SMD 0.22, 95% CI 0.004 to 0.43), and lowered creatine kinase 24 hours after high-intensity exercise (SMD -0.85, 95% CI -1.61 to -0.08). Recovery of strength did not differ from passive recovery after either type of exercise [4]. An umbrella review of 15 meta-analyses reported better muscular power and jump performance at 24 to 48 hours despite impaired jumping in the first hours after immersion, and no improvement in strength performance [6]. A second umbrella review judged findings for objective performance inconsistent, time-dependent or comparator-dependent [5].
- Population
- Physically active people in 52 studies [4]. 161 unique studies across 15 meta-analyses [6]. 14 reviews [5].
- Sources
- [4], [6], [5]
- Caveats
- Certainty of evidence was rated low to very low, mainly for inconsistency and imprecision [6]. The lower confidence limit for power after high-intensity exercise sits at zero [4].
Muscle soreness and damage after exercise
Mixed results: one meta-analysis found no substantial effect on exercise-induced muscle pain or strength loss, and another in athletes found lower soreness and creatine kinase.
The numbers and sources
- Effect
- Across 15 studies (317 participants) of a single session before or after exercise, creatine kinase was lower only when laser was applied before exercise (SMD -0.66, 95% CI -1.30 to -0.02). Swelling, range of movement and strength did not differ from placebo, and the authors concluded phototherapy may not have a substantial effect on exercise-induced muscle injury and pain [20]. A meta-analysis in athletes reported a lower soreness index, creatine kinase and interleukin-6 with laser therapy [19].
- Population
- 317 participants in 15 placebo-controlled studies [20]. Athletes in 24 studies [19].
- Sources
- [20], [19]
- Caveats
- Substantial heterogeneity limited the pooled analyses [20]. The athlete review gives no effect sizes in its abstract [19].
Muscle soreness after exercise
Mixed results: a Cochrane review found insufficient evidence that whole-body cryotherapy reduces soreness, and two placebo-controlled trials found it no better than a sham treatment.
The numbers and sources
- Effect
- A Cochrane review of 4 trials (64 participants) found lower soreness at 1 hour (SMD -0.77, 95% CI -1.42 to -0.12). At 24 hours (SMD -0.57, 95% CI -1.48 to 0.33), 48 hours (SMD -0.58, 95% CI -1.37 to 0.21) and 72 hours (SMD -0.65, 95% CI -2.54 to 1.24) the intervals included no difference [2]. A review of 16 studies reported muscle pain was reduced in 80% of them [3]. After a marathon, 31 runners randomized to cryotherapy, cold water immersion or a placebo showed no advantage of either cold treatment over placebo for functional recovery or perceived training stress [4]. After a resistance session in 24 men, cryotherapy lowered soreness at 24 hours compared with cold water and placebo, and neither cold treatment sped recovery more than placebo overall [5].
- Population
- 64 physically active young adults, all but 4 of them men [2]. Healthy, physically active people in 16 studies [3]. 31 endurance-trained men [4]. 24 resistance-trained men [5].
- Sources
- [2], [3], [4], [5]
- Caveats
- Cochrane rated all evidence very low in quality, with a high risk of bias in every trial, and concluded there was insufficient evidence [2]. The 16-study review counted positive studies and did not pool them [3]. The placebo-controlled trials suggest belief in the treatment may account for part of the reported benefit [4].
Muscle damage and soreness after exercise
One sham-controlled trial of 32 young men found creatine kinase did not rise after damaging exercise with grounding, while it rose with sham. Pain occurred in both groups.
Compared with sham grounding, with the same equipment not connected to the earth [4][5]
The numbers and sources
- Effect
- After 200 half-knee bends, men grounded for 4 hours on days 1 and 2 had no significant rise in creatine kinase on day 2, while the sham group did (P < 0.01). The between-group difference was significant (P = 0.04). Both groups had pain on every day after exercise [4]. In an 8-person pilot, pain scores and creatine kinase were among the measures that differed by 10% or more between grounded and sham groups [5].
- Population
- 32 healthy young men, 16 grounded and 16 sham [4]. 8 healthy adults, 4 per group [5].
- Sources
- [4], [5]
- Caveats
- The trial was funded by Earth FX Inc., which also supplied the products, and both authors named in its disclosure worked as contractors for Earth FX. The authors state the funder had no role in the study [4]. The pilot set its own 10% threshold rather than testing significance [5].
Recovery after hard training
Mixed results: swimmers were slower the morning after a post-training sauna, while a sauna before eccentric exercise reduced strength and motion losses in one small trial.
The numbers and sources
- Effect
- In 20 competitive swimmers and triathletes, a 4 x 50 m all-out swim the next morning was 1.69 s slower after 3 x 8 minutes of sauna at 80°C to 85°C, against 0.66 s faster after a placebo treatment (P = .02). Perceived stress was higher after sauna [25]. In 28 young adults, a sauna before eccentric wrist exercise led to smaller deficits in range of motion, grip strength and wrist extension strength than no sauna (P < 0.05) [26].
- Population
- 20 swimmers and triathletes in a randomized crossover [25]. 28 adults with a mean age of 20.9, randomized to sauna or control [26].
- Sources
- [25], [26]
- Caveats
- Two small trials asking different questions, one of sauna after training and one of sauna before it. The authors of [25] put the smallest meaningful change in this swim test at 1.2 s.
Recovery of muscle function
Mixed results: a review counted better performance recovery in most studies, while a marathon trial found worse muscle function after cryotherapy than after cold water immersion.
The numbers and sources
- Effect
- In a review of 16 studies, measures of athletic capacity and performance improved in 71% of studies using controlled exercise [3]. After a marathon, cryotherapy had a harmful effect on muscle function compared with cold water immersion and was no better than placebo [4]. After resistance exercise, peak force at 48 hours was higher with cryotherapy than with cold water or placebo, and most other outcomes were trivial, unclear or favored placebo [5]. In 14 academy soccer players, peak power, soreness and perceived recovery did not differ from seated rest after one session [6].
- Population
- Physically active people in 16 studies [3]. 31 male marathon runners [4]. 24 resistance-trained men [5]. 14 professional academy soccer players in a crossover [6].
- Sources
- [3], [4], [5], [6]
- Caveats
- Small trials with different temperatures, timings and exercise models. Only the two Wilson trials used a placebo.
Exercise performance and recovery
Not shown to improve exercise performance or recovery when given before or after exercise. A Cochrane review found more muscle soreness at 48 hours with immediate treatment.
The numbers and sources
- Effect
- In a meta-analysis of physically active adults, hyperbaric oxygen before exercise had no significant effect on performance and after exercise had no significant effect on recovery (10 studies reviewed, 6 pooled with 69 participants) [22]. A Cochrane review of 9 trials (219 participants) found higher pain at 48 hours in people given hyperbaric oxygen straight after muscle-damaging exercise (mean difference 0.88 on a 0 to 10 scale, 95% CI 0.09 to 1.67), with no difference in swelling or strength. Two trials in ankle sprain and knee ligament injury found no difference from sham [23].
- Population
- 166 physically active adults in 10 studies [22]. 219 participants in 9 small trials [23].
- Sources
- [22], [23]
- Caveats
- Small trials. Individual studies of oxygen breathed during exercise reported better muscle endurance, which could not be pooled [22].
Devices and wearables
Resting heart rate variability with training guided by daily readings
Shown to raise resting heart rate variability more than a fixed training plan in one meta-analysis, with no difference in resting heart rate.
The numbers and sources
- Effect
- Training guided by heart rate variability raised vagal-related heart rate variability indices more than predefined training (SMD 0.50, 95% CI 0.09 to 0.91). Resting heart rate did not differ (SMD 0.04, 95% CI -0.34 to 0.43) [23].
- Population
- Adults in endurance training trials [23].
- Sources
- [23]
- Caveats
- The outcome is the same measure used to steer the training. The authors note that index choice, recording position and baseline methods differed between trials [23].