***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: There is no consensus regarding the effects of mixed antioxidant vitamin C and /or vitamin E supplementation on oxidative stress responses to exercise and restoration of muscle function . Thirty-eight men were r and omly assigned to receive either placebo group ( n = 18 ) or mixed antioxidant ( primarily vitamin C & E ) supplements ( n = 20 ) in a double-blind manner . After 6 weeks , participants performed 90 min of intermittent shuttle-running .  Peak isometric torque of the knee flexors/extensors and range of motion at this joint were determined before and after exercise , with recovery of these variables tracked for up to 168 h post-exercise . Antioxidant supplementation elevated pre-exercise plasma vitamin C ( 93 ± 8 μmol l−1 ) and vitamin E ( 11 ± 3 μmol l−1 ) concentrations relative to baseline ( P < 0.001 ) and the placebo group ( P ≤ 0.02 ) . Exercise reduced peak isometric torque ( i.e. 9–19 % relative to baseline ; P ≤ 0.001 ) , which persisted for the first 48 h of recovery with no difference between treatment groups . In contrast , changes in the urine concentration of F2-isoprostanes responded differently to each treatment ( P = 0.04 ) , with a tendency for higher concentrations after 48 h of recovery in the supplemented group ( 6.2 ± 6.1 vs. 3.7 ± 3.4 ng ml−1 ) . Vitamin C & E supplementation also affected serum cortisol concentrations , with an attenuated increase from baseline to the peak values reached after 1 h of recovery compared with the placebo group ( P = 0.02 ) and serum interleukin-6 concentrations were higher after 1 h of recovery in the antioxidant group ( 11.3 ± 3.4 pg ml−1 ) than the placebo group ( 6.2 ± 3.8 pg ml−1 ; P = 0.05 ) . Combined vitamin C & E supplementation neither reduced markers of oxidative stress or inflammation nor did it facilitate recovery of muscle function after exercise-induced muscle damage ABSTRACT This investigation determined the efficacy of black currant nectar ( BCN ) in reducing symptoms of exercise-induced muscle damage ( EIMD ) . Sixteen college students were r and omly assigned to drink either 16 oz of BCN or a placebo ( PLA ) twice a day for eight consecutive days . A bout of eccentric knee extensions ( 3 × 10 sets @ 115 % of 1RM ) was performed on the fourth day . Outcome measures included muscle soreness ( subjective scale from 0 to 10 ) and blood markers of muscle damage ( creatine kinase , CK ) , inflammation ( interleukin-6 , IL-6 ) , and oxygen radical absorbance capacity ( ORAC ) . Although there were no differences in reported soreness between groups , consumption of BCN  reduced CK levels at both 48 ( PLA = 82.13 % vs. BCN = −6.71 % , p = .042 ) and 96 h post exercise ( PLA = 74.96 % vs. BCN = −12.11 % , p = .030 ) . The change in IL-6 was higher in the PLA group ( PLA = 8.84 % vs. BCN = −6.54 % , p = .023 ) at 24 h post exercise . The change in ORAC levels was higher in the treatment group ( BCN = 2.68 % vs. PLA = −6.02 % , p = .039 ) at 48 h post exercise . Our results demonstrate that consumption of BCN prior to and after a bout of eccentric exercise attenuates muscle damage and inflammation Purpose Polyphenolic curcumin is known to have potent anti-inflammatory effects ; thus the present study investigated the hypothesis that curcumin ingestion would attenuate muscle damage after eccentric exercise . Methods Fourteen untrained young men ( 24 ± 1 years ) performed 50 maximal isokinetic ( 120 ° /s ) eccentric contractions of the elbow flexors of one arm on an isokinetic dynamometer and the same exercise with the other arm 4 weeks later . They took 150 mg of curcumin ( theracurmin ) or placebo ( starch ) orally before and 12 h after each eccentric exercise bout in a r and omised , crossover design . Maximal voluntary contraction ( MVC ) torque of the elbow flexors , range of motion of the elbow joint , upper-arm circumference , muscle soreness , serum creatine kinase ( CK ) activity , and plasma interleukin-6 ( IL-6 ) and tumor necrosis factor-α ( TNF-α ) concentration were measured before , immediately after , and 24 , 48 , 72 and 96 h after each eccentric exercise . Changes in these variables over time were compared between curcumin and placebo conditions by two-way repeated measures ANOVA . Results MVC torque decreased smaller and recovered faster ( e.g. , 4 days post-exercise : −31 ± 13 % vs. −15 ± 15 % ) , and peak serum CK activity was smaller ( peak : 7684 ± 8959 IU/L vs. 3398 ± 3562 IU/L ) for curcumin than placebo condition ( P < 0.05 ) . However , no significant differences between conditions were evident for other variables , and no significant changes in IL-6 and TNF-α were evident after exercise . Conclusion It is concluded that theracurmin ingestion attenuates some aspects of muscle damage such as MVC loss and CK activity increase The aim of this study was to investigate whether post-exercise vitamin C supplementation influences recovery from an unaccustomed bout of exercise . Sixteen male subjects were allocated to either a placebo ( P ; n=8 ) or vitamin C ( VC ) group ( n=8 ) . Subjects performed a prolonged ( 90-min ) intermittent shuttle-running test , and supplementation began after the cessation of exercise . Immediately after exercise the VC group consumed 200 mg of VC dissolved in a 500 ml drink , whereas the subjects in the P group consumed the drink alone . Later on the same day and then in the morning and evening of the following 2 days , subjects consumed additional identical drinks . Plasma VC concentrations in the VC group increased above those in the P group 1 h after exercise and remained above P values for the 3 days after exercise . Nevertheless , post-exercise VC supplementation was not associated with improved recovery . Post-exercise serum creatine kinase activities and myoglobin concentrations were unaffected by supplementation . Muscle soreness and the recovery of muscle function in the leg flexors and extensors were not different in VC and P groups . Furthermore , although plasma concentrations of interleukin-6 and malondialdehyde increased following exercise , there was no difference between VC and P groups . These results suggest that either free radicals are not involved in delaying the recovery process following a bout of unaccustomed exercise , or that the consumption of VC wholly after exercise is unable to deliver this antioxidant to the appropriate sites with sufficient expediency to improve recovery PURPOSE Dietary supplementation with polyphenols , particularly ellagitannins , may attenuate the muscular damage experienced after eccentric exercise , producing delayed-onset muscle soreness . The purpose of this study was to determine whether ellagitannin supplementation from Wonderful variety pomegranate extract ( POMx ) improved recovery of skeletal muscle strength after eccentric exercise . METHODS Recreationally active males were r and omized into a crossover design with either pomegranate extract ( POMx ) or placebo ( PLA ) , each given during a period of 9 d . To produce delayed-onset muscle soreness , subjects performed two sets of 20 maximal eccentric elbow flexion exercises with one arm . Maximal isometric elbow flexion strength and muscle soreness as well as serum measures of creatine kinase , myoglobin , interleukin 6 , and C-reactive protein were made at baseline and 2 , 24 , 48 , 72 , and 96 h after exercise . RESULTS With both treatments , strength was similarly reduced 2 h after exercise ( i.e. , 72 % of baseline ) , and recovery of strength was incomplete after 96 h ( i.e. , 91 % of baseline).However , strength was significantly higher in POMx compared with that in PLA at 48 h ( 85.4 % + /- 2.5 % and 78.3 % + /- 2.6 % , P = 0.01 ) and 72 h ( 88.9 % + /- 2.0 % and 84.0 % + /- 2.0 % , P = 0.009 ) after exercise . Serum markers of inflammation and muscle damage did not provide insight regarding possible mechanisms . CONCLUSIONS Supplementation with ellagitannins from pomegranate extract significantly improves recovery of isometric strength 2 - 3 d after a damaging eccentric exercise The objective of the study was to verify the effect of N-acetylcysteine ( NAC ) supplementation on parameters of oxidative damage and inflammatory response after high-intensity eccentric exercise ( EE ) .  29 participants with a mean age of 21.3+/-4 yr , weight of 74.5+/-7.7 kg , and height of 177.2+/-6.9 cm were selected and divided r and omly into 3 groups : placebo ( 21 days ; n=8 ) , NAC ( 21 days ; n=9 ) , and NAC plus placebo ( 14 days ; n=8 ) . Four participants withdrew from the study for personal reasons . 14 days after starting supplementation , the participants performed EE : 3 sets until exhaustion ( elbow flexion and extension on the Scott bench , 80 % 1RM ) . Blood sample s were collected before and on the 2nd , 4th , and 7th day after EE .  Muscle soreness ( MS ) , lipoperoxidation , protein carbonylation , tumor-necrosis factor- ( TNF- ) , and interleukin 10 ( IL-10 ) were determined . Results showed a significant increase in MS in all the groups on the 2nd day after EE and a decrease in the following days . A significant increase was observed in malondialdehyde and carbonyl levels on the 4th and 7th days after EE in all groups . TNF- increased significantly on the 2nd day after eccentric exercise and decreased in the following days irrespective of NAC supplementation ; concentration of IL-10 increased significantly on the 4th day in all groups . Only the supplemented groups maintained high levels of IL-10 on the 7th day after EE . The results suggest that treatment with NAC represents an important factor in the defense against muscle soreness and has different effects on oxidative damage and pro- and anti-inflammatory cytokines Background Delayed onset muscle soreness ( DOMS ) due to eccentric muscle activity is associated with inflammatory responses and production of reactive oxygen species ( ROS ) that sustain both inflammation and oxidative stress . Curcumin , a powerful promoter of anti-oxidant response , is one of the best-investigated natural products , and is now commercially available as a lecithin delivery system ( Meriva ® , Indena SpA , Milan ) with improved bio-availability . The aim of this study was to test whether curcumin could attenuate damage from oxidative stress and inflammation related to acute muscle injury induced by eccentric continuous exercise Methods This was a r and omised , placebo-controlled , single-blind pilot trial . Twenty male healthy , moderately active volunteers were r and omised to curcumin given as the Phytosome ® delivery system 1 g twice daily ( 200 mg curcumin b.i.d . ) or matching placebo . Supplementation was initiated 48 hours prior to a downhill running test and was continued for 24 hours after the test ( 4 days in total ) . Muscle damage was quantified by magnetic resonance imaging , laboratory tests and histological analyses on muscle sample s obtained 48 hours after the test . Patient-reported pain intensity was also recorded . Results Subjects in the curcumin group reported less pain in the lower limb as compared with subjects in the placebo group , although significant differences were observed only for the right and left anterior thighs . Significantly fewer subjects in the curcumin group had MRI evidence of muscle injury in the posterior or medial compartment of both thighs . Increases in markers of muscle damage and inflammation tended to be lower in the curcumin group , but significant differences were only observed for interleukin-8 at 2 h after exercise . No differences in markers of oxidative stress and muscle histology were observed Conclusions Curcumin has the potential for preventing DOMS , as suggested by its effects on pain intensity and muscle injury . Larger studies are needed to confirm these results and further clarify the mechanism of action of curcumin Background Both acute bouts of prior exercise ( preconditioning ) and antioxidant nutrients have been used in an attempt to attenuate muscle injury or oxidative stress in response to  resistance  exercise  .  However , most studies have focused on untrained participants rather than on athletes . The purpose of this work was to determine the independent and combined effects of antioxidant supplementation ( vitamin C + mixed tocopherols/tocotrienols ) and prior eccentric exercise in attenuating markers of skeletal muscle injury and oxidative stress in resistance trained men . Methods Thirty-six men were r and omly assigned to : no prior exercise + placebo ; no prior exercise + antioxidant ; prior exercise + placebo ; prior exercise + antioxidant . Markers of muscle/cell injury ( muscle 
    Output:
    
Thus , the effect sizes suggesting less muscle soreness  with antioxidant supplementation were very unlikely to equate to meaningful or important differences in practice .
There is moderate to low- quality evidence that high-dose antioxidant supplementation does not result in a clinical ly relevant reduction of muscle soreness after exercise of up to 6 hours or at 24 , 48 , 72 and 96 hours after exercise .
There is no evidence available on subjective recovery and only limited evidence on the adverse effects of taking antioxidant supplements