Does Combined Antioxidant Vitamin Supplementation Blunt Repeated Bout Effect?

Abstract

We investigated the effect of antioxidant supplementation on markers of muscle damage, antioxidant status, and delayed onset of muscle soreness (DOMS) after repeated downhill runs. Moderately-trained males (n=22) were randomly assigned to a supplement (S) or placebo (P) group. Capsules (vitamin C:1?000?mg/d; vitamin E: 400 IU/d) were ingested daily for 2 weeks. before the first (1D) and second (2D) downhill runs, and for 2 additional days following each run. Creatine kinase (CK) activity and oxygen radical absorbance capacity (ORAC) were measured pre-exercise and at 0 (immediately), 6, 24 and 48?h post-exercise (POST). DOMS was rated for quadriceps, hamstring, gluteus, gastrocnemius, and tibialis anterior at 0, 24, 48 and 72?h POST. CK at 48?h following 1D remained elevated above pre-exercise only in P (P<0.01). Overall, DOMS of the quadriceps was lower in S (1.1?0.3) than P (2.2?0.5) (P<0.05). At 24?h POST in S, CK was lower (P<0.01) and ORAC was higher (P<0.05) following 2D than 1D. CK and ORAC following 2D were blunted and augmented, respectively, in response to 1D and antioxidant supplementation enhanced this protective effect as indicated by an attenuation of biomarkers of muscle damage and a greater antioxidant capacity observed 24?h POST 2D.

Antioxidant-rich beetroot juice does not adversely affect acute neuromuscular adaptation following eccentric exercise

“…Furthermore, studies examining the effects of antioxidants on adaptation to a single bout of eccentrically biased exercise, where muscle damage is principally induced via mechanical stress, are scarce. Nevertheless, our findings are in agreement with those of a recent study, in which 2 weeks of vitamin C and E supplementation did not have any adverse effects on adaptation to repeated bouts of downhill running (He et al, 2015).…”

“…However, the fact that the adaptive response from a just single bout of eccentric exercise results from (at least in part) cellular changes, it would be anticipated that antioxidant supplementation might attenuate the magnitude of the RBE. To date, this possibility has only been addressed by one recent study, which showed that 2 weeks of supplementation with a high antioxidant dose of vitamin C (1000 mg•d•¯1) and E (400 I•U¯1) did not blunt the RBE in response to a bout of downhill running (He, Hockemeyer and Sedlock, 2015). This was evidenced by the similar attenuations in muscle soreness and plasma creatine kinase (CK) in bout 2 compared to bout 1 for both the supplementation and placebo group.…”

Redox Mechanism of Reactive Oxygen Species in Exercise

“…Antioxidant vitamins have demonstrated potential prophylactic effects. In the study performed by He et al, short-term combined vitamin C and E supplementation not only attenuated levels of creatine kinase (a muscle damage marker) and muscle soreness, but also enhanced muscle protection following the second bout of aerobic exercise (He et al, 2015). Moreover, a supplemental or adequate intake of nutritional antioxidants is necessary for endurance athletes (Wagner et al, 2010).…”

Antioxidants for preventing and reducing muscle soreness after exercise: a Cochrane systematic review

“…All 50 studies were randomised controlled trials; no quasirandomised controlled trials met the inclusion criteria. Thirty-eight trials (with a total of 901 participants) employed a parallel design 21 22 27–60. The other 12 trials (with a total of 188 participants) employed a crossover design 61–72…”

“…In all trials, an antioxidant supplement was compared with a placebo. Thirteen trials used antioxidants from a whole natural food source,22 29 30 41 44 46 51 62 64 65 68 71 72 19 used an antioxidant extract or mixed antioxidants27 32 35 37 38 40 42 43 45 48 49 52 53 55 61 66 67 69 and 18 provided either vitamin C or vitamin E or both together 21 28 31 33 34 36 39 47 50 54 56 58–60 63 70 73 74. All studies used a placebo either as a powder, capsule or drink; however, three studies did not provide details of what the placebo comprised 47 50 61.…”