No Effect of New Zealand Blackcurrant Extract on Recovery of Muscle Damage Following Running a Half-Marathon

New Zealand blackcurrant (NZBC) contains anthocyanins, known to moderate blood flow and display anti-inflammatory properties that may improve recovery from exercise-induced muscle damage (EIMD). We examined whether NZBC extract supplementation enhances recovery from EIMD after a half-marathon race. Following a randomized, double-blind, independent groups design, 20 (8 women) recreational runners (age 30 ± 6 years, height 1.73 ± 0.74 m, body mass 68.5 ± 7.8 kg, half-marathon finishing time 1:56:33 ± 0:18:08 h:min:s) ingested either two 300 mg·day-1 capsules of NZBC extract (CurraNZ™) or a visually matched placebo (PLA), for 7-days prior to and 2-days following a half-marathon. Countermovement jump (CMJ) performance variables, urine interleukin-6 (IL-6), perceived muscle soreness and fatigue were measured pre-, post-, and at 24 h and 48 h after the half-marathon and analysed using a mixed linear model with statistical significance set a priori at P<0.05. The CMJ performance variables were reduced immediately post-half-marathon (P<0.05) with all returning to pre half-marathon by 48 h levels except concentric and eccentric peak force and eccentric duration, with no difference in response between groups (P>0.05). Urine IL-6 increased 48 h post-half-marathon in the NZBC group only (P<0.01) and remained unchanged compared to pre half-marathon levels in PLA group (P>0.05). Perceived muscle soreness and fatigue increased immediately post-half-marathon (P<0.01) and returned to pre half-marathon by 48 h, with no difference between groups (P>0.05). Supplementation with NZBC extract had no effect on the recovery of countermovement jump variables and perceptions of muscle soreness or fatigue following a half-marathon in recreational runners.