Exercise induced muscle damage (EIMD) causes reductions in neuromuscular function and
muscle soreness with inter- and intra-individual variability. New Zealand blackcurrant (NZBC)
is rich in polyphenols, namely anthocyanins, which improve blood flow and display anti-inflammatory properties that may improve recovery from EIMD. Therefore, the aim of this
thesis is to examine whether NZBC extract supplementation improves recovery from EIMD.
Study 1 showed that seven-days of NZBC extract supplementation had no effect on recovery
from EIMD (Counter Movement Jump (CMJ), soreness, urinary interleukin-6 (IL-6)) in the 48
h following a half-marathon running race. Study 2 investigated the inter-individual variability in
EIMD following the half-marathon and showed that by quantifying the Smallest Worthwhile
Change (SWC), individuals within the NZBC group appeared to recover some CMJ variables
quicker than placebo and the Į-actinin-3 (ACTN3) and angiotensin-I converting enzyme (ACE)
genotypes may partially explain recovery of muscle function. Study 3 showed that seven-days
NZBC extract supplementation had no effect on EIMD following a 100-drop jump protocol
(100-DJP) on markers of muscle function (CMJ and voluntary and electrically stimulated
isometric contractions), muscle soreness and serum IL-6 and prostaglandin-E2. Study 4
showed that following the 100-DJP, on the individual level (using the SWC), NZBC extract
supplementation had no effect on recovery of muscle function but the ACTN3 and TTN
genotypes may influence recovery of muscle function. Study 5 quantified the time course and
appearance of the phenolic acids vanillic acid (VA), gallic acid (GA) and protocatechuic acid
(PCA) following a single dose of NZBC supplementation and it was observed that VA, GA and
PCA were most abundant at 3, 4 and 1.5 h post-ingestion, respectively. Study 6 showed that
seven-days of NZBC extract supplementation prior to a 100-DJP and three-days after (10
days total) increased plasma concentrations of PCA and GA but not VA, and there were no
relationships with changes the EIMD. In summary, the research presented in this thesis shows
that NZBC extract supplementation has no effect on recovery following EIMD on the group
level but may be effective at an individual level. Acute and chronic supplementation of NZBC
extract increased plasma concentrations of key phenolic acids, which shows inter-individual
variation but is not related to recovery from EIMD. Future research should investigate the
appearance of a wider range of phenolic acids alongside exercise performance measures to
help inform personalised use of pol\phenol supplements to enhance individual's performance.