The effects of daily blackcurrant consumption for 6 weeks on cognitive performance before and after exercise-induced physical fatigue.

Inclusion criteria: Healthy individuals (male or female) 16‐50 years, who have not taken part in any formal fitness training in the last 4 months and are able to complete the physical fitness requirements of the study will be selected. They will need to be able to complete (i) health (ii) fitness (Baecke) questionnaires and (iii) perform with Wingate cycle test to the standard required. In addition, all participants will provide written consent for this study. Exclusion criteria: Participants will be excluded if they are unable or willing to provide informed written consent or comply with the study procedures. Participants will also be excluded if they have (i) known hypersensitivity or intolerance to blackcurrants or berry fruit and/or berryfruit derived products (ii) have health conditions that impair ability to perform Wingate cycle exercise (e.g. injury, hernia, back or joint pain, cardiovascular and breathing problems or fail to demonstrate a certain fitness level, assessed by a Baecke questionnaire, or are unable to perform the Wingate cycle exercise to the standard required by the trial co‐ordinator, and (iii) health conditions that may affect ability to do computerized cognitive tasks (e.g. eye sight problems, colour blindness, aura migraines, epilepsy). In addition, participants will be excluded if they are pregnant or planning to get pregnant in the near future or have any of the following conditions; (i) blood borne diseases (e.g. hepatitis), (ii) clinically diagnosed high/low blood pressure, (iii) recent bacterial or viral illness, (iv) are taking any medication that affects the properties of blood (e.g. blood clotting). This is a two‐arm, double blind intervention feeding trial that will involve volunteers (16‐50yrs). We aim to recruit 50 participants who will be split into two groups. In group one the participants will receive blackcurrant extract (240mg anthocyanins via oral capsule, everyday for 6 weeks) and participate in fatiguing/cognitive performance (week 1 and week 7). In group two the participants will receive a matched sugar placebo (240mg fructose and glucose via oral capsule, everyday for 6 weeks) and participate in fatiguing/cognitive performance (week 1 and week 7). The fatiguing sessions is a cycle test for 30 secs intervals. The fatigue threshold is calculated as the intensity where the individual displays a decline in peak cycle power output and a blood lactate level above their lactate threshold. this will vary between participants depending on their fitness level. Participants will complete the 30 secs cycle with 1 minute rest intervals until they are tired. They will complete this cycle test at the beginning of week one twice (once for baseline and to establish fatigue threshold) and then twice at the end of week seven. These sessions will be administrated by a physiotherapist and a qualified first aider will also be present. The cognitive performance will take 15 ‐ 20 minutes (twice at both weeks 1 and 7) and consists of computerized tests. Over the 6 week feeding period the participants will be asked to consume their supplements (blackcurrant or placebo) in the morning at the same time. At the beginning of the week they will be asked to complete an online diet, energy, health and mood (PoMs) questionnaire. This questionnaire will ask them about their adherence to the pill schedule. Furthermore, participants will collect their pills once a week from the trial coordinator, who will also discuss adherence with the participants at that time. Randomization will be performed using a randomization schedule designed by a biostatistician, with study investigators and subjects blind to group allocation. Cognitive performance;Physical exercise performance Leukocyte mitochondrial DNA fragility