McCormick 2016.

Methods	Randomised, double‐blind (cross‐over design) 5‐week washout period
Participants	Setting: field/laboratory; Australia n = 9 highly‐trained (elite) male water polo players from the Western Australian Institute of Sport Mean age 18.6 (SD 1.4) Inclusion/exclusion criteria Not specified ‐ authors contacted on 4 February 2017 and a reply received 8 February 2017: "Participants had to be a part of the West Australian Institute of Sport Men’s High Performance Water polo squad that attend daily training sessions. Participants were not taking any vitamin supplements (as per WAIS supplements policy). Maintained daily contact with the research group to ensure consumption of the prescribed supplement."
Interventions	Intervention 90 mL daily for 6 days of tart Montmorency Cherry Juice (Prunus cerasus) concentrate (Cherry Active, Sunbury, UK) diluted with water, such that each 30 mL serving was made up into a 200 mL beverage. Both the cherry juice and placebo were consumed in 2 doses each day; 200 mL before morning training, and 400 mL in the evening post training. Placebo 3 different 'off the shelf' cordials: lime (Woolworths select lime cordial, Australia), cranberry (Bickford's cranberry juice cordial, Australia) and raspberry (Cottee's raspberry flavoured cordial, Australia). Cordials were mixed with food colouring and 480 mL of water in order to closely imitate the taste, colour and carbohydrate content. Duration 6 days
Outcomes	Primary Delayed onset muscle soreness (delayed onset muscle soreness) was measured on a 0 to 10 scale in the upper body, upper legs, lower legs and overall body encompassing the anchor points of 0 (normal; without pain or stiffness) to 10 (very painful) Total quality of recovery was also recorded on a 6‐ to 20‐point scale for the upper body, upper legs, lower legs and overall body, which encompassed the anchor points 6 (very, very poor recovery) to 20 (very, very good recovery) Secondary Swimming‐based tests comprised of the in‐water vertical jump test, 10 m sprint test, a repeat sprint test and the Water Polo Intermittent Shuttle Test
Exercise type	A fixed training regimen for 6 days. All training (technical skill, weights, and swimming) performed during the 7‐day trials was identical, and took place in the controlled environment of the indoor Water Polo pool or gymnasium.
Sources of funding	Manuscript states: "Funds received from the Australian Institute of Sport and the Australian Sports Commission"
Notes	This study was only included in the qualitative analysis because the exercise paradigm was completely different to all the other studies included in this review. The other studies used an exercise paradigm where mechanical or whole body aerobic exercise was used to cause muscle damage and then a range of outcomes such as muscle soreness, muscle function, range of motion and performance were measured at various time points up to several days after exercise. However, participants in this study had a fixed daily training regimen for 5 continuous days performance, with outcomes being measured at the start and then throughout the trial. Thus the severity of muscle damage caused by the daily training regimen was not controlled
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Manuscript states: "randomised, double‐blind, repeated measures, crossover design". No specific details provided on how randomisation was completed Authors contacted on 4 February 2017 and response was received on 8 February 2017: "Each participant was assigned a participant number and randomised by a number generator into two separate groups."
Allocation concealment (selection bias)	Low risk	No specific details provided on how randomisation was completed Authors contacted on 4 February 2017 and a response was received on 8 February 2017: "Fluids were prepared (by an independent researcher) in the absence of the athletes and researchers involved in the performance testing. PLA was made to look and taste the same as the CJ (specific product details within the manuscript). Bottles were then labelled with athlete names to ensure no mix‐up."
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Manuscript states: "randomised, double‐blind, repeated measures, crossover design"
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Double‐blind
Incomplete outcome data (attrition bias) All outcomes	Low risk	No details in the manuscript Authors contacted on 4 February 2017 and a response was received on 8 February 2017: "Initial sample size was n=11 however, two participants withdrew during the study due to injury. These participants were not included in the manuscript, leaving us with n=9."
Selective reporting (reporting bias)	High risk	No published protocol available All outcomes reported at all time points Adverse effects of antioxidant supplementation were not reported
Other bias	Unclear risk	Manuscript states: "A limitation of this investigation is that the anthocyanin concentration of both the commercial and placebo supplement used was not confirmed"