Shafat 2004.

Methods	Randomised controlled trial (parallel design)
Participants	Setting: laboratory; Ireland n = 12 moderately fit, active, non‐smoking men Mean age vitamin C group 25 (SD 7.5) years Mean age placebo group 20.6 (SD 1.1) years Inclusion/exclusion criteria All volunteers were moderately active non‐smokers who had not participated in any form of resistance training exercise in the previous 6 months. Volunteers who were currently taking supplements in the past 6 months were excluded from the study.
Interventions	Intervention 500 mg vitamin C and 1200 IU vitamin E; 2 x 250 mg tablets of vitamin C + 3 tablets 400 IU each vitamin E Placebo Glucose Duration 37 days
Outcomes	PRIMARY Delayed onset muscle soreness was evaluated using a questionnaire employing a visual analogue scale for a total of 8 sites (6 sites on the anterior muscle of the upper leg and 2 sites on the posterior muscles of the upper leg). The participants were asked to palpate the relaxed muscle and rate soreness on a scale of 1 "normal" to 10 "very very sore". Results were summed for the 8 sites so that no soreness is indicated by a score of 8 and maximal muscle soreness by a score of 80. SECONDARY Maximal voluntary concentric torque for the knee extensors was measured at an angular velocity of 0.5 rad/s 3 minutes to and 3 minutes following the eccentric contraction bout on the Con‐Trex dynamometer. Isometric maximum voluntary contraction force (MVC) and electrically simulated force of the knee extensors were measured using a custom made isometric test rig. Volunteers were seated in the upright position with their leg connected to a pre‐calibrated load cell (Novatech, Hastings, UK). Analogue signals from the strain gauge were converted to digital information using an A:D convertor (Powerlab 1400, ADInstruments, Oxfordshire, UK) and were recorded on a PC. The chair was adjusted to allow attachment of the strain gauge above the ankle with the knee at an angle of 1.57 rad (90 degrees). For MVC, volunteers were instructed to contract maximally for 3 seconds and verbally encouraged during their effort. 3 repetitions were performed, separated by 1 minute. The highest peak force value of the 3 repetitions was recorded as the MVC.
Exercise type	30 sets of 10 eccentric knee extensions at a velocity of 0.52 rad·s‐1
Sources of funding	None
Notes	—
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	No details in manuscript Authors were contacted via email on 26 May 2016 and responded on 5 June 2016: "Numbers were drawn out of a hat to determine a set allocation order which was balanced in numbers for treatment and placebo. As participants were recruited to the study, they were allocated to a group according to that random allocation order."
Allocation concealment (selection bias)	Unclear risk	No details in manuscript Authors were contacted via email on 26 May 2016 and responded on 5 June 2016: "All volunteers were informed that they were being supplemented. All were supplied with identical labelled dispensers, containing capsules. However, the capsules were not identical in colour or size. We checked, informally, at the end of the testing to see if volunteers thought they were supplemented or controlled and they really had no idea which was which"
Blinding of participants and personnel (performance bias) All outcomes	High risk	Non‐identical capsules; the personnel were not blinded
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Non‐identical capsules; some risk of unblinding
Incomplete outcome data (attrition bias) All outcomes	Low risk	All participants completed the study
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	Participants that took supplements or smoked were excluded No details on whether participants were asked to refrain from using anti‐inflammatory drugs or other treatment modalities that could reduce soreness