Kaminski 1992.

Methods	Randomised controlled trial (cross‐over design)
Participants	Setting: laboratory; USA n = 25 healthy college students and college employees. Of the 25 original participants, 2 dropped out of the experiment, 3 were excluded for a variety of reasons (loss of capsule integrity, failure to properly maintain records, non‐compliance with the experimental protocol), and 1 was removed for failure to develop delayed onset muscle soreness in either trial. Left with 19 participants (6 women and 13 men). Age rage 24 to 48 years Inclusion/exclusion criteria Participants were excluded from the study if they were older than 50 years, had a sensitivity to lactose, took analgesic or anti‐inflammatory agents during the trials, participated in rigorous athletic training, had a current musculoskeletal ailment in the legs, or took ascorbic acid or riboflavin supplements within 3 weeks of the study
Interventions	Intervention Vitamin C 1000 mg as 3 capsules per day Placebo Lactose capsules Duration Vitamin C taken 3 days before and 7 days after exercise with a 3‐week washout period
Outcomes	PRIMARY Delayed onset muscle soreness was monitored by self‐reporting using a 10 cm continuous unmarked line as a visual analogue scale anchored with 1 "have no soreness" at one end and 10 "my soreness could not be any worse" at the other
Exercise type	Strenuous eccentric work of the plantar flexors of the calf
Sources of funding	None
Notes	Participants were asked to refrain from using anti‐inflammatory medication and other supplements for the duration of the study Authors were contacted to request raw data for delayed onset muscle soreness on 3 December 2013 and responded on 9 December 2013
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomised using a computer program
Allocation concealment (selection bias)	Unclear risk	No details provided in manuscript Authors were contacted via email on 14 May 2016 with no response
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Double‐blind
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Double‐blind
Incomplete outcome data (attrition bias) All outcomes	High risk	6 participants dropped out and were excluded for a variety of reasons Attrition rate: 24%
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	Low risk	Participants were asked to refrain from using anti‐inflammatory medication and other supplements for the duration of the study