Staples 1999b.

Methods	Randomised, participant and probably assessor blind. Intention‐to‐treat analysis and no exclusions.
Participants	30 healthy male volunteers. Underwent deliberately provocative exercise of non‐dominant quadriceps muscle.
Interventions	Phase 2 (see Notes) HBOT (2 groups) (1) 100% oxygen at 2.0 ATA for 1 hour at 0, 24 and 48 hours after exercise, followed by two sham treatments at 72 and 96 hours. (2) same HBOT on five occasions at 0, 24, 48, 72 and 96 hours. CONTROL Sham HBOT by exposure to 1.2 ATA breathing air at 0, 24, 48, 72 and 96 hours for one hour on each occasion.
Outcomes	PAIN SCORE Visual analogue (0 to 10) (estimated from graphical representation). STRENGTH Change from baseline as maximal eccentric torque measured in Nm (estimated from graphical representation).
Notes	Schulz rating: Randomisation ‐ B Allocation concealment ‐ B Completeness of outcome data ‐ C Double‐blinding ‐ A Complex protocol makes interpretation difficult. Most point estimates are derived from graphs with means and SEM. Where results have been given with standard errors, these have been converted to standard deviations. Complex experimental design with 2 distinct phases: see Staples 1999a for phase 1.
Risk of bias
Bias	Authors' judgement	Support for judgement
Allocation concealment?	Unclear risk	B ‐ Unclear