Fig 2. Differences in the selected variables from the six-minute walk test between the Rhodiola crenulata group and placebo (PBO) group over the 12-week treatment period.

*comparison within group: p < .05, comparisons between groups: all p >.05. Solid square symbol: baseline test of the study group, open square symbol: test at 12 weeks of the study group, solid circle symbol: baseline test of the placebo group, open circle symbol: test at 12 weeks of the placebo group, bars: standard error.