Table 3

Comparison of fatigue between the two groups within subgroups categorized by baseline vitamin C level.

Vitamin C Group

(n = 70)

Placebo Group

(n = 71)

p value†

Baseline

2 hours after intervention

1 day after intervention

Baseline

2 hours after intervention

1 day after intervention

Fatigue right now*

Higher

5.74 ± 1.98

5.26 ± 2.23

5.28 ± 2.40

5.47 ± 2.17

5.25 ± 2.30

5.53 ± 2.22

0.206

Lower

5.54 ± 2.09

4.94 ± 1.85

4.66 ± 2.30

5.60 ± 1.99

5.37 ± 1.68

5.80 ± 2.13

0.004

*Fatigue was measured using a numeric rating scale, 0-10.

Higher and Lower groups were divided by 50th percentile (10.95 μg/ml in trial group, 11.95 μg/ml in placebo group) of baseline plasma vitamin C level.

†p value from ANCOVA with adjustments for the time factor and baseline measurements.

Suh et al. Nutrition Journal 2012 11:7   doi:10.1186/1475-2891-11-7