Table 1.
Mean ± sd of the PPG amplitude and components' amplitude ratios for each phase of the protocol (C, control foot; T, test foot).
| Test foot | Control foot | p (baseline, C vs. T) | p (challenge, C vs. T) | p (recovery, C vs. T) | |||||
|---|---|---|---|---|---|---|---|---|---|
| Baseline | Challenge | Recovery | Baseline | Challenge | Recovery | ||||
| PPG amplitude (AU) | 123.6 ± 69.5 | 15.3 ± 14.2 | 62.7 ± 29.3 | 154.5 ± 120.9 | 106.4 ± 89.7 | 107.7 ± 102.0 | 0.320 | 0.010* | 0.040* |
| – | 0.010* | 0.003* | – | 0.018* | 0.003* | ||||
| Cardiac (%) | 19.6 ± 11.3 | 3.7 ± 3.8 | 10.0 ± 5.7 | 22.5 ± 13.6 | 18.2 ± 18.2 | 16.4 ± 16.4 | 0.514 | <0.001* | 0.178 |
| – | 0.002* | 0.002* | – | 0.010* | 0.003* | ||||
| Respiratory (%) | 3.7 ± 1.9 | 3.2 ± 2.4 | 6.8 ± 5.3 | 2.6 ± 0.9 | 3.2 ± 1.4 | 3.2 ± 1.7 | 0.128 | 0.478 | <0.001* |
| – | 0.182 | 0.020* | – | 0.012* | 0.077 | ||||
| Myogenic (%) | 14.0 ± 8.4 | 7.9 ± 5.1 | 14.0 ± 7.0 | 11.8 ± 5.6 | 11.3 ± 6.4 | 15.3 ± 7.4 | 0.630 | 0.060 | 0.630 |
| – | 0.023* | 0.969 | – | 0.182 | 0.008* | ||||
| Sympathetic (%) | 11.1 ± 4.5 | 6.4 ± 3.4 | 21.1 ± 4.6 | 15.5 ± 5.4 | 14.5 ± 4.4 | 15.3 ± 5.3 | 0.095 | <0.001* | 0.020* |
| – | 0.013* | 0.003* | – | 0.011* | 0.050 | ||||
| Endothelial NO-dependent (%) | 10.2 ± 4.3 | 6.1 ± 2.5 | 10.5 ± 3.4 | 14.5 ± 4.8 | 25.4 ± 9.8 | 17.9 ± 6.7 | 0.069 | <0.001* | 0.004* |
| – | 0.028* | 0.530 | – | 0.003* | 0.583 | ||||
| Endothelial NO-independent (%) | 11.0 ± 4.6 | 14.4 ± 2.9 | 6.8 ± 2.5 | 12.7 ± 6.3 | 12.0 ± 5.7 | 16.6 ± 7.4 | 0.671 | 0.178 | <0.001* |
| – | 0.012* | 0.010* | – | 0.423 | 0.006* | ||||
Statistical comparison with baseline for each foot, and comparison between feet (
*
p < 0.05).