Table 2.
Transcranial magnetic stimulation values between stronger and weaker sides.
| Median (range) | Pre training | Post training | 3-month follow up | ||||||
|---|---|---|---|---|---|---|---|---|---|
| TMS variable | Stronger | Weaker | Sig. | Stronger | Weaker | Sig. | Stronger | Weaker | Sig. |
| RMT (MSO%) | 40 (28–68)a | 45 (30–73)a | 0.618 | 37 (22–76) | 48 (26–92) | 0.205 | 43 (24–56)d | 40 (29–81)f | 0.138 |
| AMT (MSO%) | 33 (20–64) | 42 (27–100) | 0.058 | 27 (17–45) | 37 (18.76) | 0.042* | 30 (20–60)e | 31 (21–64)f | 0.307 |
| MEP105%AMT | 231.13 (186.67–331.17) | 415.5 (181.5–464.25)b | 0.046* | 477.18 (243.50–1097.17) | 222.50 (124.17–1072.20) | 0.012 | 374.60 (91.50–634.40)e | 295.88 (165.33–358.67)f | 0.116 |
| MEP115%AMT | 310.00 (96.75–1398.00) | 593.05 (174.00–1130.00)b | 0.463 | 621.21 (319.00–1422.75) | 320.75 (172.75–1720.80) | 0.050 | 430.75 (146.25–1360.50)e | 370.42 (153.00–860.33)f | 0.600 |
| MEP125%AMT | 344.92 (199.50–2640.00) | 818.47 (161.00–1365.77)b | 0.753 | 740.50 (209.47–1592.00) | 510–13 (226.60–3030.33) | 0.779 | 597.40 (213.20–2100.00)e | 772.17 (228.67–1453.75)f | 0.753 |
| MEP135%AMT | 672.58 (248.00–3546.00) | 550.23 (206.00–1483.67)b | 0.345 | 1348.75 (353.33–1722.25) | 665.50 (237.75–3587.33)c | 0.237 | 724.20 (117.00–4664.40)e | 994.67 (232.67–2159.67)f | 0.463 |
| MEP145%AMT | 568.00 (334.50–3727.80) | 564.63 (248.00–1812.67)b | 0.345 | 1784.88 (430.33–4608.00) | 765.67 (310.50–3998.00)c | 0.128 | 1065.67 (272.00–4634.00)e | 1165.08 (260.33–2814.80)f | 0.345 |
| MEP155%AMT | 1037.55 (357.00–3771.33) | 870.67 (468.50–1933.00)b | 0.686 | 2047.85 (373.75–4031.20) | 892.50 (232.33–4268.00)c | 0.091 | 1346.17 (98.00–4669.00)e | 1252.75 (257.20–2798.00)f | 0.249 |
| eREC slope (gain) | 14.80 (3.53–77.38) | 3.14 (−1.83–30.00)b | 0.075 | 28.41 (3.22–82.06) | 10.18 (1.70–66.77)c | 0.091 | 15.51 (0.90–49.28)e | 19.11 (2.24–59.03)f | 0.686 |
| eREC R2 (accuracy) | 0.77 (0.51–0.97) | 0.35 (0.00–0.97)b | 0.173 | 0.76 (.042–0.96) | 0.82 (0.66–0.99)c | 0.499 | 0.78 (0.05–0.87)e | 0.91 (0.82–0.95)f | 0.043* |
| eREC AUC (overall excitation) | 25852 (13182–126385) | 30498 (7558–65129)b | 0.463 | 58744.17 (16940.42–108246.00) | 30189.83 (11258.50–150065.17)c | 0.176 | 34050.50 (8432.00–154112.00)e | 40965.42 (10859.33–83448.00)f | 0.463 |
| CSP105%AMT | 89.56 (34.65–177.40) | 72.47 (50.61–249.76)b | 0.249 | 33.35 (16.17–91.63) | 82.77 (31.92–279.04) | 0.012* | 49.66 (32.80–269.32)e | 75.26 (37.17–229.93)f | 0.249 |
| CSP115%AMT | 118.31 (45.06–181.49) | 102.27 (84.86–266.75)b | 0.345 | 62.34 (19.35–219.98) | 112.16 (40.96–271.27) | 0.036* | 98.03 (18.88–279.07)e | 108.28 (55.22–229.40)f | 0.046* |
| CSP125%AMT | 138.49 (58.90–233.98) | 128.85 (101.84–255.44)b | 0.116 | 71.41 (44.46–190.77) | 148.58 (52.44–307.23) | 0.017* | 124.91 (45.60–186.06)e | 169.13 (87.86–259.93)f | 0.046* |
| CSP135%AMT | 151.60 (67.87–237.88) | 150.01 (121.46–272.03)b | 0.345 | 83.57 (40.51–201.44) | 140.24 (73.29–292.23)c | 0.018* | 142.76 (47.85–304.16)e | 170.69 (77.56–225.96)f | 0.173 |
| CSP145%AMT | 157.33 (82.26–282.32) | 151.81 (139.38–325.93)b | 0.173 | 137.96 (67.22–238.43) | 159.61 (94.94–347.51)c | 0.018* | 167.32 (123.66–316.11)e | 175.15 (83.65–252.69)f | 0.345 |
| CSP155%AMT | 174.75 (101.28–294.92) | 158.33 (146.92–187.09)b | 0.893 | 143.82 (66.13–257.88) | 156.08 (129.73–233.08)c | 0.028* | 156.71 (121.33–179.94)e | 169.94 (149.51–293.69)f | 0.046* |
| iREC slope (Gain) | 1.88 (0.91–3.68) | 1.84 (0.83–2.19)b | 0.893 | 2.04 (0.89–2.56) | 1.97 (0.29–2.88)c | 0.866 | 2.17 (0.75–2.73)e | 1.76 (1.03–2.27)f | 0.345 |
| iREC R2 (accuracy) | 0.94 (0.75–0.99) | 0.88 (0.84–0.99)b | 0.893 | 0.88 (0.67–0.97) | 0.87 (0.01–0.95)c | 0.237 | 0.90 (0.73–0.93)e | 0.70 (0.54–0.79)f | 0.028* |
| iREC AUC (overall Inhibition) | 6975.5 (3262.0–11718.0) | 6531.5 (5823.00–12450.30)b | 0.249 | 4369.13 (2271.20–10254.75) | 6666.25 (3601.05–13043.85)c | 0.018* | 5857.20 (3397.85–7825.15)e | 7482.20 (3976.30–12292.90)f | 0.116 |
| MEP latency (ms) | 24.17 (21.38–43.15)a | 26.26 (20.45–35.52)a | 0.866 | 24.51 (19.48–43.78) | 25.95 (20.36–38.02) | 1.000 | 22.12 (21.88–29.69)e | 25.97 (20.26–28.20)f | 0.686 |
AMT, active motor threshold; CSP, cortical silent period; eREC, excitatory recruitment curve; iREC, inhibitory recruitment curve; MEP, motor evoked potential; MSO%, maximal stimulator output percentage; RMT, resting motor threshold; eREC Slope = MEP Amplitude (μV) by TMS intensity105−155%AMT; iREC Slope = CSP time (ms) by TMS intensity105−155%AMT; Area under the curve (AUC) was calculated for both excitatory and inhibitory RECs using the trapezoid rule ΔX x (Y1+Y2)/2, whereby X were the MSO% used (i.e., X axis values, 105–155% of AMT) and Y are the recorded CSP lengths (ms) or the MEP amplitudes (μV).
Difference between stronger and weaker hand is statistically significant at α <0.05.
Missing data from participant 2 due to too low corticospinal excitability (i.e., no resting MEPs).
Missing data from participant 2 and 7 due to too high AMT (AMT = 100 and 82%, respectively), thus the required increases in MSO% based on AMT to assess the REC could not be performed).
Missing data from participant 7 due to high AMT (AMT = 76%), thus the required intensities of 135–155% of AMT could not be performed, and the slope, R2 and AUC could not be calculated).
Time point with n = 5 (participant 2 could not be reached during follow-up assessment, missing data from participant 7 and 6 due to too low corticospinal excitability (i.e., no resting MEPs) and overheating of equipment (i.e., stimulator).
Missing data from participant 2 (could not be reached during follow-up).
Missing data from participant 2 (could not be reached during follow-up) and 7 [too low corticospinal excitability (i.e., no resting or contracting MEPs (RMT and AMT)].