. 2022 Nov 23;128(6):1663–1682. doi: 10.1152/jn.00342.2022

Table 3.

Transspinal evoked potential recruitment curve sigmoid function parameters for the different protocols for thigh muscles

	L-MH	R-MH	L-RF	R-RF	L-GRC	R-GRC	L-VL	R-VL
Stimulation intensity at threshold (TEPth)*
P-KLAB^a	1.00 ± 0.00	1.00 ± 0.00	1.00 ± 0.00	1.00 ± 0.00	1.00 ± 0.00	1.00 ± 0.00	1.00 ± 0.00	1.00 ± 0.00
P-2^b	1.26 ± 0.04	1.36 ± 0.03	1.27 ± 0.10	1.34 ± 0.11	1.26 ± 0.03	1.27 ± 0.06	1.21 ± 0.13	1.37 ± 0.08
P-3^a	0.97 ± 0.05	1.00 ± 0.06	0.93 ± 0.05	0.97 ± 0.03	0.93 ± 0.05	0.96 ± 0.04	1.11 ± 0.02	0.99 ± 0.07
P-4^c	1.57 ± 0.10	1.75 ± 0.10	1.52 ± 0.15	1.55 ± 0.36	1.73 ± 0.08	1.57 ± 0.09	1.79 ± 0.08	1.41 ± 0.20
Stimulus required to elicit TEP equivalent to 50% of TEPmax (S50)
P-KLAB	1.18 ± 0.013^a	1.27 ± 0.034^a	1.48 ± 0.13^a	1.24 ± 0.04^a	1.19 ± 0.016^a	1.25 ± 0.028^a	1.57 ± 0.17^a,b	1.33 ± 0.07^a
P-2	1.53 ± 0.061^b	1.72 ± 0.092^b	1.54 ± 0.08^a	1.94 ± 0.05^b	1.61 ± 0.072^b	1.59 ± 0.059^b	1.95 ± 0.25^a	1.95 ± 0.19^b
P-3	1.15 ± 0.070^a	1.24 ± 0.084^a	1.32 ± 0.95^a	1.23 ± 0.07^a	1.13 ± 0.056^a	1.27 ± 0.083^a	1.33 ± 0.06^b	1.16 ± 0.03^a
P-4	2.18 ± 0.18^c	1.81 ± 0.085^b	2.30 ± 0.12^b	2.13 ± 0.29^b	2.15 ± 0.039^c	2.01 ± 0.086^c	1.91 ± 0.23^a	2.00 ± 0.23^b
m parameter of function
P-KLAB	10.8 ± 0.66^a	8.70 ± 1.02^a,b	7.56 ± 1.89^a	7.59 ± 1.39^a	10.7 ± 1.16^a	8.30 ± 0.95^a	4.43 ± 1.09^a	7.85 ± 1.95^a
P-2	7.52 ± 0.94^a,b	5.98 ± 0.77^a	7.41 ± 1.42^a	4.31 ± 0.76^a,b	6.23 ± 0.48^b,c	5.83 ± 0.62^a,b	6.81 ± 2.45^a	5.94 ± 1.80^a,b
P-3	9.29 ± 1.32^a	9.39 ± 1.21^b	9.26 ± 2.07^a	9.81 ± 2.52^a	10.5 ± 1.51^a,b	8.32 ± 1.25^a,b	8.09 ± 1.97^a	12.1 ± 2.56^a
P-4	5.13 ± 1.25^b	5.87 ± 0.80^a,b	4.28 ± 0.95^b	3.88 ± 1.31^b	5.29 ± 0.63^c	4.53 ± 0.45^b	4.92 ± 1.58^a	3.94 ± 0.63^b
Slope
P-KLAB	0.18 ± 0.013^a	0.27 ± 0.034^a	0.48 ± 0.13^a,b	0.24 ± 0.047^a	0.19 ± 0.016^a	0.25 ± 0.02^a	0.57 ± 0.17^a	0.33 ± 0.07^a,b
P-2	0.27 ± 0.028^a	0.40 ± 0.056^a	0.32 ± 0.06^a	0.52 ± 0.11^b,c	0.31 ± 0.019^a	0.39 ± 0.04^a,b	0.45 ± 0.17^a	0.57 ± 0.19^a,c
P-3	0.17 ± 0.022^a	0.25 ± 0.032^a	0.39 ± 0.11^a	0.26 ± 0.061^a,b	0.17 ± 0.016^a	0.27 ± 0.04^a	0.28 ± 0.05^a	0.20 ± 0.05^b
P-4	0.32 ± 0.055^a	0.35 ± 0.048^a	0.64 ± 0.14^b	0.58 ± 0.17^c	0.42 ± 0.054^a	0.48 ± 0.05^b	0.40 ± 0.10^a	0.59 ± 0.09^c

Averaged values (mean ± SE) of the predicted parameters from the sigmoid function fitted to the data for each transspinal evoked potential (TEP) recruitment curve. The values of the stimulation intensity corresponding to the TEP threshold (TEPth) for all configurations are presented as multiples (MTs) of the TEP threshold of the KNIKOU-LAB4Recovery protocol (P-KLAB). Since the raw stimulation intensity was normalized to the homonymous predicted TEPth observed for the P-KLAB for each TEP separately, the TEPth values for the P-KLAB are 1 MT. Lower case letter displays of Tukey’s multiple comparisons tests report significant pairwise comparisons. Based on Tukey’s multiple comparison tests of the simple effects of protocol at the levels of muscle factor, averaged values with no letter in common are significantly different at 5% level of significance. When the same subscripted letter does not appear at each row, then there is a significant difference between the protocols. For example, m parameter of function for L-MH TEP is significantly different between P-KLAB and protocol 4 (P-4) because they do not have the same letter. Similarly, m parameter of function for L-MH TEP is not different between P-KLAB and protocol 3 (P-3) because they share the same letter. *For the TEPth variable a significant interaction between muscle and protocol was not found. GRC, gracilis; L, left; MH, medial hamstring; P-2, protocol 2; R, right; RF, rectus femoris; VL, vastus lateralis.