Table 5. Fitted experimental data of pairs of one muscle unit (mU) and one motoneuron (MN) property and subsequent ${\mathit{S}}_{\mathit{m}\mathit{U}}\propto {\mathit{S}}_{\mathit{M}\mathit{N}}^{\mathit{c}}$ relationships.

Species	$\mathit{A}=\mathit{k}\bullet {\mathit{B}}^{\mathit{c}}$(fitted relationships)					(final relationships)
	Relationship	$c$	$r^2$	p-value	Reference studies	c
Rat	${\displaystyle IR=k\cdot AC{V}^c}$	3.4	0.45	6.10-3	Kanda and Hashizume, 1992	2.4
Cat	${\displaystyle F^{tw}=k\cdot AC{V}^c}$	9.4	0.43	<10-5	Knott et al., 1971	6.6
	${\displaystyle F^{tet}=k\cdot AC{V}^c}$	7.2	0.37	<10-5	Mcphedran et al., 1965; Wuerker et al., 1965; Appelberg and Emonet-Dénand, 1967; Proske and Waite, 1974; Bagust, 1974; Jami and Petit, 1975; Stephens and Stuart, 1975; Burke et al., 1982; Emonet-Dénand et al., 1988	5.0
	$F^{tet}=k\bullet R^c$	-1.3	0.27	6.10-5	Dum and Kennedy, 1980	3.2
	$F^{tet}=k\bullet S_{MN}^c$	2.0	0.21	2.10-2	Burke et al., 1982	2.0
Mouse	$F^{tw}=k\bullet R^c$	-2.1	0.42	<10-5	Manuel and Heckman, 2011; Martínez-Silva et al., 2018	5.1
	$F^{tw}=k\bullet I_{th}^c$	1.3	0.64	2.10-4	Manuel and Heckman, 2011	3.3
	$F^{tet}=k\bullet I_{th}^c$	1.0	0.80	6.10-2	Manuel and Heckman, 2011	2.5
Mean ± sd						3.8 ± 1.5