Table 1. Twitch parameters before and... | Rockefeller University Press

Table 1.

Twitch parameters before and after a PS in mouse lumbrical muscle at 37°C

Twitch parameter	Pre-PS	Post-PS		Relative change (Post-PS/Pre-PS)
	−60 s	2.5 s	30 s	2.5 s	30 s
Amplitude (mN)	16.23 ± 1.51	18.87 ± 1.61^a	16.61 ± 1.50^b	1.17 ± 0.03^a	1.03 ± 0.01^b
Time to peak (ms)	11.39 ± 0.40	10.0 ± 0.32^a	10.70 ± 0.42^a^b	0.88 ± 0.01^a	0.94 ± 0.01^a^b
1/2 RT (ms)	12.16 ± 0.69	11.41 ± 0.73^a	11.25 ± 0.72^a	0.94 ± 0.02^a	0.92 ± 0.01^a^b
+dF/dt (mN/ms)	3.41 ± 0.31	4.57 ± 0.42^a	3.60 ± 0.33^b	1.34 ± 0.02^a	1.05 ± 0.01^a^b
−dF/dt (mN/ms)	−1.14 ± 0.11	−1.40 ± 0.13^a	−1.23 ± 0.11^a^b	1.23 ± 0.04^a	1.08 ± 0.01^a^b

Twitch parameter	Pre-PS	Post-PS		Relative change (Post-PS/Pre-PS)
	−60 s	2.5 s	30 s	2.5 s	30 s
Amplitude (mN)	16.23 ± 1.51	18.87 ± 1.61^a	16.61 ± 1.50^b	1.17 ± 0.03^a	1.03 ± 0.01^b
Time to peak (ms)	11.39 ± 0.40	10.0 ± 0.32^a	10.70 ± 0.42^a^b	0.88 ± 0.01^a	0.94 ± 0.01^a^b
1/2 RT (ms)	12.16 ± 0.69	11.41 ± 0.73^a	11.25 ± 0.72^a	0.94 ± 0.02^a	0.92 ± 0.01^a^b
+dF/dt (mN/ms)	3.41 ± 0.31	4.57 ± 0.42^a	3.60 ± 0.33^b	1.34 ± 0.02^a	1.05 ± 0.01^a^b
−dF/dt (mN/ms)	−1.14 ± 0.11	−1.40 ± 0.13^a	−1.23 ± 0.11^a^b	1.23 ± 0.04^a	1.08 ± 0.01^a^b

All data are presented as mean ± SEM (n = 10 muscles). Time markers correspond to 60 s before start and 2.5 and 30 s after the PS (20 Hz for 2.5 s). Peak twitch force occurred at 2.5 s after the PS in every muscle examined; all data collected at optimal length for twitch force (L_o). Data corresponds to ICT data presented in Table 2. Amplitude, twitch force from baseline to peak; time to peak, the time for force to rise from baseline to peak; 1/2 RT, time for force to relax from peak to 50% peak; +dF/dt, maximum rate of force production; −dF/dt, maximum rate of force relaxation.

Post-PS value at 2.5 or 30 s significantly different than pre-PS value (P < 0.05).

Post-PS value at 30 s significantly different than post-PS value at 2.5 s (P < 0.05).

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