Table 1.

Comparison of cross-bridge kinetics

	Myofibrils	Muscle fibres	Units
Tension	122 ± 18	137 ± 8	kPa
2πa	1.5 ± 0.3	3.3 ± 0.2	s−1
2πb	98 ± 7	53 ± 4	s−1
2πc	166 ± 15	201 ± 12	s−1
A	3.6 ± 0.7	4.7 ± 0.5	MPa
B	9.3 ± 2.0	7.1 ± 0.8	MPa
C	10.1 ± 2.1	8.0 ± 0.8	MPa
Y∞	4.4 ± 0.8	7.5 ± 0.5	MPa
Rigor stiffness	5.1 ± 0.9	7.6 ± 0.5	MPa
Number of experiments	12	7

Data are means ± SEM. These parameters were measured in 1S activating solution (pCa 4.40, 1 mm MgATP, 1 mm Mg²⁺, 8 mm P_i, 200 mm ionic strength).