Table 3 Modified parameter values of the previously published model components

G _Na

Maximum conductance of fast Na⁺ current (mS/μF)

Increasing dV/dt_max of V_m

14.5

Maximum Ca²⁺ transport rate of PMCA (pA/pF)

Adjusting Ca²⁺ circulation fraction

0.05

G _Cab

Conductance of background Ca²⁺ current (mS/μF)

Adjusting SR calcium content

3.4 × 10^-4

Maximum conductance of NKA (pA/pF)

Matching to recent data of ref. [67]

1.4

K _{m, Nai}

Half maximal [Na⁺]_i sensitive activation (mM)

(same as above)

18.6

n _NKA

Exponent of NKA Hill equation

(same as above)

3.2

Ca²⁺ on-rate for troponin high-affinity sites (μM^-1ms^-1)

Adapted from ref. [81]

2.37 × 10^-3

Ca²⁺ off-rate for troponin high-affinity sites (ms^-1)

(same as above)

3.2 × 10^-5

Ca²⁺ on-rate for troponin low-affinity sites (μM^-1ms^-1)

Lowering of the baseline tension according to data of [21, 22]

0.07

SL

Sarcomere length (μm)

Adapted from ref. [22]

2.0

f _φ

Scaling factor for the speed of contraction generation'(see eq. A111 in ref.)

Matching the force transient to data of refs. [21, 22]

2.3

Scaling factor for the half maximal transition rate of tropomyosin from permissive to nonpermissive (see eq. A112 and A113 in ref.)

(same as above)

2.8