Fig. 9. Comparison of the force and power output by intact white
(Curtin and Woledge, 1988) and
red muscle fibres. Black lines (white fibres) and red lines (red fibres) were
calculated from Hill's equation using the mean values of the fitted constants
in Table 3A (means for seven
white fibre preparations and seven red fibre preparations). (A) The
relationship between relative force and relative velocity calculated from the
following:
P'={[B(P*+A)]/(V'+B)}-A,
where P' is force expressed relative to P0,
the maximum isometric force, V' is velocity expressed relative
to Vmax, the maximum velocity of shortening, which is the
intercept of the force/velocity curve on the velocity axis.
Table 3A includes the values of
the constants:
for red fibres and 1.19±0.04 for white fibres;
A=a/P0=0.269±0.024 for red fibres
and 0.274±0.020 for white fibres;
B=b/Vmax=0.225±0.024 for red
fibres and 0.236±0.022 for white fibres. (B) The relationship between
relative power and relative velocity calculated from the following: relative
power=P'V', where P' and
V' are defined as in A. (C,D) The corresponding relationships
with force expressed in units of force per cross-sectional area and velocity
expressed in units of L0 s-1, where
L0 is the fibre length at which maximum isometric force,
P0, was produced.
