Mean stiffness values during length changes.

<p>Mean stiffness values (± S.E.M) during isometric contraction (black bar), shortening (light grey bar) and stretch (dark grey bar) obtained in experiments performed in pCa²⁺4.5 before and after MgADP treatment (n = 7). MgADP did not affect stiffness, but in stiffness was always increased during stretch and decreased during shortening. * Significantly different from isometric contractions,^# significantly different from shortening.