Fig. 9. Strain magnitude calculated from simple bending beam theory accurately predicts axial strain measured by sonomicrometry (blue line; P=0.0001; r²=0.9163; N=22). Blue circles represent observations from steady swimming, fast-starts, and sprinting in several species of fish (Coughlin et al., 1996; Katz et al., 1999; Wakeling and Johnston, 1999; Ellerby and Altringham, 2001). Tuna steady swimming, represented by red circles, are excluded from the regression because of their specialized myotendinous architecture (Shadwick et al., 1999; Katz et al., 2001). Fast-start data from this study are superimposed onto this figure: strains calculated at the anterior position (squares) and the posterior position (triangles) are shown for weaker responses (light blue) and stronger responses (dark blue and red). Note that only the posterior location under high strain lies outside the 95% confidence interval that contains the one-to-one predictor (gray line). Standard errors of the mean are only shown for the present study for brevity. Figure adapted from Long et al. (2002).