Figure 5. Diaphragmatic tissue mechanical parameters.

A, typical stress–relaxation curve following stretch of a diaphragmatic strip. The stress (σ) increased when the strain ramp was applied until attainment of the strain peak; thereafter, the tissue relaxed while the stress decreased to an equilibrium value during the constant strain phase. Stress–relaxation data allow calculation of elastic moduli E_t and the relaxation time constants (τ) for all of the tested strain levels. B, average values of the elastic modulus (E_t) for increasing strain (ɛ) level, expressed as percentage of initial strip length, of all the tested specimens (n = 28). C, average values of the first relaxation (τ₁) constant (n = 28). Bars represent means ± s.e.m. *Significantly different (P < 0.01) from values at 5% strain; ^§significantly different (P < 0.01) from values at 10% strain.