Thermal Effects on Bovine-Tendon Elasticity: Implications for Provocative Elongation Techniques

Objective: To explore changes in bovine Achilles-tendon elasticity relative to 3 thermal conditions. Design and Setting: Posttest-only design with assignment by convenience. Manufactured-apparatus-clamped excised tendon, delivered tensile stress, and provided strain measures. Stress was increased at 1-minute intervals. Strain was observed for each level of stress. Before testing, cold-group tendons were submerged in cold water for 20 minutes. Heat-group tendons were tested in the presence of an ultraviolet lamp. A third group of tendons was tested at room temperature. Subjects: Frozen bovine Achilles tendons provided by a meat-rendering factory and segmented into 3 longitudinal strips. Measurements: Stress and strain were sequentially measured. Elastic region was identified, elastic-region Young's modulus determined, and elastic limit calculated. Results: Young's modulus for cold was 0.956 gigapascal (GPa; ± 0.0621); room temperature, 0.753 GPa (± 0.0624); and heat group, 0.487 GPa (± 0.0407). Significant...