Resistance properties of elastic tubing commonly used in rehabilitation and sports training and the effects of previous cyclic loading-unloading.

Abstract

Elastic tubes have been widely used as an external variable resistance in protocols of rehabilitation and sports training. The aim of this study was to evaluate the resistance and effect of fatigue (stiffness reduction) after repeated stretching (cycling) of latex elastic tubing (LET) and natural rubber elastic tubing (NRET). The samples were submitted to axial traction tests at 0, 1000, and 3000 loading-unloading cycles. Each of the respective cycling values consisted of six samples. The loading-unloading cycle reached a 100% maximum strain from the initial length and 1800 mm/min displacement rate; after each test, the samples were loaded monotonically (500 mm/min) to 300% of strain and the force response recorded. The results obtained in this study are similar to the resistance values obtained at 0 cycles reported by the NRET manufacturer (84N vs. 80N), but they do not confirm the report that the “silver” tubing retains the ability to offer resistance after cycling of the elastic tubing for strains of 100% (p = .001), 200% (p = .021), and 250% (p = .002). The LET and NRET showed loss capacity for offering similar resistance (9.5 – 15.5% vs. 9.9 – 15.2%, respectively).