Whitley Stone

Strength and Step Activity After Eccentric Resistance Training in Those With Incomplete Spinal Cord Injuries

Background: Individuals with spinal cord injuries (SCIs) often experience general weakness in the lower extremities that undermines daily step activity. Objective: To investigate the efficacy of eccentrically biased resistance training on lower extremity strength and physical activity of individuals with spinal injuries. Methods: Individuals with long-standing incomplete SCIs (N = 11) capable of completing a 10-meter walk assessment were included. All participants who completed the familiarization period finished the training. Individuals trained two times per week for 12 weeks on a lower body eccentric resistance training machine. It was hypothesized that the outcome variables (eccentric strength, isometric strength, and daily step physical activity) would improve as a result of the training intervention. Results: Eccentric strength [F(1.27, 12.71) = 8.42, MSE = 1738.35, H-F p = .009] and isometric strength [F(1.97, 19.77) = 7.10, MSE = 11.29, H-F p = .005] improved as a result of the training while daily step activity remained unchanged [F(2.00, 18.00) = 2.73, MSE = 216,836.78, H-F p = .092]. Conclusions: Eccentric resistance training improves eccentric and isometric strength. These physiological adaptations may translate to improved gait mechanics, but further study is required to identify this potential crossover effect.

Ambulation and physical function after eccentric resistance training in adults with incomplete spinal cord injury: A feasibility study

Background: Strengthening the lower extremities has shown to positively influence walking mechanics in those with neurological deficiencies. Eccentric resistance training (ERT) is a potent stimulus for the development of muscular strength with low metabolic demand. Thereby, ERT may benefit those with incomplete spinal cord injuries (iSCI) seeking to improve ambulatory capacity. Design: This study was aimed to determine the effect of ERT on walking speed, mobility, independence, and at home function following iSCI. Methods: Individuals with longstanding iSCI trained twice a week for 12 weeks on an eccentrically biased recumbent stepper. Outcome measures: Walking speed (10 meter walk test; 10MWT), mobility (timed up and go), independence (Walking Index for Spinal Cord Injury; WISCI), and at home function (Spinal Cord Independence Measure; SCIM) were assessed at baseline, after 6 weeks, and after 12 weeks of ERT. Results: There were improvements in walking mobility (158.36 + 165.84 seconds to 56.31 + 42.42 seconds, P = .034, d = 0.62), speed (0.34 + 0.42  m/s to 0.43 + 0.50  m/s, P = .005, d = .23), and independence (8 + 7 to 13 + 7, P = .004, d = .73) after 12 weeks of ERT. At home function remained unchanged (22 + 10 to 24 + 10, P = .10, d = .12). Conclusions: Improving lower extremity strength translated to walking performance and independence in those with iSCI. Additionally, ERT may diminish therapist burden in programs designed to improve ambulatory capacity or strength in those with iSCI.