Eccentric Resistance Training in Adults with and without Spinal Cord Injuries

Abstract

International Journal of Exercise Science 10(1): 154-165, 2017The purpose of this study was to examine the effects of active lower body eccentric resistance training (ERT) in individuals with incomplete spinal cord injury (iSCI) and controls (CON). Specifically, the study was designed to determine if those with iSCI adapt similarly to ERT as CON participants as well as the overall safety and efficacy of ERT in this population. This pilot investigation involved the recruitment of persons with iSCI (n = 3) and age-and sex-matched able-bodied CON (n = 3). The 8-week intervention focused on building lower extremity eccentric strength by progressively increasing the duration and intensity of training sessions. Control participants completed the same training intervention. Main outcome measures were eccentric strength (eccentric ergometer), isometric strength (hand held dynamometer), and leg muscle mass (DEXA). All participants completed the ERT. At posttest, eccentric strength improved from pretest (p = .044, p 2 = .68) with similar changes between groups (p > .05). The percent improvement in isometric strength for those with iSCI (41.5%) was different than CON (-2.8%) after training (p = .044). Neither group demonstrated muscle mass gains at posttest (p > .05). Active lower body ERT is well tolerated and effective at increasing lower extremity strength in those with iSCI. These adaptations are likely attributable to neuromuscular development rather than a hypertrophic response.

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

“…In support of previous work, 26 data from the current study support the contention that individuals with iSCI have the capacity to improve neuromuscular function of the affected limbs similarly to unimpaired individuals. Our participants with iSCI showed similar improvements as young, healthy men who completed 35 ERT training sessions on a knee extension machine (~39%) 27 and neurologically intact men who completed 8 weeks of unilateral knee extensors (~29%) ERT.…”

“…Previously, Stone et al 26 utilized the same training ergometer in a sample of individuals with iSCI who would be described as daily ambulators (one cervical and two thoracic iSCIs). Here, improvements in eccentric strength averaged 79% following an 8-week ERT.…”

“…An a priori power computation indicated that the analyses would be powered at 80% when 10 participants completed the ERT (G*Power, Version 3.1) based on measured effect sizes reported previously in a similar participant pool. 26 IBM Statistics for Windows, Version 23.0 (IBM Corp., Armonk, NY) was used to analyze data. Three one-way repeated measures analyses of variance (ANOVAs) were used to evaluate the impact of ERT (baseline, midtraining, and posttraining) on isometric strength, eccentric strength, and average daily step PA. An a priori familywise alpha of p < .05 was used.…”

The “Journal of Functional Morphology and Kinesiology” Journal Club Series: Highlights on Recent Papers in Strength and Conditioning

“…These authors have shown that in patients with severe COPD, 10 weeks of EET led to increases in muscle strength and hypertrophy, at progressively lower levels of perceived fatigue and dyspnea. Similar applications of EET have led to increased lower limb strength in patients with spinal cord injuries [4] and EET is as successful as traditional rehabilitation when addressing fall risks in elderly subjects [5]. The physiological adaptation stimulated by EET in clinical populations has the potential to extend to healthy subjects and in particular to competitive sport, where the continuous search for training methods to enhance performance is paramount.…”

Walker vs. Wheelchair User: Expected Gains from Lower Extremity Eccentric Resistance Training after Incomplete Spinal Cord Injury

“…The eccentric muscle action (generation of tension as the muscle lengthens) consumes less oxygen per unit of work, thus allowing individuals with low cardiovascular ceilings to exercise at higher volumes compared to traditional eccentric + concentric repetitions. Those with incomplete spinal cord injury (iSCI) [11][12] [13] and other neurological conditions [14] [15] have safely performed ERT in adjunct to traditional therapeutic interventions. Outcomes from these studies include improved eccentric and isometric strength, walking function, quality of life, cardiovascular fitness, and muscle volume.…”