Exploring the Efficacy of Using Ischemic Preconditioning (IPC) to Improve Neural Recruitment During Resistance Exercise After Spinal Cord Injury (SCI).

The relationship between ischemic preconditioning and performance measures in able-bodied athletic populations have been thoroughly studied within the literature and demonstrated significant performance improvements. However, there is currently only one human study investigating how IPC can impact performance measures in individuals with a spinal cord injury (SCI). The mechanism that influences these performance improvements is still not fully understood. The purpose of this study was to investigate the effects of IPC in this population on performance measures, muscular force, and neural contribution. This study utilized 4 participants who have experienced a SCI. The study design was a repeated-measures, cross-over model. It consisted of an IPC (220mmHg) and SHAM (20mmHg) condition in random order. Functional measures of skeletal muscle force and neural measures with surface electromyography were recorded. The performance measures were maximum voluntary contractions (MVC) of the forearm muscles and a time to task failure (TTF) handgrip test. Results: IPC did not improve performance output between both conditions in a TTF handgrip test (IPC: 25.295±10.371 mins; SHAM: 20.958±7.621 mins). IPC did not improve muscular force recorded as MVC (IPC: 571.38 241.83 N; SHAM: 543.32±210.89 N). IPC did not improve neural recruitment suggested in root mean square (RMS) values during the TTF handgrip test in both measured muscles, the flexor carpi radialis (FCR) and the flexor carpi ulnaris (FCU), (FCR RMS: p = 0.564; FCU RMS: p = 0.863). More data is need for statistical relevance and to determine if there is a relationship between IPC and performance in individuals who have experienced a SCI, and if neural contribution plays a role.