Immediate effects of cervical spine manipulation on upper extremity ergometer performance to muscle failure amongst asymptomatic participants - upper limb endurance and manipulation

Objective: The purpose of the study was to determine if cervical spinal manipulative therapy (SMT) impacted upper extremity ergometer performance to muscle failure amongst asymptomatic participants. Methods: Forty-six healthy chiropractic college students were randomized into three study groups using an AB:BA crossover study design with an additional control arm (BB). Each week, of the two-week protocol, participants engaged in a Monark; upper extremity ergometer test at 50 W resistance for females and 100 W for males while maintaining 50 rpm until muscle failure. Group 1(AB) received cervical SMT prior to testing during week one and no SMT prior to testing during week two. Similarly, Group 2(BA) received no SMT week one and SMT week two. Group 3(BB) did not receive SMT either week. Exercise time to exhaustion, exercise heart rate, blood lactate, post 1-min Rating of Perceived Exertion (RPE), and post 5-min RPE were recorded during each session. A paired samples t-test was used to make comparisons between A and B conditions, and to track test acclimation in the BB group. Results: There was no statistically significant difference between SMT and no-SMT conditions for time to exhaustion (p=0.712), heart rate (p=0.220), blood lactate (p=0.462), post 1-min RPE (0.804) and post 5-min RPE (0.561); however, the week that participants received cervical SMT their heart rate was 8.5 beats higher than the week they did not at test completion. Conclusions: Preliminarily, this research demonstrates that cervical SMT does not impact upper extremity ergometer performance amongst asymptomatic participants to a statistically significant level.