Regional Blood Flow Characteristics in Response to Maximal Voluntary Contractions are Attenuated in Stroke Patients
Format of Original
American College of Sports Medicine
Medicine & Science in Sports & Exercise
PURPOSE: We sought to evaluate the regulation of blood flow to the exercising muscle during maximal voluntary contractions (MVC) in patients having suffered a stroke compared to healthy controls.
METHODS: A pilot investigation of 5 patients having suffered a stroke and 5 controls was performed to assess regional flow patterns via NIRS during MVC with the leg at 90 degrees (Biodex: Shirley, New York). The dominant leg of controls as well as both paretic and non-paretic legs in patients were tested. NIRS values were used to evaluate regional flow in the rectus femoris and reported as a high, low, and percent change during the MVC effort.
RESULTS: Control subjects had a greater peak torque (241.8 ± 32.2 Nm) when compared to the non-paretic leg (87.4 ± 24.8Nm) or paretic leg (59.4 ± 31.4 Nm) of the patients with stroke (ANOVA, p
CONCLUSIONS: Individuals having suffered from a stroke have an attenuated blood flow response as assessed by NIRS monitoring during a MVC maneuver. These findings are not isolated to the paretic leg but exist equally in the non-paretic limb suggesting the potential of global perfusion issues in the patients having suffered a stroke. Further investigation into the mechanisms behind these improvements and the impact on leg function is warranted.