Blood flow responses in the human calf to superficial cold applications and exercise

The purpose of this study was to determine whether a superficial cold application applied prior to and during intermittent maximal isokinetic exercise would affect the vasodilatory response in the plantar-flexor muscles of the calf. Fourteen healthy, uninjured male subjects, of college age, participated in 4 randomized treatments applied on separate days: Control (CO), Ice Pack only (I), Exercise only (EX), and Ice and Exercise (IEX). Ice packs (I) were applied for 23 minutes, Exercise consisted of 5 bouts of resisted plantar-flexion on an isokinetic device, the Cybex. During IEX, an ice pack was applied 10 minutes prior to exercise and between each exercise bout. Heart rate (HR) was measured by ECG. Blood pressure was measured by auscultation and used to calculate mean arterial pressure (MAP). Total calf blood flow (Q) was estimated by impedance plethysmography. Skin temperature (Tsk), HR, MAP, and Q were compared over 3-minute intervals by two-way MANOVA (p $\le$ 0.01) for time and treatments or independent variables. The measurements were also compared individually over time by a repeated measures procedure (p $\le$ 0.01. A priori comparisons far significant effects were made by Dunn's procedure (alpha $<$ 0.05). During I, Q and Tsk were significantly decreased during time of superficial cold application, with no significant change in HR or MAP compared to CO. During EX, Q and HR increased during exercise bouts. During IEX, blood flow was significantly lower without a significant difference associated with the amount of exercise done or effect on HR or MAP compared to EX. Conclusions of this study were: (1) A superficial cold application will decrease blood flow in the human calf, without a central effect on heart rate or blood pressure, compared to control. (2) Blood flow to the calf will increase during intermittent maximal isokinetic exercise of the plantar-flexors with a concomitant increase in heart rate and blood pressure. (3) The blood flow response to exercise alone is higher than when the exercise is combined with superficial cold application applied before and between the intermittent maximal isokinetic exercise.U of I OnlyETDs are only available to UIUC Users without author permissio