A-36 Free Communication/Poster - Vascular Function: MAY 27, 2009 7:30 AM - 12:30 PM ROOM: Hall 4F
In animal models, muscle damage caused by eccentric contractions instigates an inflammatory response, and reduces local microcirculatory blood flow and vasodilator function. Local alterations in the microcirculation may translate to unfavorable changes in the larger, central blood vessels. Currently, it is unknown if local muscle damage is potent enough to alter macrovascular function in humans.
PURPOSE: To determine whether muscle damage caused by eccentric contractions reduce macrovascular function.
METHODS: Recreationally-active males (n=16, age 24±6 years) participated in a randomized crossover experiment consisting of 2 trials, separated by at least 14 days. Prior to the start of each trial, subjects were familiarized with isometric force and vascular measurements. In each trial, muscle damage was induced using 2×20 unilateral eccentric contractions of the elbow flexors and randomized between dominant and non-dominant arm. Measurements were taken at baseline, and at 1, 24, 48, and 72 hours following the eccentric exercise.
RESULTS: Isometric muscle force was lower (p<0.01), and muscle soreness ratings were higher (p<0.01) than baseline for all time points in both trials. In addition, serum creatine kinase was elevated at 24h and 72h post (p<0.05). Aortic pulse wave velocity, a measure of central arterial stiffness, and aortic augmentation index, a measure of arterial wave reflection, did not change throughout the experimental period despite significant muscle damage to the elbow flexors. In addition, there was no difference in pulse wave velocity or augmentation index between the dominant and non-dominant trials at any time point.
CONCLUSION: Muscle damage to the elbow flexors does not translate to unfavorable changes in central macrovascular function.