Acute cardiovascular and cerebral blood flow responses to high frequency, low amplitude vibration on the neck.

Local muscle vibration (LMV) is a potential therapeutic approach to treat symptoms related to stroke by improving muscle function and blood flow. In this study, we assessed the acute cardiovascular and cerebral blood flow responses to LMV when applied to the anterior neck muscles in young and healthy participants. We hypothesized that LMV would elicit minimal acute cardiovascular responses. Ten human participants (5 male, 5 female) underwent LMV on both sides of their neck for 5-min each. Arterial pressure, middle cerebral artery blood velocity (MCAv), and common carotid artery (CCA) blood flow were measured continuously. There was no effect of LMV on mean arterial pressure (RIGHT, Baseline: 96.9±4.9 mmHg vs. LMV: 97.8±5.7 mmHg vs. Recovery: 98.2±4.6 mmHg, P=0.25; LEFT, Baseline: 96.0±7.8 mmHg vs. LMV: 97.0±7.7 mmHg vs. Recovery: 97.9±7.5 mmHg; P=0.23) or MCAv (RIGHT, Baseline: 61.4±10.5 cm/s vs. LMV: 62.0±10.7 cm/s vs. Recovery: 59.3±9.7 cm/s; P=0.15; LEFT, Baseline: 59.9±10.2 cm/s vs. LMV: 60.6±10.8 cm/s vs. Recovery: 58.4±10.2 cm/s; P=0.20). CCA diameter increased slightly with LMV on both sides of the neck (RIGHT, Baseline: 6.2±0.6 mm vs. LMV: 6.3±0.7 mm, P=0.03; LEFT, Baseline: 6.4±0.5 mm vs. LMV: 6.5±0.5 mm, P=0.03). However, this did not affect CCA blood flow (RIGHT, Baseline: 330.7±68.5 ml/min vs. LMV: 324.7±57.6 ml/min, P=0.59; LEFT, Baseline: 358.1±67.5 vs. LMV: 344.2±78.3 ml/min, P=0.30). These data provide evidence that a single acute session of LMV does not affect key cardiovascular parameters in young and healthy participants.