Blunting blood pressure during exercise in humans with hypertension
Research type
Research Study
Full title
Blunting the blood pressure response to exercise in humans with hypertension
IRAS ID
226407
Contact name
Emma Hart
Contact email
Sponsor organisation
University of Bristol
Duration of Study in the UK
1 years, 3 months, 1 days
Research summary
High blood pressure (hypertension) is a common condition, affecting one quarter of all adults in the UK. Exercise training is an effective component of life style alteration that has been shown to lower blood pressure in hypertensive individuals. Individuals with an exaggerated blood pressure response to exercise are at increased risk of adverse cardiovascular events. Worryingly, individuals who have controlled blood pressure at rest by anti-hypertensive medication(s) have an exaggerated blood pressure response to exercise similar to individuals with untreated hypertension and uncontrolled blood pressure. During exercise in both people with hypertension and normal blood pressure, the rise in blood pressure is mediated by a reflex called the exercise pressor reflex. This reflex is made up of two components 1) the metaboreflex and 2) the mechanoreflex. These reflexes increase the activity of the nervous system which increases heart rate and blood pressure. The metaboreflex is overactive in individuals with controlled hypertension and may be mediating the blood pressure response to exercise in this population.
Dietary nitrates in the form of beetroot juice have been shown to lower resting blood pressure in humans with hypertension. Little is known about the effect of beetroot juice on the blood pressure response to exercise in this population.
This study will involve four visits to the CRIC, Bristol. We will use people with controlled blood pressure by anti-hypertensive medication. Pre-assessment one will involve screening, pre-assessment two will involve handgrip exercise with an occlusion cuff to measure the metaboreflex and a test of current fitness level (VO2 peak test). An occlusion cuff is a blood pressure monitor pumped up high on the upper arm to stop blood leaving the arm for a short period of time (3 minutes). The participant will then supplement with beetroot juice for 4 weeks before coming back to repeat the tests.
REC name
HSC REC B
REC reference
17/NI/0097
Date of REC Opinion
30 May 2017
REC opinion
Further Information Favourable Opinion