The Effects of Dietary Salt on Post-exercise Hypotension
- Conditions
- Blood PressurePost-Exercise Hypotension
- Interventions
- Other: PlaceboOther: High dietary salt
- Registration Number
- NCT03565653
- Lead Sponsor
- University of Delaware
- Brief Summary
The new American Heart Association (AHA) blood pressure guidelines are expected to raise the prevalence of high blood pressure to \~46% in the United States. One recommendation for lowering blood pressure is aerobic exercise, which produces a period of lowered blood pressure (post-exercise hypotension; PEH) that lasts up to 24 hours. It is believed that PEH may be responsible for the observations of lowered blood pressure following initiation of exercise. However, most Americans eat too much salt, which expands plasma volume and may prevent PEH, rending aerobic exercise ineffective in improving blood pressure status.
- Detailed Description
Recently released blood pressure guidelines from the American Heart Association and American College of Cardiology are expected to raise the prevalence of hypertension in America from \~33% to \~46%. A single bout of aerobic exercise produces a prolonged period (up to 24 hours) of lowered blood pressure (post-exercise hypotension; PEH). Repeated bouts of aerobic exercise results in maintenance of lowered blood pressure, leading to recommendations of aerobic exercise for improvement of blood pressure status. However, more than 90% of Americans consume more sodium in their diets than is recommended. This is alarming, as excess dietary sodium intake expands plasma fluid volume, which may in turn attenuate the reduction in BP following exercise. Therefore, the objective of this project is to determine the effects of high dietary sodium intake on PEH. The investigators hypothesize that, compared to a recommended sodium diet, a high salt diet will attenuate post-exercise hypotension.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 20
- Recreationally active
- high blood pressure (>140/90 mmHg)
- history of cardiovascular disease
- history of cancer
- history of diabetes
- history of kidney disease
- obesity (BMI > 30 kg/m2)
- smoking or tobacco use
- current pregnancy
- nursing mothers
- communication barriers
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- CROSSOVER
- Arm && Interventions
Group Intervention Description Placebo Placebo For 10 days each, participants will be asked to eat a recommended sodium diets (2300 mg Na+/d) while taking unmarked pills containing a placebo (dextrose). Participants will complete both interventions in random order. On the 10th day, participants will report to the lab to complete 60 minutes of cycling exercise. Following exercise, participants will rest for 60 minutes while undergoing serial blood pressure measurements. Participants will then be outfitted with ambulatory blood pressure cuffs for assessment of blood pressure over the following 24 hours. High dietary salt High dietary salt For 10 days each, participants will be asked to eat a recommended sodium diets (2300 mg Na+/d) while taking unmarked pills containing uniodized table salt. On the 10th day, participants will report to the lab to complete 60 minutes of cycling exercise. Following exercise, participants will rest for 60 minutes while undergoing serial blood pressure measurements. Participants will then be outfitted with ambulatory blood pressure cuffs for assessment of blood pressure over the following 24 hours.
- Primary Outcome Measures
Name Time Method Post-exercise hypotension 24 hours following exercise Change in mean arterial pressure from pre- to post-exercise
- Secondary Outcome Measures
Name Time Method Blood pressure reactivity 10th day of high salt diet Change in mean, systolic, and diastolic blood pressure from baseline to exercise
Trial Locations
- Locations (1)
Department of Kinesiology and Applied Physiology, University of Delaware
🇺🇸Newark, Delaware, United States