Ischemic Preconditioning, Dietary Exposure
Conditions
Brief summary
This study will examine two separate interventions: 1) the effects of ischemic preconditioning or 2) a high fat meal on the capacity of the brachial artery to overcome sympathetic activation and dilate during exercise (also known as functional sympatholysis). Participants will be asked to complete rhythmic handgrip exercise with and without the application of -20 mmHg lower body negative pressure to increase sympathetic activation. Doppler ultrasound will be used to continuously measure brachial artery blood flow. Participants will complete the handgrip exercise and lower body negative pressure before and after the applications of each interventions. Participants may elect to only complete one intervention rather than complete both protocols. Intervention one is active or control ischemic preconditioning. Intervention two is high or low fat meals.
Interventions
PROCEDUREIschemic preconditioning
Four 5-minute cycles of 200 mmHg cuff inflation of the brachial artery, each separated by 5-minutes deflated recovery (i.e. 40 minutes total time)
PROCEDUREIschemic preconditioning control
Four 5-minute cycles of 20 mmHg cuff inflation of the brachial artery, each separated by 5-minutes deflated recovery (i.e. 40 minutes total time)
DIETARY_SUPPLEMENTLow fat meal
Meal containing 1006 calories, 1 g fat, 0.2 g saturated fat, 0 g trans fat, 20 mg cholesterol, 191 g carbohydrates, 60 g protein, 1560 mg sodium
DIETARY_SUPPLEMENTHigh fat meal
Meal containing 1030 calories, 62 g fat, 23 g saturated fat, 0.5 g trans fat, 445 mg cholesterol, 76 g carbohydrates, 41 g protein, 2080 mg sodium.
Sponsors
University of Guelph
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 50 Years
Healthy volunteers
Yes
Inclusion criteria
* 18 years or older * Healthy
Exclusion criteria
* History of smoking (tobacco or cannabis), defined as any smoking within the past 3 months * Diagnosed cardiovascular or metabolic disease(s) * Recent musculoskeletal injury handgrip exercise * Prescription of chronic medications other than oral contraceptives * History of hypertension or presence of arrhythmia
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Forearm blood flow | Baseline - Immediately before active and control interventions | Doppler ultrasound - tested at rest and during rhythmic handgrip exercise with and without lower body negative pressure |
| Forearm vascular conductance | Baseline - Immediately before active and control interventions | Blood flow divided by blood pressure - tested at rest and during rhythmic handgrip exercise with and without lower body negative pressure |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Blood pressure | Baseline - Immediately before active and control interventions | Finger plethysmography - tested at rest and during rhythmic handgrip exercise with and without lower body negative pressure |
| Heart rate | Baseline - Immediately before active and control interventions | ECG - tested at rest and during rhythmic handgrip exercise with and without lower body negative pressure |
Countries
Canada
Outcome results
None listed