Exercise Timing on the Morning Blood Pressure Surge

University of Guelph

Status: Completed

Conditions: High-intensity Interval Exercise; Ambulatory Blood Pressure Monitoring; Post-Exercise Hypotension

Treatments: Other: Evening high-intensity interval exercise; Other: Morning high-intensity interval exercise

Study type: Interventional

Funder types: Other

Identifiers

NCT06702930

19-07-002

Details and patient eligibility

About

The goal of this clinical trial was to assess the effects of morning vs. evening high-intensity interval exercise on the magnitude of the morning blood pressure surge in young healthy adults. The main questions it aimed to answer were:

• Does the timing of high-intensity interval exercise modulate the magnitude of the morning blood pressure surge?
• Do sex differences exist?

Participants came in and completed a bout of high-intensity interval exercise in the morning (8-10 am) and evening (5-7 pm) as well as a no exercise control, and ambulatory blood pressure was assessed for 24 hours afterwards.

Full description

Introductory Visit:

Participants came in for 4 visits. The first visit was an introductory visit where chronotype, eligibility for exercise, and anthropometrics were measured. This was followed by a maximal incremental exercise test to determine aerobic capacity (i.e., V̇O2peak) on a cycle ergometer, and instrumentation of an ambulatory blood pressure monitor for familiarization during daily activities and sleep.

Intervention Visits:

Three intervention visits (control, morning exercise, and evening exercise) were completed. The order was randomized using and each visit was separated by a minimum of 36 hours. Each intervention visit began by obtaining the participant's resting blood pressure and heart rate and ended with the instrumentation of the ambulatory blood pressure monitor. No exercise was performed during the control visit. The morning exercise visit included a bout of high-intensity interval exercise between 8-10 am and the evening exercise visit included a bout of high-intensity interval exercise between 5-7 pm. The high-intensity interval exercise protocol consisted of a light intensity, 3-minute warm-up at 15% peak power followed by ten 1-minute work intervals at 80% of peak power, with each interval separated by 1-minute rest intervals at 15% peak power. A 3-minute cool down was performed at 15% peak power.

Enrollment: 31 patients

Sex: All

Ages: 18 to 50 years old

Volunteers: Accepts Healthy Volunteers

Inclusion and exclusion criteria

Inclusion:

• Between 18-50 years of age.
• No history of known disease.
• None smokers.
• No use of chronic medications other than oral contraceptives.

Exclusion:

• <18 years of age.
• >50 years of age.
• Cardiovascular disease.
• Metabolic disease.
• History of smoking (within the past 3 months).
• Chronic medications (other than oral contraceptives).

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: None (Open label)

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31 participants in 3 patient groups

Control

No Intervention group

Description:

No exercise was performed and ambulatory blood pressure was assessed for 24 hours.

Morning high-intensity interval exercise

Experimental group

Description:

High-intensity interval exercise was performed between 8-10 am and ambulatory blood pressure was assessed for 24 hours after.

Treatment:

Other: Morning high-intensity interval exercise

Evening high-intensity interval exercise

Experimental group

Description:

High-intensity interval exercise was performed between 5-7 pm and ambulatory blood pressure was assessed for 24 hours after.

Treatment:

Other: Evening high-intensity interval exercise