Exercise Timing on the Morning Blood Pressure Surge

Not Applicable

Completed

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

• Registration Number: NCT06702930
• Lead Sponsor: University of Guelph

Brief Summary

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.

Detailed 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.

Study Timeline

• Study Start: 2020-01-28
• Primary Completion: 2023-06-08
• Study Completion: 2023-06-08
• Status Verified: 2024-11
• Study First Submitted: 2024-11-19
• Study First Submitted QC: 2024-11-21
• Last Update Submitted: 2024-11-24
• Study First Posted: 2024-11-25
• Last Update Posted: 2024-11-27

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 31

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Primary Outcome Measures

Name	Time	Method
Morning blood pressure surge	Through study completion, an average of 4 weeks.	The difference between morning blood pressure (the mean of the 4 blood pressure readings after awakening) and sleep-trough blood pressure (the mean of the lowest blood pressure during sleep and two adjacent blood pressure readings).

Secondary Outcome Measures

Name	Time	Method
Nighttime blood pressure dip	Through study completion, an average of 4 weeks.	The percent difference between daytime blood pressure (average of all blood pressure readings when participants reported being awake) and nighttime blood pressure (average of all blood pressure readings when the participant reported being asleep).

Trial Locations

Locations (1)

University of Guelph; 🇨🇦 Guelph, Ontario, Canada