Clinical trial NCT06702930: Exercise Timing on the Morning Blood Pressure Surge
Official title: The Effects of Morning vs. Evening High-intensity Interval Exercise on the Magnitude of the Morning Blood Pressure Surge
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Post-Exercise Hypotension
Ambulatory Blood Pressure Monitoring
High-intensity Interval Exercise
Keywords: Ambulatory blood pressure monitoring
Morning blood pressure surge
High-intensity interval exercise
Post-exercise hypotension
Lead sponsor: University of Guelph
Sponsor class: OTHER
First posted: 2024-11-25
Enrollment: 31
Sex: ALL
Minimum age (years): 18
Maximum age (years): 50
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: PREVENTION

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.

Eligibility 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).

Primary outcomes:
measure: Morning blood pressure surge
timeFrame: Through study completion, an average of 4 weeks.
Secondary outcomes:
measure: Nighttime blood pressure dip
timeFrame: Through study completion, an average of 4 weeks.
Other outcomes:
Locations:
city: Guelph
country: Canada
facility: University of Guelph
state: Ontario
Study officials:
affiliation: University of Guelph
name: Julian Bommarito, MSc
role: STUDY_DIRECTOR
affiliation: University of Guelph
name: Philip Millar, PhD
role: PRINCIPAL_INVESTIGATOR
References: