Interval Versus Continuous Exercise During Pregnancy

Effects of Acute High-intensity Intervals Versus Moderate-intensity Continuous Cycling on Maternal and Fetal Health

The objective of this randomized cross-over design was to investigate the fetal well-being and maternal glycemic response to an acute bout of aerobic high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) with pregnant individuals.

Study Overview

• Status: Completed
• Conditions: Pregnancy Related; Glucose, Low Blood; Fetal Heart Rate or Rhythm Abnormality Affecting Fetus; Fetal Blood Flow
• Intervention / Treatment: Other: High intensity Interval Training; Other: Moderate Intensity Continuous Training

• Study Type: Interventional
• Enrollment (Actual): 32
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • Alberta
    • Edmonton, Alberta, Canada, T6G 2R3
      • University of Alberta

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 50 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Female

Description

Inclusion Criteria:

• Carrying a singleton pregnancy (i.e. greater than or equal to 20 weeks of gestation).
• Has access to a stationary bike
• Located within Canada and/or within Edmonton Alberta

Exclusion Criteria:

• History of smoking within the last year
• Taking medications that may interfere with cardiovascular function.
• High-order pregnancies, e.g. twins or above.
• Females with absolute contraindications (as outlined by the Canadian Guidelines for Physical Activity throughout Pregnancy and the PARMed-X questionnaire)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: 1st Exercise session; Participants completed either the HIIT or MICT session.	Other: High intensity Interval Training; HIIT protocol consisted of 10 one-minute intervals of high-intensity work (i.e., > 90% HRmax) interspersed with nine one-minute intervals of self-paced active recovery (19-minutes total).; Other: Moderate Intensity Continuous Training; The MICT protocol consisted of 30-minutes of moderate intensity cycling (i.e., 64 - 76% HRmax).
Experimental: 2nd Exercise session; Participants completed the subsequent exercise protocol (i.e. HIIT or MICT)	Other: High intensity Interval Training; HIIT protocol consisted of 10 one-minute intervals of high-intensity work (i.e., > 90% HRmax) interspersed with nine one-minute intervals of self-paced active recovery (19-minutes total).; Other: Moderate Intensity Continuous Training; The MICT protocol consisted of 30-minutes of moderate intensity cycling (i.e., 64 - 76% HRmax).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Flash Glucose Monitor; interstitial Glucose	Measured by a Flash Glucose monitor inserted onto the back of the left tricep	7-days
Fetal Heart Rate	Measured via ultrasound pre and post exercise	3-minutes
Fetal Umbilical Blood Flow	Measured Via ultrasound pre and post exercise	3-minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
maternal outcomes- mode of delivery	Participants will provide the investigators with mode of delivery (vaginal or cesarean).	within one month postpartum
maternal outcomes- delivery complications	Participants will provide the investigators with information regarding any delivery complications.	within one month postpartum
maternal outcomes- pregnancy complications	Participants will provide the investigators with information regarding any pregnancy complications (gestational diabetes, pregnancy induced hypertension, preeclampsia).	any time during study
maternal outcomes- gestational weight gain	Participants will provide the investigators with the last maternal weight immediately before delivery. This will be used to calculate gestational weight gain (kg; last maternal weight - self reported pre-pregnancy weight).	within one month postpartum
Maternal Heart Rate	Measured via heart rate monitor; Measured prior to, during, and after exercise.	40-minutes
Accelerometer	The investigators will objectively measure physical activity using an accelerometer for one week. Average number of minutes per day spent in various activity levels will be determined.	7-days
Food Log	The investigators will objectively measure nutrients in diet using a seven day food record. This is completed through Food Prodigy/ Food Processor software.	7-days
Perceived rating of perceived exertion	Borg Scale; Ratings from 6 - 20; Rating of six is minimal perceived exertion and rating of 20 is maximal perceived exertion.	40-minutes
Cardiovascular fitness	Graded exercise test to volitional fatigue.	20-minutes
Cerebral Blood Flow of Posterior cerebral artery	Measured using a trans cranial doppler ultrasound. Measured prior to, during, and after exercise.	40-min
Sleep Quality	The investigators will objectively measure sleep quality using an accelerometer for one week. Average number of hours of sleep per night, time spent awake after sleep onset, and number of awakenings will be determined	7-days
Rating of Perceived Enjoyment (1-10 Scale)	Rating of 1 is the lowest level of perceived enjoyment, rating of 10 is maximal perceived enjoyment	40-minutes
Blood pressure	Measured with a finometer; Measured prior to, during, and after exercise.	40-min
Cardiac Output	Measured with a finometer; Measured prior to, during, and after exercise.	40-min
Cerebral blood flow of middle cerebral artery	Measured using a trans cranial doppler ultrasound. Measured prior to, during, and after exercise.	40-minutes
fasted blood sample- sex hormones	Fasted blood samples (~30ml) will be analyzed for sex hormones (estrogen, progesterone, testosterone).	5-minutes
Physical Activity Questionnaire	The participants will report physical activity using the pregnancy physical activity questionnaire (gives metabolic equivalent hours per week (MET-hr/week).	5-minutes
Depression rating	Participants will answer a 10-question questionnaire regarding their mood. A score of 10 or higher is indicative of depressive symptoms. The investigators will report the over number of women in each group who have a score of 10+ at the start and end of the intervention.	5-minutes
Respiratory measures - respiratory frequency	Breathing frequency (breaths per minute). Measured using spirometry.	40-minutes
Respiratory measures - tidal volume	Tidal Volume (Liters per breath). Measured using spirometry.	40-minutes
Respiratory measures - oxygen	Oxygen metabolism (% oxygen used per breath). Measured using a gas analyzer.	40-minutes
Respiratory measures - carbon dioxide	Carbon Dioxide production (% carbon dioxide per breath). Measured using a gas analyzer.	40-minutes
Respiratory measures - lung volume	Total Lung Capacity (Liters). Measured using spirometry.	40-minutes
Fetal Outcome - birth weight	Participants will provide the investigators with birth weight for the infant (grams)	within one month postpartum
fetal outcomes- length	Participants will provide the investigators with birth length for the infant (cm)	within one month postpartum
fetal outcomes- gestational age	Participants will provide the investigators with gestational age at delivery (weeks)	within one month postpartum
fetal outcomes- NICU	Participants will provide the investigators with information regarding length (days) of admission to Neonatal Intensive Care Unit (NICU) if applicable	within one month postpartum

Collaborators and Investigators

• Sponsor: University of Alberta
• Investigators: Principal Investigator: Margie H Davenport, PhD, University of Alberta

Study record dates

Study Major Dates

• Study Start (Actual): December 1, 2020
• Primary Completion (Actual): December 30, 2022
• Study Completion (Actual): December 30, 2022

Study Registration Dates

• First Submitted: March 28, 2022
• First Submitted That Met QC Criteria: May 5, 2022
• First Posted (Actual): May 11, 2022

Study Record Updates

• Last Update Posted (Actual): January 20, 2023
• Last Update Submitted That Met QC Criteria: January 18, 2023
• Last Verified: October 1, 2022

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Congenital Abnormalities
• Other Study ID Numbers: Pro00103630

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No