HITFLOW: Acute Effects of High Intensity Training in Pregnancy on Fetal Well-being and Blood Flow Distribution

• Sponsor: Norwegian University of Science and Technology (Other)
• Overall Status: Recruiting
• CT.gov ID: NCT04288479
• Collaborator: St. Olavs Hospital (Other)
• Enrollment: 30
• Location: 1
• Arm: 1
• Anticipated Duration (Months): 15.2
• Patients Per Site Per Month: 2

Study Details

Study Description

Brief Summary

Pregnant women are recommended to be physically active ≥150 min/week, but <15% of Norwegian women attain this goal. Several well-designed studies on lifestyle interventions focusing primarily on exercise training in overweight/obese pregnant women have reported disappointing outcomes with regard to maternal glycemic control, gestational weight gain and infant outcomes. Low adherence to the training program was found to be a problem; the participants did not enjoy the exercise program and had difficulties scheduling time to exercise. Pregnant women also report that they are not sure what exercises are safe during pregnancy.

High intensity interval training (HIT), defined as short periods of intense activity separated by low-intensity breaks, has proved to induce superior improvements in insulin sensitivity and fitness compared with continuous moderate intensity training in individuals at increased risk for cardiometabolic diseases. Even short-term (6 weeks) HIT with brief (15-60 sec) work-bouts and a total time commitment of <45 min per week, improves insulin sensitivity similar to that attained after 6 months of traditional endurance training.

HIT is feasible and enjoyable for individuals with low fitness level and with obesity.

HIT is therefore a highly potent intervention that elicits important changes in a range of clinically relevant health outcomes in reproductive-aged women.

This study will investigate fetal responses to a single bout of HIT. Preliminary data of the investigators suggest that HIT does not negatively influence fetal heart rate. Others have reported that uterine and umbilical blood flow are not changed during or following acute exercise. However, no previous study has determined the acute effect of HIT on uterine blood flow and there are no studies investigating the fetal blood flow distribution in response to exercise. Since the relative distribution of blood to the fetal liver is associated with newborn adiposity, fetal blood flow distribution in response to exercise can provide insight about the effect of maternal exercise on offspring health.

Condition or Disease	Intervention/Treatment	Phase
Pregnancy	Behavioral: Single high-intensity interval training session	N/A

Study Design

• Study Type: Interventional
• Anticipated Enrollment: 30 participants
• Allocation: N/A
• Intervention Model: Single Group Assignment
• Intervention Model Description: before-after intervention effect measurementbefore-after intervention effect measurement
• Masking: None (Open Label)
• Primary Purpose: Treatment
• Official Title: Acute Effects of HIT on Fetal Well-being and Blood Flow Distribution - a Pilot Study
• Actual Study Start Date: Feb 23, 2022
• Anticipated Primary Completion Date: Jun 1, 2023
• Anticipated Study Completion Date: Jun 1, 2023

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Doing a single HIT session in gestational week 22-36	Behavioral: Single high-intensity interval training session; 10 minutes warming up at low-to-moderate intensity, 8x30 seconds high intensity interval training with fetal heart rate measurement after each 30 second work-bout, 2 minutes recovery at low-to-moderate intensity. Continuous monitoring of maternal heart rate.; Other Names: HIT

Outcome Measures

Primary Outcome Measures

1. blood flow in fetal veins [1 day]

   examined by Doppler ultrasound during 30 minutes

2. blood flow in fetal arteries [1 day]

   examined by Doppler ultrasound during 30 minutes

Secondary Outcome Measures

1. maternal heart rate [1 dag]

2. Fetal heart rate [1 day]

3. Umbilical vein diameter [1 day]

4. Maternal systolic blood pressure [1 day]

5. Maternal diastolic blood pressure [1 day]

6. Maternal body weight [1 day]

7. Maternal height [1 day]

Eligibility Criteria

Criteria

• Ages Eligible for Study: 18 Years and Older
• Sexes Eligible for Study: Female
• Accepts Healthy Volunteers: No

Inclusion Criteria:

• pregnant, gestational week 22-36

• singleton fetus

• no known diseases

• capable of cycling on an ergometer bike

Exclusion Criteria:

• hypertension

• gestational diabetes mellitus

• any contraindication to exercise training

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Dept Circulation and Medical Imaging, EXCAR Exercise Lab	Trondheim		Norway

Sponsors and Collaborators

• Norwegian University of Science and Technology
• St. Olavs Hospital

Investigators

• Study Director: Kjell Å Salvesen, md prof, St Olavs Hospital, Dept of Obstetrics and Gynecology
• Principal Investigator: Trine Moholdt, phd, Norwegian University of Science and Technology

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.

• Responsible Party: Norwegian University of Science and Technology
• ClinicalTrials.gov Identifier: NCT04288479
• Other Study ID Numbers: 62993
• First Posted: Feb 28, 2020
• Last Update Posted: Mar 10, 2022
• Last Verified: Feb 1, 2022

• Individual Participant Data (IPD) Sharing Statement: No
• Plan to Share IPD: No
• Studies a U.S. FDA-regulated Drug Product: No
• Studies a U.S. FDA-regulated Device Product: No
• Keywords provided by Norwegian University of Science and Technology: Exercise; High Intensity Interval Training; Pregnancy Outcome; Placental Circulation; Fetal Blood; Heart Rate, Fetal

Study Results

No Results Posted as of Mar 10, 2022