None listed
Conditions
Brief summary
In this study we will be looking at the effects of vigorous intensity exercise during each trimester of pregnancy on blood pressure and blood vessels, as well as foetal heart rate. More specifically we want to see if exercising at a higher intensity may be more beneficial to vascular function during pregnancy. During pregnancy adaptations occur to the circulatory system to support the growing foetus. Sometimes these changes can result in negative health outcomes for the mother and the baby, e.g. gestational hypertension and pre-eclampsia. Exercise during pregnancy has been shown to have a range of benefits, including reducing blood pressure and the risk of pre-eclampsia. Higher intensity exercise has been shown to have more benefits on blood pressure in non-pregnant populations, however research on the effects during pregnancy is currently lacking.
Interventions
Eligible participants will provide informed consent prior to taking part in the exercise sessions. Women can be recruited from 10 weeks of gestation, with the exercise trials to take place up until 36 weeks of gestation.
The participants will be required to attend three exercise sessions weekly at the exercise clinic for the duration of their pregnancy. They will also be asked to complete a questionnaire prior to the first session to gain characteristics of the included populations so that thi
Eligible participants will provide informed consent prior to taking part in the exercise sessions. Women can be recruited from 10 weeks of gestation, with the exercise trials to take place up until 36 weeks of gestation. The participants will be required to attend three exercise sessions weekly at the exercise clinic for the duration of their pregnancy. They will also be asked to complete a questionnaire prior to the first session to gain characteristics of the included populations so that this data can be used as cofactors in the statistical analysis. Participants will be asked to complete a 24-hour food diary prior to the first session. They will then be asked to avoid high sodium foods in the 24 hours prior to each session. The participants will be provided with a list of high sodium foods to avoid. The three exercise sessions at will be conducted by Accredited Exercise Physiologists with at least one year experience. Participants will report to the clinic in a fed state following 48 hours of no strenuous physical activity, having consumed no caffeine on the day of testing. The initial session will involve a submaximal graded exercise test. The following submaximal treadmill protocol will be adhered to: Submaximal familiarisation test – Cornell Protocol - Submaximal test performed on the treadmill. - Measures will include: Arterial stiffness (AS) (resting), heart rate (HR) (every minute), BP (every stage), MAP (every stage), RPE (Borg 6-20 scale) (every minute), predicted Vo2 max (calculated using HR) - Subjects will be familiarised with the equipment (treadmill, SphygmoCor, sphygmomanometer, HR monitor, RPE scale) - Tests will be terminated once subjects reach 85% of age predicted HRmax. American College of Sports Medicine (ACSM) equations will be used to calculate the estimated aerobic capacity (Vo2 = 0.1(speed)+1.8(speed)(fractional grade)+3.5). Cornell treadmill protocol Stage - minute - speed km/h - Gradient % 1 - 2 - 2.74 - 0 2 - 4 - 2.74 - 5 3 - 6 - 2.74 - 10 4 - 8 - 3.38 - 11 5 - 10 - 4.02 - 12 6 - 12 - 4.82 - 13 7 - 14 - 5.47 - 14 8 - 16 - 6.11 - 15 9 - 18 - 6.76 - 16 10 - 20 - 7.4 - 17 11 - 22 - 8.05 - 18 The three exercise sessions will be as follows: Session 1: 30-35 minute light intensity reformer Pilates session (8-10 RPE, 45-60% age predicted heart rate max (PHRmax)) This session will consist of low impact exercises performed on a reformer with a specific focus on core, pelvic floor and the deep hip stabilising muscles. The exercises involved will be modified when necessary to accommodate the physical changes that occur during pregnancy. Session 2: Moderate intensity resistance training (RPE 11-13, 55-70% PHRmax) This session will involve low impact resistance training exercise performed with bodyweight, resistance bands, free weights and machine weights. All major muscle groups of the body will be targeted. The exercises involved will be modified when necessary to accommodate the physical changes that occur during pregnancy. Session 3: Vigorous intensity interval training VIIT 4x4 protocol The vigorous intensity interval session will consist of a light 5 min warm up and cool down on a treadmill (9-11 RPE, 45-60% PHRmax). The participants will then perform four, four-minute intervals of vigorous intensity walking (RPE 14-16, 70-85% HRmax) interspersed with four, three-minute intervals of moderate intensity walking (RPE 11-13, ~65% HRmax). Treadmill walking will be used for this session. All exercise sessions will be performed individually under constant supervision of the exercise physiologist.
Sponsors
Courtney Giles
Study design
Allocation
Non-randomised trial
Intervention model
Crossover
Primary purpose
Prevention
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
18 Years to 40 Years
Healthy volunteers
No
Inclusion criteria
Pregnant women less than 30 weeks gestation, willing to visit the exercise clinic 3 times per week for exercise sessions.
Exclusion criteria
Diagnosed gestational health conditions that are considered absolute contraindications to exercise: Ruptured membranes, premature labour Persistent second or third trimester bleeding/placenta previa Pregnancy-induced hypertension or pre-eclampsia Incompetent cervix Evidence of intrauterine growth restriction High-order pregnancy (e.g., triplets) Uncontrolled Type I diabetes, hypertension or thyroid disease, other serious cardiovascular, respiratory or systemic disorder
Outcome results
None listed