FitMum: Fitness for Good Health of Mother and Child

Physical activity level from randomization to GA week 28+0-6 determined by a wrist-worn activity tracker, Garmin Vivosport, with built-in heart rate monitor and accelerometer. The activity tracker is to be worn continuously by the women from inclusion until delivery. After inclusion baseline physical activity level will be measured for one week, followed by randomization to one of the three study groups and continuous monitoring of physical activity level by the activity tracker. Preferably, the activity tracker is also worn continuously from delivery and one year ahead. The activity tracker determines the frequency, duration and intensity of activity periods on a minute-to-minute basis and data from the activity tracker is wirelessly synced to its associated smartphone application, Garmin Connect, and research platform, Fitabase.

Weight gain during pregnancy

A Danish version of the validated 'Pregnancy Physical Activity Questionnaire' (PPAQ-DK) will be used to subjectively measure physical activity level during pregnancy.

The doubly labeled water technique will be used to measure free-living energy expenditure at GA week 28+0-6.

The activity tracker will also be used to measure physical activity level of the mother during the entire pregnancy period, meaning after GA week 28+0-6 until delivery as well.

The activity tracker will also be used to measure physical activity level of the mother one year after delivery.

Clinical pregnancy, delivery and neonatal outcomes will be collected from medical records. E.g. incidence of Gestational Diabetes Mellitus, gestational age at delivery, mode of delivery, induction of labor, epidural, 5-minute Apgar score, pH of umbilical cord and birth weight.

Maternal body composition will be assessed by doubly labeled water during pregnancy.

Maternal body composition will be assessed by DXA scanning after delivery.

Health-related quality of life and function will be determined by a Danish version of the questionnaire "Medical Outcomes Study Short Form 36" (SF-36).

Sick leave and pelvic and low back pain will be assessed by a questionnaire verbally administered at interviews at visits.

Sleep quantity and quality will be assessed continuously by the activity tracker.

Sleep quantity and quality will be assessed by a Danish version of the questionnaire "Pittsburgh Sleep Quality Index" (PSQI).

Plasma metabolites and hormones (e.g. triglyceride, HDL, LDL, total cholesterol and HbA1C) will be assessed by analysing maternal blood and umbilical cord blood.

Epigenetic profiles will be assessed by analysing DNA methylation in maternal blood, paternal blood and umbilical cord blood.

Placental function will be assessed via analyses of placental samples, maternal blood and umbilical cord blood.

Investigations of personal understandings of physical activity in everyday life of pregnant women and social, structural and cultural practices and factors influencing successful implementation of exercise during pregnancy will be based on semi-structured qualitative interviews

Investigations of personal understandings of physical activity in everyday life of pregnant women and social, structural and cultural practices and factors influencing successful implementation of exercise during pregnancy. Data will be collected by observations

Investigations of personal understandings of physical activity in everyday life of pregnant women and social, structural and cultural practices and factors influencing successful implementation of exercise during pregnancy. Data will be collected by auto-documentation.

Mixed methods will be used to do a qualitative and quantitative process evaluation. Data for the process evaluation are based on semi-structured qualitative interviews and administratively collected process data (e.g. frequency of training and counseling sessions, visits and measurements), electronic case report form files, and activity logs.

Self-efficacy for physical activity will be measured by a Danish version of the American questionnaire "Pregnancy Exercise Self-efficacy Scale" (P-ESES-DK).

Motivation for physical activity will be measured by a Danish version of the British questionnaire "Behavioral Regulation Exercise Questionnaire" (BREQ-2).

Growth in the offspring will be assessed by questionnaires, using data from visits to the participants' general practitioners.

Physical psycho-motor development in the offspring will be assessed using a Danish version of the questionnaires Ages and Stages 3 (ASQ-3) for 12- and 14 month old babies.

Physical activity level one year after due date, determined by a wrist-worn accelerometer, Actigraph GT3X+. The activity tracker is to be worn continuously by offspring for 7 days. Data is stored in the device and transferred to the researchers' computer.

Mental well-being in mothers and fathers post partum will be assessed using a Danish validated screening-tool for parental post-partum depression, primarily based on the Edinburgh Postnatal Depression Scale and selected questions from The Masculine Depression Scale.

validation of activity trackers for measuring sleep will be conducted using polysomnography (PSG) in a sub-group of forty women already participating in FitMum RCT. The women will wear the PGS for one night.

Breastmilk for metabolomics and lipidomics analyses is obtained from one single feed 7-14 days after delivery.