Fit for Two - A Pilot Study on Physical Activity Levels During Pregnancy
Conditions: Physical Activity, Well-being
Sponsor: University Medicine Greifswald

 
 
 
 
 
 
 
 
 
 
Fit for Two – Pilot study on physical activity during 
pregnancy 
 
Fit4Two 
 
Study protocol 
 
 
 
 
 
 
 
 
 
 
Number of the Ethical Approval: BB002/20 
AUGUST 10, 2020 
 
 

2 
 
 
1. Background 
More than two thirds (81.6 %, 87.7%) of German women in childbearing age (18–29, 30-39 
don’t meet the recommendations of 150 minutes of moderate‐intensity physical activity 
weekly (Krug S et al., 2013). For healthy pregnant women, the guidelines of the American 
College of Obstetrician and Gynecologists recommend to be physically active of moderate-
intensity level at least 150 minutes per week. Despite the known benefits of physical activity, 
studies have shown that the majority of pregnant women do not engage in regular physical 
activity. Moreover, fewer than 15% of pregnant women achieve the recommended levels of 
physical activity (Pearce et al, 2013). Therefore, more research is needed aiming to increase 
pregnant women’s physical activity level. 
2. Objectives 
The primary aim of the study is to examine extent and intensity levels of physical activity in 
different periods (trimesters) of pregnancy. Secondary outcomes are (1) parameters of 
cardia ultrasound examination (Left ventricular mass index [LVMI], Global longitudinal strain 
[GLS], Ratio of maximum early and late diastolic flow velocity of mitral valve [E/ A], 
Deceleration time [DT] and Isovolumetric relaxation time of the left ventricle [IVRT]), (2) 
Well-beeing, and (3) Strength of the mother-child-bond. 
3. Methods/ Study design 
The study region is Greifswald, a city with approximately 58.000 inhabitants in Northeast of 
Germany. Fit4two is a prospective study consisting of up to three measurement periods of 
physical activity via accelerometry, up to three self-administered surveys as well as up to three 
cardia ultra sound examinations and one follow-up assessment 12 weeks after the 
(anticipated) delivery. The flow chart of the study design is depicted in figure 1. 

3 
 
 
Figure 1 Flow chart 
Study population 
The study population consists of pregnant women who meet the following inclusion criteria: 
1. Current pregnancy ≤ 23 weeks, 
2. Sufficient language skills, and 
3. No seriously cognitive impairments 
Recruitment 
Pregnant women will be recruited in the following ways: 
1. Advertisement in local newspapers and social media (e.g. facebook) 
2. Distribution of leaflets in all gynecological practices of the city 
3. Distribution of leaflets in nurseries and public institutions (supermarket, restaurants) 
Potential participants contact the study staff by telephone or E-mail. A short telephone 
screening is performed to assess the inclusion criteria. For women who meet the inclusion 
criteria, an appointment for the first visit at the examination center of the German Centre for 
Cardiovascular Research (DZHK) Greifswald is made. 
First visit (Trimester 1, week 9-12 or Trimester 2, week 23-26) 
 Women are informed (face-to face and by leaflet) about the study. Written informed 
consent will be obtained. Upon consent, women receive an acclereometer (ActiGraph 
GT 3X®, ActiGraph, Pensacola, FL, USA). The validated three-axis device captures and 

4 
 
records physical activity and sedentary time. Data will be recorded at a sampling 
frequency of 30 Hz. Participants are instructed to wear the accelerometer during a 
period of seven days on the right hip at daytime and to remove it for water-based 
activities (e.g., swimming). The second visit will be scheduled. 
Second visit 
 The accelerometer will be collected from the participant. Women were asked to fill in a 
self-administrative paper-pencil questionnaire. Thereafter, a cardiac ultrasound 
examination will be conducted. Thereafter the third visit will be scheduled. 
Third visit (Trimester 2, week 23-26 or Trimester 3, week 36-39) 
 Again, women receive an acclereometer. They are instructed to wear the accelerometer 
during a period of seven days on the right hip at daytime and to remove it for water-
based activities (e.g., swimming). An appointment for the fourth visit will be made. 
Fourth visit 
 The accelerometer will be collected from the participant. Women were asked to fill in a 
self-administrative paper-pencil questionnaire to assess. Thereafter, a cardiac 
ultrasound examination will be conducted. The collection of data (acclerometer, 
questionnaires, cardiac ultrasound examinations) has been completed for women who 
entered the study in trimester 2. An appointment for the fifth visit will be made with 
women, who entered the study in the first trimester of their pregnancy. 
Fifth visit (Trimester 3, week 36-39) 
 Again, women receive the acclereometer. They are instructed to wear the device during 
a period of seven days on the right hip at daytime and to remove it for water-based 
activities (e.g., swimming). An appointment for the last visit will be made. 
Sixth visit (Trimester 3, week 36-39) 
 The accelerometer will be collected from the participant. Women were asked to fill in a 
self-administrative paper-pencil questionnaire. Thereafter, a cardiac ultrasound 
examination will be conducted. The collection of data (acclerometer, questionnaire, 
cardiac ultrasound examination) has been completed now. 
 
 

5 
 
Documentation, data storage, and data security 
All participants receive a study ID at the first visit in the examination center to ensure their 
correct assignment over time. Data from the accelerometer, data from the self-administered 
questionnaire and data from the cardiac ultrasound examination will be stored in a central 
data base. Personal data (name, address, telephone number) will not be entered in the data 
base. The data storage is managed according to the standards for data security and data 
privacy. Only the staff member of the project team have access to personal data during the 
study.  
Data analysis 
ActiLife software (version 6.13.2 or later, ActiGraph,Pensacola, FL, USA) will be used for data 
download and data processing. A valid measurement is defined as a record, of ≥ 10 h wearing 
time per day, and a record time of ≥ 5 days. In a first step, accelerometer based data (light 
physical activity, moderate- to vigorous physical activity, and sedentary time) will be 
descriptively analyzed. Subsequently, associations between patterns of physical activity/ 
sedentary time and (1) measures from cardia ultrasound examination, (2) well-beeing, and (3) 
mother-child bond will be analyzed. The software package STATA (version 15.1) will be used.