Institute of Sports Science

PhD network „Individual response to physical activity – A transdisciplinary approach"

Background

In everyday life, we consider individual differences in appearance, attitudes, lifestyle etc. as normal. In health-related activity programs, in contrast, people are often treated in a stereotypical way and do not get individually tailored behavioral advice. In recent years, there has been an increasing number of studies on both physiological and affective responses to physical activity stimuli showing considerable differences between individuals.

What has not been thoroughly analyzed by now is how the subjectively experienced individuality of a person (represented in the person’s biography and body-related self-concept) and the individual physiological stress response to a standardized exercise training session influence the adaptive response to exercise regimes. How physiological and affective responses to physical activity interrelate with each other has also been barely investigated.

The main goal of our PhD network is to examine how individuals react affectively and physiologically to physical activity interventions dependent on their health- and activity-related biographical experiences, their relationship to their own body, and their motivation to exercise.

This is highly relevant because interventions which claim to effectively and sustainably promote the individual’s health have to take into account that not every form of physical activity leads to the same responses in different individuals. Likewise, not every activity is equally rewarding for a person, not least due to his or her activity- and health-related biographical experiences and motivational prerequisites. In this regard, the expected results of the PhD network contribute to the advancement of personalized health promotion and prevention strategies using one of the most effective means – physical activity.

In our study, all participants will take part in two different endurance training programs (moderate-continuous-intensity vs. high-intensity-intervals). Each training program lasts 6 weeks with three training sessions per week.

At the beginning of the study and after each training block questionnaires and further diagnostic tools will be used to measure biopsychosocial adaptions. The whole study runs for a total of 15 weeks.

Subprojects

The research project consists of five PhD projects that focus on individual biographies, body image, motivation and affective responses, physiology and prevention, and epigenetics.

Biography

Research Question

Individual life courses and biographies determine our everyday behavior. If we are, for example, pursuing an active or rather an inactive lifestyle largely depends on the experiences we have made in our individual life worlds, as well as in specific activity-settings. Our aim is to analyze how patterns of health- and activity-related behaviors develop, manifest, and change over the life course. Interdisciplinarily, we aim to analyze, how biographical experiences relate to physiological and psychosocial outcomes of exercise.

Methods

For our research, we use biographical mappings at the beginning of the study. This software-based method takes approximately 60 to 90 minutes and allows for a visual reconstruction of the individual life course and biography. During and after the training intervention, biographical experiences, which are made in the training setting are reconstructed, as well. Additionally, we use questionnaires related to subjective well-being and further biopsychosocial health dimensions.

Body image

Research Question

Body image is one of the fundamental components of our sense of self. It is crucial to the formation and maintenance of both our mental and physical wellbeing. The influence of an individual’s body image could motivate or impede engagement in physical activity. Physically active individuals report a more positive attitudinal body image. At the same time, one’s motivation to initiate and maintain physical activity might be to influence disturbed body image in a positive manner. There is little evidence on individuals’ responsiveness to physical activity with respect to body image. As such, this bi-directional relation between body image and physical activity remains poorly understood.

The main goal of the current study is to investigate body image and its dynamic changes following the uptake of regular physical activity on a longitudinal basis. The study also aims to investigate the extent to which the individual’s body image is related to affective and biological adaptation reactions to physical training.

Methods

In cooperation with the Max Planck Institute for Intelligent Systems, Tübingen, we are able to utilise new and innovative methods towards measuring dynamic changes in body image: the 4D body scanning technology, as well as editable biometric 3D body avatar. The 4D Dynamic Scanner captures full body shape at high spatial as well as temporal resolution, allowing us to study body shape both in its static and dynamic configuration. The 3D body avatar tool is a statistical body model, which was generated from the alignment of 2000+ body scans. We have adapted the task in such a way that participants are able to create realistic body variations quickly and simply on the computer screen. We then combine the acquisition of subjective body perception (through the 3D body avatar task) with objective data of one's own body (using the 4D body scans). In this way, we can dynamically analyse interactions between participants’ actual and perceived bodies. In addition, standardised questionnaires assessing self-esteem, body dissatisfaction and body image related behaviour are implemented. Interoceptive awareness, as well as accuracy, are also tested throughout.

Motivation and affective responses

Research Question

Motivation for and affective responses to physical activity differ across individuals. However, it is unclear how affective responses are associated with physical responses in various forms of physical exercise and to what extent motivational aspects have a moderating influence in this context. Across projects, another aim of the study is to investigate the relationship between the affective response to physical activity, the individual biography, and the individual body image.

Methods

The methods of the study include both a paper-and-pencil survey and interviews via tablets during physical activity using validated testing procedures. Thereby, psychological preconditions, responses, and consequences with respect to different exercise modalities can be assessed.  Additionally, accelerometry is used to gather objective data on the extent of physical activity on a daily basis. For that purpose, participants wear activity sensors, which gives us information about their habitual physical activity behavior in everyday life.

Physiology and prevention

Research Question

It has become evident throughout the years that physical inactivity leads to an increased risk of mortality as well as significant cardiovascular morbidity, such as diabetes and cardiovascular disease. Therefore, the implementation of an individualized exercise prescription plays a crucial role in comprehensive cardiovascular care. In this context, the individual response of physical fitness and disease-related factors (e.g., cardiometabolic risk) to exercise training varies highly. Yet, it is unclear whether health-related improvements are mainly due to individual factors or are the result of a specific dose of exercise. On an interdisciplinary level we analyze how physiological responses relate to health- and activity-related biographies, the body image, and affective and epigenetic responses.

Methods

The present investigation aims to obtain valid instruments which allow a prediction and optimization of the dose-response relationship of exercise training, and therefore to improve individual training counselling in the preventive and therapeutic setting. Moreover, we aim to investigate whether the physiological response depends on the type of exercise (moderate-intensity continuous training versus aerobic interval training), and whether there are gender-specific adaptations.

Epigenetics

Research Question

The term “epigenetics” describes molecular mechanisms, such as alterations at specific proteins that lead to a stronger or weaker expression of specific genes. Epigenetic mechanisms help to adapt the genetic information saved in our DNA to environmental circumstances without altering the genetic information itself. In this project, we are analyzing the question how individual physiological adaptation reactions correlate with epigenetic characteristics. Furthermore, across projects, we aim to analyze if there are correlations between physiological training adaptation, biographical and emotional characteristics and epigenetic changes.

Methods

Specifically, our project aims to investigate the question whether in the model system “skeletal muscle tissue”, specific epigenetic markers can be determined that allow to predict an individual’s response to a specific exercise stimulus. After sampling tissue specimens, a broad variety of these markers will be analyzed before and directly after a single bout of exercise, as well as after a longer period of training. Subsequently, the data will be correlated with those of the other subprojects. By this means, we plan to determine a panel of markers, one of them being epigenetic characteristics in skeletal muscle, that helps to predict an individual’s reaction to a specific training stimulus and eventually leads to the development of individualized training regimens.