Background: Borderline personality disorder (BPD) is one of the most common personality
disorders, with a lifetime prevalence of up to 5.9% and core symptoms of emotional and
behavioral dysregulation, instability in interpersonal relationships, identity
disturbances, stress-related dissociation, non-suicidal self-injuries, and suicidal
behavior. Treatment mainly consists of psychotherapeutic procedures, frequently
supplemented by pharmacotherapy to reduce specific symptoms such as affective and
cognitive dysregulation. Besides possible adverse effects from medication, both,
psychotherapy and medication do not lead to a complete remission of BPD. Previous studies
point towards a positive influence of physical exercise on BPD symptoms and related
neurobiological processes, while to our knowledge no study has investigated the effects
of exercise in patients with BPD yet.
Objectives: To investigate the effects of a single session of physical exercise on stress
regulation, cognitive and emotional functioning, and associated neurophysiological
processes in patients with borderline personality disorder. A further aim is to identify
the optimal exercise intensity (moderate vs. high intensity).
Hypotheses: The investigatiors expect that acute exercise will enhance stress perception
and cognitive and emotional functioning, which will be reflected in enhanced behavioral
measures and changes on biomarker level. In addition, the investigatiors expect to gather
insights regarding the optimal exercise intensity.
Methods: 60 patients with borderline personality disorder and 60 healthy controls will
participate in two 30-min experimental conditions on separate days in counterbalanced
order (at least 48 hours apart): in the exercise condition, half of the group will cycle
on an ergometer with moderate intensity, the other half will perform a high-intensity
interval training. Intensities will be calculated based on the individual maximal heart
rate measured during a maximal exercise test in a pre-experimental session. In the
control condition, all participants will watch a movie. Before and after each condition,
they will perform a classic and an emotional version of the Stroop test, in order to
assess exercise effects on impulsivity and emotion regulation. To test for exercise
effects on stress-related responses, they will further participate in a Stress test 90
min following each condition. The investigatiors will collect saliva and blood samples
together with state questionnaires at various study time points to test for effects on
peripheral biomarkers related to stress, cognition, and BPD pathology (e.g., cortisol,
alpha-amylase, serotonin metabolism, noradrenaline, BDNF).
