ActiLup: is it feasible? High-intensity interval training in systemic lupus erythematosus patients with fatigue: protocol for a prospective, monocentric proof-of-concept study.

The symptoms of active systemic lupus erythematosus (SLE) potentially lead to inactivity, muscle loss and social isolation. In addition to medical treatment, the current EULAR recommendations describe the relevance of physical activity, exercise and training as a non-pharmacological management option in patients with SLE. A positive interaction between fatigue and the basic health-promoting effects of exercise is well established. Still unclear is what kind of training, setting, and intensity show optimal objective and subjective outcomes. The study will include 40 adult SLE patients with moderate to severe fatigue. The study lasts 28 weeks and is divided into a 12-week "real-world" monitoring phase before rehabilitation, a 4-week inpatient rehabilitation phase, and a 12-week maintenance activity and training phase after the rehabilitation. The parameters consisted of physical performance parameters, laboratory parameters, physician and patient-related questionnaires and activity data based on a fitness watch. During rehabilitation, patients receive individual high-intensity interval training (HIIT), basic endurance training and functional interval training. This proof-of-concept trial aims to investigate if high-intensity interval training is feasible and how VO2peak is increased. Additionally, the effect of the severity of fatigue measured by patient-related outcomes and the number of anti-NR2 antibodies is focussed. This study was approved by the Ethics Committee of the Medical Association of Rhineland-Palatinate and complies with the standards of the Declaration of Helsinki. All participants will sign a written informed consent. Trial registration number: DRKS00022933.