Balance Exercise Interventions in Parkinson's Disease: A Systematic Mapping Review of Components, Progression, and Intensity

Background: Rehabilitation in individuals with Parkinson’s disease (PD) often includes balance training, but knowledge about optimal training content remains limited.
Objectives: To describe the design, content, delivery, and reporting of balance training for individuals with PD, and furthermore, to map the systematic use and reporting of methods monitoring intensity in balance training
interventions for individuals with PD.
Methods: Six databases were searched. Interventions with at least 50 % of exercises challenging balance control were included. Balance training types (exergaming, multi-modal, sensory-motor integrated, and task-oriented)
were categorized based on specific balance exercise components: motor (limits of stability, anticipatory motor strategies, reactive motor strategies, and control of dynamics), sensory (vestibular, visual, and somatosensory systems), and cognitive (dual-tasking in motor or cognitive activities). Training Frequency, Intensity, Time, Type, Volume, and Progression (FITT-VP principles) were extracted.
Results: In total, 114 studies (interventions n = 126) with 5335 participants (mean age: 67.5 years; mean PD duration: 6.8 years) were included. The highest mean number of balance components was found in the multi-modal (5.8), followed by sensory-motor (5.6), task-oriented (4.2), and exergaming (4.0). Intensity strategies
were reported in 93 % of the exergaming interventions, which was superior to the other training types (multi-modal (18 %), sensory-motor (17 %), and task-oriented (6 %)).
Conclusions: Multi-modal and sensory-motor interventions had a greater focus on challenging balance components compared to other types of training, while exergaming interventions demonstrated superior reporting of intensity strategies. Future research is encouraged to prioritize implementing intensity strategies and aim to incorporate a broader range of balance components within balance training exercises.