Relearning physiological movement patterns is a key factor to success in the treatment of functional deficits. Motivation to train sustainably is essential for successful motor re-education and can be promoted by instrumentally supported real-time feedback. Study findings should improve the understanding of real-time feedback visualization for exercises targeting the lower extremities. A mixed-methods survey on recognition, comprehensibility, color scheme and shape of six real-time feedback prototype visualizations was conducted among three user groups (physicians, physiotherapists, and patients). The mean correct recognition of body regions visualized in the feedback was 55 %, ranging from 29 % to 74 %. Comprehensibility, color scheme and shape were best received for feedback with clear visual guidance, sympathetic and motivating color schemes and abstract visualizations of body regions. Insights were gathered for the design, optimization, and customization of visualizations to develop a real-time feedback prototype.