Fig 1. Study design.

Participants were randomized into one of two groups: discrete visual biofeedback or discrete auditory biofeedback. The white boxes indicate five test sessions, and black boxes indicate two training sessions. The participants performed four test sessions: pre-1 and post-1 on the first day (Day 1), pre-2 and post-2 on the second day (Day 2), and retention on the fourth day after training (Day 4) without augmented sensory biofeedback. The training sessions consisted of 8 blocks with augmented sensory biofeedback. One block consisted of 5 trials, and each trial (seven cycles) had a duration of 35 seconds. BF, augmented sensory biofeedback.