Figure 1.
Flexion on the voice condition (A) and extension on the voice condition (B).
In the flexion-on-the-voice condition, participants flexed their hip, knee, and ankle joints in line with a vocalization (A). In the extension-on-the-voice condition, participants extended their joints in line with a vocalization (B).
Figure 2.
Knee movement trajectory and voice time on the phase plane.
Knee movement trajectory on the phase plane (A). The phase angle is expressed as the difference from the peak knee position. In the flexion-on-the-voice condition, difference between voice time and the peak knee-flexion point is calculated (B), and in the extension-on-the-voice condition, difference between voice time and the peak knee-extension point is calculated (C).
Figure 3.
Mean voice frequency (A) and SD of voice frequency (B).
Vertical bars represent between-subjects standard deviations.
Figure 4.
Typical examples of the phase angle of voice time for one participant.
The value at the top of each trajectory is the average voice frequency in each trial. In the extension-on-the-voice condition (B), the replacement of joint extension on the voice by joint flexion on the voice occurred at 180 bpm. This replacement did not occur in the flexion-on-the-voice condition.
Figure 5.
Phase angle of voice time (A) and SD of phase angle (B).
Vertical bars represent between-subjects standard deviations.
Figure 6.
Vertical bars represent between-subjects standard deviations.