| Popis: |
The effect of music loudness on human movement vigor in walking, running and some exercise and sports domain activities has been sparsely studied. The few prior studies employed varied experimental conditions and sometimes with mixed results. Although the isochronous beat of a metronome might also be considered music in its simplest form, no previous studies have reported the effect of metronome sound intensity on vigor in physical activities. Employing a single-case experimental design, this study examined the effects of sound intensity on stepping vigor for both music and metronome auditory stimuli. Experimental conditions included stepping to a single tempo of 116 BPM during synchronous walking around a 2-mi greenway loop track. With walking synchrony confirmed at 100% and lap distance a constant, lap speeds for each stimulus-intensity condition were determined from lap times with high precision. Randomized data were collected over a six-month period with six repetitions for each stimulus-intensity pair.For music, intensity level was varied for three different playlists of familiar/enjoyable music at three normal listening levels of 69.3, 75.0, and 80.2 dB (± 0.6 dB at each level). Over this relatively narrow intensity range of 11 dB, step length and commensurate walking speed increased 3.7% - 5.7% (ANOVA pooled p < 0.0001 for each playlist). The speed-dB response for the music composite was approximately linear over the range, and the music was strongly activating (more step-length and proportional speed) relative to a no sound (no stimulus) condition at the same regression tempo/cadence.For metronome, 5 different levels of sound intensity were employed over a range of 58.9 – 82.0 dB (± max of 0.5 dB at each level). An unexpected increase in speed of 12.2% was obtained over the 23 dB range (ANOVA pooled p < 0.0001). The speed-dB response was linear (R2 = 0.993). As expected, vigor response was greater for music than for metronome at equivalent intensity levels. However, another unexpected finding for metronome was that at higher intensity levels the metronome stimulus was activating, and at lower levels it was relaxing relative to the no sound condition at the same regression tempo/cadence. The increase in speed per unit increase in dB for metronome (0.53% / dB) was surprisingly greater than for music (0.34 – 0.52 % / dB). This might be attributed to a higher beat salience for metronome.Within the conditions and parameters of this study, these findings clearly showed a positive effect of sound intensity on vigor response for both music and metronome during synchronous walking. The findings have performance implications for walkers and perhaps for runners and in some other rhythmic physical activities. The findings may also contribute to a further understanding of the human auditory sensorimotor function and for intervention in some human gait disorders. |
