Table 1.
Mean ± standard deviation of muscle activity amplitude (%MAXIMUM) according to the height of the support base (floor and elevated platform), vision (open and closed), and postural adjustment conditions.
| Height | Vision | Postural Adjustment | AD | LE | RA | RF | BF | TA | GL |
|---|---|---|---|---|---|---|---|---|---|
| Floor | Open eyes | APA (n = 80) | 56.0 ± 21.8 | 35.0 ± 10.8 | 15.6 ± 6.6 | 47.7 ± 11.4 | 52.5 ± 16.7 | 1.7 ± 1.2 | 35.5 ± 29.7 |
| OPA * (n = 80) | 66.4 ± 18.1 | 73.6 ± 15.6 | 71.4 ± 8.3 | 65.9 ± 8.1 | 66.8 ± 11.6 | 78.3 ± 9.8 | 73.4 ± 12.6 | ||
| CPA (n = 80) | 48.3 ± 15.4 | 57.2 ± 15.5 | 62.1 ± 10.1 | 55.5 ± 10.6 | 56.7 ± 16.7 | 47.0 ± 10.9 | 46.4 ± 10.7 | ||
| Closed eyes | APA (n = 80) | 63.6 ± 31.3 | 35.1 ± 11.0 | 15.2 ± 8.0 | 54.4 ± 45.8 | 54.6 ± 14.9 | 1.7 ± 1.1 | 30.9 ± 27.4 | |
| OPA * (n = 80) | 66.7 ± 19.3 | 73.6 ± 15.6 | 70.2 ± 7.4 | 67.3 ± 10.3 | 65.0 ± 11.7 | 76.4 ± 11.0 | 70.8 ± 11.0 | ||
| CPA * (n = 80) | 46.3 ± 16.7 | 59.2 ± 16.6 | 62.3 ± 8.8 | 54.8 ± 11.2 | 53.5 ± 14.3 | 46.5 ± 12.6 | 48.2 ± 12.0 | ||
| Elevated platform | Open eyes | APA (n = 80) | 51.2 ± 18.0 | 35.2 ± 9.3 | 19.8 ± 9.5 | 49.9 ± 11.5 | 54.1 ± 15.4 | 1.8 ± 1.2 | 29.8 ± 25.2 |
| OPA * (n = 80) | 65.3 ± 15.7 | 66.5 ± 8.8 | 70.1 ± 9.4 | 63.5 ± 8.5 | 66.6 ± 10.8 | 76.4 ± 10.8 | 84.9 ± 21.1 | ||
| CPA (n = 80) | 52.5 ± 13.5 | 57.8 ± 12.3 | 59.5 ± 9.3 | 55.6 ± 11.1 | 56.3 ± 14.2 | 50.3 ± 12.4 | 47.4 ± 10.1 | ||
| Closed eyes | APA (n = 80) | 52.4 ± 28.2 | 35.0 ± 8.7 | 17.8 ± 7.6 | 51.3 ± 12.3 | 54.2 ± 16.6 | 2.4 ± 2.3 | 29.4 ± 25.4 | |
| OPA * (n = 80) | 67.2 ± 14.6 | 71.2 ± 12.2 | 72.3 ± 8.5 | 67.2 ± 15.6 | 66.9 ± 12.5 | 77.9 ± 10.5 | 73.2 ± 13.4 | ||
| CPA (n = 80) | 52.1 ± 17.0 | 60.1 ± 15.0 | 61.7 ± 8.2 | 57.1 ± 11.1 | 55.2 ± 13.4 | 47.9 ± 12.0 | 51.1 ± 10.9 |
Anterior deltoid AD, lumbar extensor LE, rectus abdominis RA, rectus femoris RF, biceps femoris BF, tibialis anterior TA, gastrocnemius lateralis GL, anticipatory postural adjustment, APA; online postural adjustment, OPA; compensatory postural adjustment, CPA). OPA * indicates that muscle activity was the highest during OPA compared with APA and CPA (p < 0.0001).