Table 3.
Crank Position (in Degrees) for the Onset, Offset, and Duration of Muscle Activity (Mean±Standard Deviation)a
| Muscle | Onset | Offset | Duration | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| TD Group at Cadence of 30 rpm | CP Group at Cadence of 30 rpm | TD Group at Cadence of 60 rpm | CP Group at Cadence of 60 rpm | TD Group at Cadence of 30 rpm | CP Group at Cadence of 30 rpm | TD Group at Cadence of 60 rpm | CP Group at Cadence of 60 rpm | TD Group at Cadence of 30 rpm | CP Group at Cadence of 30 rpm | TD Group at Cadence of 60 rpm | CP Group at Cadence of 60 rpm | |
| Left gluteus maximus | 292.0±27.0 | 6.6±27.2 | 257.1±29.5 | 206.1±86.3 | 307.3±28.1 | 9.4±33.2 | 302.9±28.7 | 324.3±100.1 | 15.4±3.6 | 210.2±183.0 | 33.0±19.6 | 179.9±131.6 |
| Left biceps femoris | 326.6±66.7 | 240.9±45.3 | 227.1±68.5 | 54.4±67.4 | 47.4±62.6 | 352.9±73.6 | 33.8±78.3 | 12.9±48.3 | 123.1±103.6 | 138.6±82.0 | 194.8±90.7 | 298.9±59.2 |
| Left rectus femoris | 153.4±25.2 | 21.0±40.0 | 131.4±40.4 | 344.6±44.8 | 239.5±47.7 | 292.7±62.1 | 231.4±43.6 | 297.2±63.6 | 84.4±54.8 | 220.8±114.9 | 105.5±70.7 | 270.5±120.5 |
| Left vastus lateralis | 157.6±37.9 | 27.6±84.2 | 147.0±31.7 | 26.4±115.7 | 244.7±28.1 | 341.7±75.1 | 253.7±43.4 | 345.3±48.9 | 87.4±47.8 | 231.0±122.5 | 108.2±62.7 | 308.5±68.3 |
| Left medial hamstrings | 290.2±29.9 | 255.5±36.2 | 268.5±39.0 | 180.5±52.9 | 106.7±52.4 | 40.8±50.8 | 96.6±50.3 | 33.9±55.8 | 170.6±63.8 | 148.3±60.6 | 187.3±70.1 | 275.5±103.0 |
| Left anterior tibialis | 104.2±81.9 | 22.1±87.1 | 99.0±89.5 | 5.7±69.8 | 199.5±53.7 | 357.9±74.0 | 198.8±82.7 | 2.5±52.1 | 94.5±78.8 | 274.5±110.2 | 109.7±78.3 | 342.2±33.2 |
| Left lateral gastrocnemius | 312.3±82.3 | 242.7±92.5 | 213.6±59.0 | 3.4±75.9 | 13.9±51.7 | 70.6±83.7 | 90.1±67.4 | 6.6±64.0 | 136.2±110.6 | 225.5±106.3 | 254.6±76.4 | 342.3±33.4 |
| Left soleus | 230.2±84.4 | 184.7±30.4 | 191.1±49.7 | 80.7±58.9 | 0.4±46.4 | 46.9±73.9 | 48.5±51.7 | 40.3±42.5 | 185.6±109.7 | 206.9±84.3 | 230.5±54.7 | 319.4±41.7 |
a
Zero degrees is the point at which the left crank arm was horizontal and farthest from the subject, as shown in Figure 1. Interaction effects of group and cadence were seen for the duration for the left biceps femoris muscle, the left medial hamstring muscle, and the left soleus muscle. Significance defined as P<.0031 due to 16 muscles being studied overall. Light gray=difference between groups, black=difference between cadences, dark gray=difference between groups and between cadences. CP=cerebral palsy, TD=typical development.