TABLE 1. Average height changes pre- and posthyperextension.

Sec	Prehyperextension	Posthyperextension
0	0	+5.234 (1798)mm
20	-1.226 (0.831) mm	-1.873 (1.194) mm
40	-1.883 (1.172) mm	-2.617 (1.729) mm
60	-2.272 (1.260) mm	-3.277 (2.208) mm
80	-2.549 (1.298) mm	-3.774 (2.715) mm
100	-2.905 (1.407) mm	-4.130 (2.890) mm
120	-3.206 (1.515) mm	-4.466 (3.050) mm
140	-3.370 (1.516) mm	-4.781 (3.220) mm
160	-3.681 (1.792) mm	-5.066 (3.258) mm
180	-3.868 (1.894) mm	-5.253 (3.359) mm
200	-4.141 (1.917) mm	-5.479 (3.455) mm
220	-4.275 (1.982) mm	-5.636 (3.493) mm
240	-4.440 (1.986) mm	-5.866 (3.551) mm
260	-4.562 (2.010) mm	-6.023 (3.613) mm
280	-4.838 (2.165) mm	-6.198 (3.665) mm
300	-5.030 (2.266)mm	-6.374 ( 3.766) mm