Table 2.

Maximum wrapping contact forces for different cases at various levels (N)

Vertebra level	0 N		180 N
	Stoop	Squat	Stoop	Squat
T12	0	0	0	0
L1	40	27	60	32
L2	55	39	113	66
L3	62	43	97	44
L4	80	55	168	89
L5	99	70	251	138

Maximum wrapping contact forces occur nearly at the time of maximum trunk flexion