Abdominal exercise apparatus

1. An exercise apparatus for performing an abdominal exercise by a user having a lower back and a trunk having a trunk axis, the apparatus comprising:

a frame,

a seat having a seating surface and a pelvic stabilization pad having a lower back engagement surface mounted to the frame, and

an input arm assembly interconnected by a first interconnection to a first resistance mechanism and by a second interconnection to a second resistance mechanism,

the input arm assembly including a manually graspable mechanism and being arranged on the apparatus such that the input arm assembly is pivotable beginning from a start motionless position along a path of travel forwardly away from the pelvic stabilization pad under resistance exerted by the first resistance mechanism,

the seating surface and the pelvic stabilization pad being mounted, adapted and arranged on the frame in a disposition relative to each other such that the user is positioned in a disposition that enables the user to simultaneously sit on the seating surface, engage the user's lower back against the lower back engagement surface, manually engage the manually graspable mechanism and push the input arm assembly forwardly using or exercising the user's abdominal muscles to exert forwardly directed force against the resistances exerted by the first and second resistance mechanisms;

wherein the first resistance mechanism is adapted to increase the resistance as the degree of pivoting of the input arm assembly increases along the path of travel away from the start motionless position and forwardly away from the pelvic stabilization pad.

2. The exercise apparatus of claim 1 wherein the trunk has a trunk weight, the trunk weight of the user's trunk increasing opposition to the resistance force on pushing the input arm assembly forwardly.

3. The apparatus of claim 1 wherein the user's trunk has a trunk axis and the seat and the pelvic stabilization pad are arranged on the apparatus such that when the user is seated on the seat with the user's lower back engaged against the lower back engaging surface and the input arm assembly is disposed in the start motionless position, the user's trunk axis is disposed in a generally vertical disposition and at a forward angle relative to vertical leaning away from the pelvic stabilization pad when the user pushes the input arm assembly forwardly.

4. The apparatus of claim 3 wherein the seat and the pelvic stabilization pad are arranged on the apparatus such that when the user manually engages and pushes the input arm assembly from the start motionless forwardly away from the pelvic stabilization pad, the user's trunk axis pivots forwardly away from the pelvic stabilization pad and travels from the generally vertical disposition toward a forwardly angled disposition, the user's lower back being opposed by less force from the trunk weight and more resistance from the first resistance mechanism as the user's trunk axis is pivoted toward a more forwardly angled disposition.

5. An exercise apparatus for performing an abdominal exercise by a user having a lower back and a trunk having a trunk axis, the apparatus comprising:

a frame,

a seat having a seating surface and a pelvic stabilization pad having a lower back engagement surface mounted to the frame, and

an input arm assembly interconnected by a first interconnection to a first resistance mechanism and by a second interconnection to a second resistance mechanism,

the input arm assembly including a manually graspable mechanism and being arranged on the apparatus such that the input arm assembly is pivotable beginning from a start motionless position along a path of travel forwardly away from the pelvic stabilization pad under resistance exerted by the first resistance mechanism,

the seating surface and the pelvic stabilization pad being mounted, adapted and arranged on the frame in a disposition relative to each other such that the user is positioned in a disposition that enables the user to simultaneously sit on the seating surface, engage the user's lower back against the lower back engagement surface, manually engage the manually graspable mechanism and push the input arm assembly forwardly using or exercising the user's abdominal muscles to exert forwardly directed force against the resistances exerted by the first and second resistance mechanisms;

wherein the first resistance mechanism comprises either (a) an extendable spring that increases in resistance as the spring is increasingly extended, the spring being interconnected to the input arm assembly in an arrangement such that movement of the input arm assembly along the path of travel toward the pelvic stabilization pad increasingly extends the spring and movement toward the start motionless position reduces extension of the spring or (b) an enclosed cylinder having a piston slidably mounted within the cylinder forming opposing fluid sealed chambers within the piston, the piston being interconnected to a rod that extends outside the enclosed cylinder for driving the piston, the chambers containing a selected compressible fluid, the rod being interconnected to the input arm assembly and driven by movement of the input arm assembly from the start motionless position toward the pelvic stabilization pad to cause fluid in at least one of the chambers to compress and increase resistance against movement of the input arm assembly with an increase in the degree of compression of the fluid.

6. An exercise apparatus for performing an abdominal exercise by a user having a lower back and a trunk having a trunk axis, the apparatus comprising:

a frame,

a seat having a seating surface and a pelvic stabilization pad having a lower back engagement surface mounted to the frame, and

an input arm assembly interconnected by a first interconnection to a first resistance mechanism and by a second interconnection to a second resistance mechanism,

the input arm assembly including a manually graspable mechanism and being arranged on the apparatus such that the input arm assembly is pivotable beginning from a start motionless position along a path of travel forwardly away from the pelvic stabilization pad under resistance exerted by the first resistance mechanism,

the seating surface and the pelvic stabilization pad being mounted, adapted and arranged on the frame in a disposition relative to each other such that the user is positioned in a disposition that enables the user to simultaneously sit on the seating surface, engage the user's lower back against the lower back engagement surface, manually engage the manually graspable mechanism and push the input arm assembly forwardly using or exercising the user's abdominal muscles to exert forwardly directed force against the resistances exerted by the first and second resistance mechanisms;

wherein the seating surface is generally disposed in a plane disposed at a downwardly sloping angle relative to horizontal, the seat having a downwardly disposed front end and an upwardly disposed rear end, the pelvic stabilization pad being mounted such that the lower back engagement surface is disposed at the upwardly disposed rear end of the seating surface in an arrangement that engages the user's lower back when the user is seated on the seating surface and pushing the user's lower back toward the pelvic stabilization pad with the user's legs.

7. The exercise apparatus of claim 6 wherein the apparatus includes a foot pad mounted forwardly relative to the seat, the foot pad being arranged on the apparatus such that the user can engage the foot pad with the user's foot and push on the foot pad with the user's leg to push the user's lower back into engagement with the lower back engagement surface while seated on the seat.

8. An exercise apparatus for performing an abdominal exercise by a user having a lower back and a trunk having a trunk axis, the apparatus comprising:

a frame,

a seat having a seating surface and a pelvic stabilization pad having a lower back engagement surface mounted to the frame, and

an input arm assembly interconnected by a first interconnection to a first resistance mechanism and by a second interconnection to a second resistance mechanism,

the input arm assembly including a manually graspable mechanism and being arranged on the apparatus such that the input arm assembly is pivotable beginning from a start motionless position along a path of travel forwardly away from the pelvic stabilization pad under resistance exerted by the first resistance mechanism,

the seating surface and the pelvic stabilization pad being mounted, adapted and arranged on the frame in a disposition relative to each other such that the user is positioned in a disposition that enables the user to simultaneously sit on the seating surface, engage the user's lower back against the lower back engagement surface, manually engage the manually graspable mechanism and push the input arm assembly forwardly using or exercising the user's abdominal muscles to exert forwardly directed force against the resistances exerted by the first and second resistance mechanisms;

wherein the lower back engagement surface is generally circular in radial cross-section.

9. A method of performing a back extension exercise by a user having a lower back and a trunk having a trunk axis, using an apparatus comprising:

a frame,

a seat having a seating surface and a pelvic stabilization pad having a lower back engagement surface mounted to the frame, and

an input arm assembly interconnected by a first interconnection to a first resistance mechanism and by a second interconnection to a second resistance mechanism,

the input arm assembly including a manually graspable mechanism and being arranged on the apparatus such that the input arm assembly is pivotable beginning from a start motionless position along a path of travel forwardly away from the pelvic stabilization pad under resistance exerted by the first resistance mechanism,

the seating surface and the pelvic stabilization pad being mounted, adapted and arranged on the frame in a disposition relative to each other such that the user is positioned in a disposition that enables the user to simultaneously sit on the seating surface, engage the user's lower back against the lower back engagement surface, manually engage the manually graspable mechanism and push the input arm assembly forwardly using or exercising the user's abdominal muscles to exert forwardly directed force against the resistances exerted by the first and second resistance mechanisms;

the method comprising the user's:

seating the user's trunk on top of the seat when in the start motionless position,

pushing the user's lower back into engagement against the lower back engaging surface while seated on the seat,

manually engaging the manually graspable mechanism, and

pivoting the user's trunk forwardly using or exercising the user's abdominal muscles to exert forwardly directed force against the resistances such that the user's trunk axis is disposed at a forward angle sufficient to push the input arm assembly from the start motionless position forwardly away from the pelvic stabilization pad.