A machine for exercising or testing the lumbar muscles of the human body. The machine has a movement arm pivotable about a horizontal axis through forces exerted by said muscles while the subject is seated with his pelvis restrained against movement and with his back engaging a resistance pad. The rear of the pelvis engages a pelvic pad which is movable to detect any unwanted movement of the pelvis during the exercise. The resistance pad is movable relative to the movement arm to enable measurement of the effective lever arm of the moment applied to the movement arm by the subject. On one side of the movement arm is a mechanism for connecting the movement arm to a weight stack to impose a predetermined yieldable resistance to the movement arm. On the other side of the movement arm is an adjustable counterweight mechanism which may be releasably connected to the movement arm to counterbalance the subject's torso mass.

A spring loop folding sunshield and method of manufacture in which a spring loop is enclosed within tape across the intermediate portion of the sunshield and around the edges of the sunshield. The tape is attached across the intermediate portion of the sunshield by creating two ridges across the intermediate portion of the sunshield and sewing or otherwise attaching a tape over the ridges. In one method of creating the ridges, the material is cut into two approximate halves, leaving an intermediate portion which is then sewn to the two approximate halves to create the ridges across the intermediate portion of the sunshield.

A load applying driving apparatus for an exercise device of any kind includes a motor providing a counterforce, a crank mechanism operatively connected to the motor and a flexible transmission member for transmitting the counterforce from the motor via the crank mechanism to a user-actuated member of the exercise device. Upon exercise, the motor exerts a load on the user-acutated member when the user carries out the lifting stroke and the return stroke.

A weight lifting exercise apparatus capable of multiple maximum and minimum segments of resistance force is provided. The apparatus disclosed includes a free-standing support frame within which a weight support carriage having detachable weight members is supported for vertical movement. A shaft is rotatably mounted on the frame and an exercise bearing member which may be engaged by a user is secured to the shaft as well as a cable wheel having a circular arc segment. A length of cable is secured at one end to the weight support carriage, reeved through cable guides and attached at its other end to the cable wheel. A fixed support disk is secured to the shaft and a first rotatable disk which supports a first torque arm is rotatably mounted on the shaft. The first torque arm supports a moveable weight and the first disk may be variably attached to the fixed disk. A second torque arm is also rotatably supported by the shaft, supports a second weight member and may be secured to the first disk. Because the initial positions of the first and second torque arms and weight members may be variably preselected, a myriad of resistance force patterns are available.

Method and apparatus for exercising or testing the rotary torso muscles in which the chest and shoulder area of the subject is secured against movement while the pelvis is also secured against movement to isolate the rotary torso muscles for testing or exercise. The subject while so secured and seated exerts a force with the rotary torso muscles to rotate a movement arm about a vertical axis against a resistance suitably chosen from a weight stack to be less than the maximum static strength of said muscles. The subject then returns to the starting position and repeats the exercise until the rotary torso muscles can no longer rotate the movement arm. The subject's static strength is measured by fixing the movement arm in several different angular positions and measuring the force exerted by said muscles on the movement arm in each of said positions.