Abstract: The lifting capacity of a human subject is assessed through dynamic testing protocols utilizing a cylindrical robot that tracks the path of the lift and provides load position information to a data analysis system. The movable linkage of the cylindrical robot moves in a very low friction manner and is designed to be extremely lightweight, while having remarkable strength and rigidity to withstand bending moments and torsional effects. Thus, the apparatus permits three-dimensional lift testing of actual loads, including actual job loads, with the test subject experiencing the true feel and inertial effects of the load. Static force transducers and related means are provided to permit isometric testing.

Abstract: A back exercise machine having a neck exercise attachment which allows movement about three machine axes corresponding to the cervical axes of flexion/extension, lateral flexion and rotation. Selective resistance to movement about each axes may be provided and torque, position and velocity measurements made with respect to neck movement performance against the resistance.

Abstract: A knee exercise apparatus which provides for movement about three axes which correspond to and are coaxial with the knee joint axes of flexion/extension, tibial rotation and abduction/adduction. A specific arrangement for independently measuring torque and concomitant angular position changes about the knee joint axis of flexion/extension and tibial rotation as well as angular position changes about the axis of abduction/adduction is shown and described as are associated restraints to minimize superfluous movement about joints adjacent to the knee joint of interest.

Abstract: An improved hydraulic valve system particularly adapted for use in a hydraulic circuit of an exercise apparatus in order to more quickly equalize the high and low pressure sides of the hydraulic circuit when a load is removed therefrom. The valve system is adapted to allow the high pressure side after the force has ceased to open a relief valve so as to allow the low pressure side and the reservoir to quickly come into equilibrium with the high pressure side. In this fashion, the tendency of the base line pressure to be elevated during repetitive exercises is obviated and accurate exercise data can be accumulated.

Abstract: An improved pelvic restraint is provided for use in association with an exercise apparatus which is most suitably a low back exercise apparatus. The pelvic restraint comprises a seat having laterally adjustable hip restraints provided with a belt for extending therebetween across the abdomen of a user. An adjustable back restraint is also provided for engagement with the lower back. In this fashion, the pelvic restraint prevents lifting or lateral shifting of the hips and forward or rearward pitching of the pelvic area so that more accurate evaluation may be conducted on an exercise apparatus to which the pelvic restraint is secured.

Abstract: An improved thoracic restraint device is provided for use in association with a low back exercise machine adapted for evaluating low back exercise movement against a resistance, particularly rotational movement of the lower back. The restraint comprises a back support having a pair of horizontally extending arms and a pair of flexible restraint straps adapted to be secured across the thorax of the user to the arms so as to secure the thorax of the user against the back support. In order to further limit rotational movement of the thorax during low back exercise, an adjustable back stabilizer is provided beneath the back support and adapted to restrainingly engage the lower thoracic area of the back so as to minimize rotation of the thoracic vertabrae during low back exercise.

Abstract: A exercise apparatus for measuring performance of the ankle joint and subtalar joint of a user including a first hydraulic rotary actuator cooperatively associated with the ankle joint and having a rotational axis colinear with the pivotal axis of the ankle joint and a second hydraulic rotary actuator cooperatively associated with the subtalar joint and having a rotational axis colinear with the pivotal axis of the subtalar joint. A seat and a plurality of restraints are utilized in order to restrict motion about adjacent joints of a user and to facilitate alignment of the aforementioned axes of the joints of interest with the axes of the two hydraulic rotary actuators utilized by the apparatus.

Abstract: An ankle exerciser (10) is disclosed for permitting isokinetic exercise of the ankle joint of the user. The foot of the user is secured to a foot plate (54) by a strap (124). The foot plate is capable of motion about three mutually perpendicular axes (X--X, Y--Y, Z--Z), with one axis corresponding to the axis of pivotal motion of the ankle joint in dorsel and plantar flexion. The motion about each axis is restricted by a double acting fluid cylinder (64, 82, 104). Individual metering valves (160, 162, 164) are provided for restricting flow between the chambers of the cylinders and a reservoir (152) to selectively determine the desired resistance to motion. Pressure gauges (154, 156, 158) are associated with each of the fluid cylinders to indicate the force exerted by the user resisted by the particular fluid cylinder. In a second embodiment, an ankle exerciser (250) is provided for exercising both ankles of the user. The foot plates (282, 284) are provided with straps to secure the feet of the user thereon.