A waist training device includes unit members of arc shaped and adapted to be assembled as a ring. The inner diameter of the ring is determined by the number of the unit members. Each unit member defines a passage, and the passages of the unit members are connected with each other to form a rail extended annularly along the ring. For each member, a pair of pivot shafts is located at one end of the passage, and a pair of pivot holes is located at the other end of the passage. The pivot shafts of each unit member are pivotally assembled with the pivot holes of an adjacent unit member. A counter weight member is assembled in the rail. The counter weight member has a seat connected to a counter weight block. The counter weight member moves along the rail by the sliding of the seat in the rail.

Disclosed herein is a device which detects repetitive movement of a user's body part. The device has a sensor which detects G forces along at least two axes when the user repeatedly moves the body part; a memory, which stores reference data corresponding to ideal reference data; a processor/computing unit, which communicates with the sensor and the memory, and receives data associated with the G forces. The processing/computing unit compares the ideal reference data with the data associated with the detected G forces. A feedback component is connected to the processor/computing unit to provide the user with a signal when a target has been achieved. Also disclosed is a method of computing data received by the device and an exerciser device that simulates the movement of a hula hoop.

Disclosed herein is a device which detects repetitive movement of a user's body part. The device has a sensor which detects G forces along at least two axes when the user repeatedly moves the body part; a memory, which stores reference data corresponding to ideal reference data; a processor/computing unit, which communicates with the sensor and the memory, and receives data associated with the G forces. The processing/computing unit compares the ideal reference data with the data associated with the detected G forces. A feedback component is connected to the processor/computing unit to provide the user with a signal when a target has been achieved. Also disclosed is a method of computing data received by the device and an exerciser device that simulates the movement of a hula hoop.

An improved apparatus for physiotherapy includes a lever arm. A biasing device pivotally biases the lever arm about a pivot axis. There is a support configured for supporting the lever arm above an exercise equipment. A harness is configurable on a torso of a user to couple the user to the lever arm. The pivot axis corresponds to an anatomical longitudinal axis of the user and the torso of the user is biased by the lever arm about the anatomical longitudinal axis.