An abdominal strengthening apparatus is an apparatus to allow a user to perform core abdominal muscle exercises from a seated position. The abdominal strengthening apparatus includes a stationary base, a tilting arm, a supporting member, a handlebar, and a foot-supporting bar. The tilting arm is pivotably mounted to the stationary base. The supporting member is pivotably mounted to the tilting arm. The foot-supporting bar supports the user's feet and is positioned opposite to the supporting member. The handlebar is adjacently connected to the supporting member opposite to the tilting arm. In implementation, the user grasps the handlebar and exerts the user's body weight onto the handlebar. The force on the handlebar forces the supporting member downward to lever the foot-supporting bar. Therefore, the user engages the user's core muscles through use of the user's body weight to strengthen the user's core muscles.

A foldable treadmill having a base and a rotational shaft whose two ends are fixed with supporting posts respectively; handle bars are mounted to top ends of the supporting posts respectively; two seats are fixed on the rotational shaft and correspond to the support posts; one end of each wire is connected with a corresponding handle bar, another end of each wire is connected with a corresponding pin; rotation of the handle bars to achieve folding of the treadmill drives the wires to pull the pins; each seat has a position limiting hole which a corresponding pin is removably inserted, so that the two seats together with the rotational shaft achieve a fixed state or a rotatable state with respect to the base.

The invention discloses a multifunctional sliding storage treadmill, comprising the frame and the armrest. The frame comprises the fixed frame and the sliding frame, and there is a traction mechanism provided between them. The tensioning mechanism is provided at the bottom of the sliding frame, and the traction mechanism comprises the first motor, the transmission belt, the guide pulley, the first traction block, the connecting rod, and the second traction block. The first motor, transmission belt, guide pulley, and the first traction block are installed in the fixed frame, and the second traction block is movable installed in the sliding frame. The invention has the advantage of easy storage and good stability of the device, which solves the problems of inconvenient storage operation, cumbersome operation and affecting storage efficiency, and poor stability at the connection of the folding running joint in the prior art folding treadmills.