In one aspect, a swimjet system may include a reverse thrust system worn by a swimmer proximate the frontal upper torso. The system provides a variable amount of reverse thrust such that the user can swim-in-place or make gradual forward progress. Importantly, this may enable a user to effectively extend a small residential pool to serve the same function as a twenty-five meter pool typically found at commercial or government facilities. The system also provides laminar current under the user while swimming, which solves the problems of leg drop, the need to out-kick the arm stroke, and turbulence and wave action around the head associated with conventional swim-in-place devices. Still further, in certain embodiments the system provides a relatively strong current in the region of the arm stroke moving away from the swimmer which provides enhanced resistance for proficient swimmers.

A hydrofoil simulator structure comprising a tank, in which a water current is generated, and a frame, which supports an elastic trampoline positioned above the water surface of the tank; the structure also comprising a series of elastic ropes associated with a trapeze harness worn by a user who stands on a board of a hydrofoil having wings immersed in water.

A liquid sealing actuator system enables use in anon-contact or low-friction manner. The system includes: an inner shaft having a first end; a hollow outer shaft having a first end that receives the first end of the inner shaft; at least one sealing ring positioned adjacent an internal surface of the hollow outer shaft, wherein the at least one sealing ring has an outer diameter that is less than an inner diameter of the outer shaft, thereby defining an annular seal gap; a mass attached to a distal end of either the inner shaft or the outer shaft; and a pressure source that injects a pressurised fluid into the hollow outer shaft, thereby applying a pressure against both the first end of the inner shaft and the at least one sealing ring that assists in lifting the mass; wherein the system is at least partially immersed in an external liquid such that the at least one sealing ring is submerged in the external liquid and a head of the external liquid above the at least one sealing ring defines a backpressure in the annular seal gap that opposes the pressure applied by the pressure source.

A wave-forming system includes a channel having a water inlet and a water outlet for directing water from the water inlet and the water outlet. The channel has a side wall and a bottom surface profile that slopes downward toward the water outlet and the side wall. The system also includes a back pressure barrier positioned in the water outlet to introduce a back pressure to the water flow inside the channel to continuously form waves across the channel.

A Exercise Pool is disclosed herein having a rigid frame modular in design to allow for improved delivery and assembling. As shown the system may be configured with a box like structure providing containment of the flow head and may be configured with a removable walk deck having an air gap built in. As disclosed the treadmill swimming pool system as its general configuration is safer for users as it inhibits and/or eliminates hair and body entrapment. As disclosed it has a balanced flow which better replicates or reproduces actual swimming conditions for an enhanced user experience. The propulsion system may be controlled with a variable frequency drive (VFD) to allow for improved swimming conditions and control of same.

A wave making apparatus for use with a wave pool having water is disclosed. The apparatus includes a wave making chamber having an interior and a plurality of chamber walls. The chamber also has a passageway connecting the interior to the wave pool and constructed to allow water to flow there between. A water vane is disposed of in or adjacent to the passageway. The wave vane includes at least one smooth and curved water vane wall, which in combination with the plurality of chamber walls, create at least two conduit paths for the water flowing between the interior to the wave pool. The conduit paths have two ends, and the water enters one end at a first direction and exits the second end at a second direction.

[Problem] To provide a foldable frame structure, unfoldable into a 2N-sided polygonal shape (N being an integer equal to or larger than 2), achieving a securely and rigidly supported unfolded state and a compact folded state. [Solving means] 2N upper rods (210), with an equal length, are coupled to each other to define a planer 2N-sided polygonal shape. First coupling means (220) coupling two adjacent upper rod (210) at a corresponding one of apices of the 2N-sided polygonal shape, and holding the two upper rod (210) in such a manner that the upper rod (210) are rotatable about an orthogonal axis orthogonal to axes of both of the two rods and rotation means (240) that enable each of the upper rods (210) to rotate about the axis (AX1) are provided. Folding to be a columnar shape as a whole can be achieved with the upper rods (210) pivoted about the orthogonal axis (AX2) to minimize an angle between two adjacent upper rods (210) while the upper rods (210) are rotated about the axis (AX1).

An improved swim spa is described which has a tank having a head end and a foot end filled with water. A forward current is created by pumping equipment which directs the forward current from a head end of the tank, past a swimmer in the water to a foot end of the tank. The pumping equipment may be attached to a removable wall insert to which may be removed to allow easy repair and maintenance. The forward current allows the swimmer to swim in place. The width of the forward current is chosen to be at least twice its depth. A diverter at the foot end of the tank has a curved surface for redirecting the forward current toward the sidewalls and then back toward the head wall in a horizontal plane and downward and back toward the head wall in a vertical plane.

It is disclosed a pump cell (25) for a surfing facility (10), wherein the pump cell (25) is configured to generate a, preferably laminar, layer-like water flow (20) for a surfable standing wave, wherein the pump cell (25) comprises: a pump (26), which is a radial pump (26) and has a preferably circular outlet opening; a diffusor (27) coupled to the pump (26) and being configured, to enlarge a cross-sectional area of the water flow (20) downstream of the pump (26) as far as an outlet opening (84) of the diffusor (27) and to reshape same into a wide and flat shape; and a pump frame (28), to which the pump (26) and the diffusor (27) are fastenable.

The present device relates to means for the individual training of highly-qualified athletes in cyclic sports. The technical result is the more reliable transfer of power from a drive to a working mechanism with the possibility of smoothing out ultrashort fluctuations (0.3-0.7 seconds) in force. The athlete training device comprises two spaced-apart bases, each having a pulley attached thereto for rotation in a single plane. An annular cable track is fastened between the pulleys, to which track a lanyard is secured by one end, the other end of the lanyard being fastened to a device for attaching the athlete. With the aid of a motor, a rotation rate is transmitted to one of the pulleys via a shaft. The shaft, which consists of a driving part and a driven part, has mounted thereon an adjustable transmission for controlling torque. The adjustable transmission is in the form of an electromagnetic powder clutch, consisting of a driving part, connected to the driving part of the shaft, and a driven part, connected to the driven part of the shaft. The driving and driven parts of the clutch are configured in the form of steel cylinders. An annular groove in the driven part contains an excitation winding, which is connected via slip rings and brushes to a dc power supply. The driven part of the clutch is mounted with clearance in a coaxial cavity in the driving part, the clearance gap between the driving part and the driven part of the clutch containing a ferromagnetic powder, the viscosity of which is adjusted by a clutch controller.