A system, methods and apparatus for powered monofin that propels a swimmer through water uses one of two modes of power: 1. An electric-assist mode, in which the propulsor responds to a swimmer's kick by multiplying the work of the swimmer; 2. Inverse mode, in which the propulsor deactivates when the swimmer is working. In this mode, propulsion is inversely related to the work of the swimmer. As the swimmer does more work, power from the monofin is reduced, to a predetermined, average level of propulsion. As the swimmer does less work propulsion increases to the predetermined level.

Disclosed is a swimming assistance apparatus, which is worn on a user's both feet to provide the user with buoyancy, such that the user can float on water and swim in a good swimming style while repeatedly moving the waist from side to side like a fish, thereby reinforcing the user's waist muscles. Persons who have knee joint arthralgia or backache or persons who have disability in the lower body can use the swimming assistance apparatus for medical purposes, such as pain relief or treatment.

Disclosed is a swimming assistance apparatus, which is worn on a user's both feet to provide the user with buoyancy, such that the user can float on water and swim in a good swimming style while repeatedly moving the waist from side to side like a fish, thereby reinforcing the user's waist muscles. Persons who have knee joint arthralgia or backache or persons who have disability in the lower body can use the swimming assistance apparatus for medical purposes, such as pain relief or treatment.

A mono-fin for swim training is disclosed. The mono-fin has two separated boot structures that from two separate foot cavities for holding feet with toes positioned in front regions of each of the boot structures and heels positioned at back regions of each of the boot structures. The mono-fin has a mono-fin structure with blades portions connecting the boot structure through the front regions of each of the boot structures. In a middle region of the mono-fin structure and between the blade portions, there is flex region. The flex region allows angles between the boot structures, distances between the back regions of the boot structures and angles between the blade portions to be changed simultaneously by a swimmer while swim training in an aquatic environment.

A system, methods and apparatus for powered monofin that propels a swimmer through water uses one of two modes of power: 1. An electric-assist mode, in which the propulsor responds to a swimmer's kick by multiplying the work of the swimmer; 2. Inverse mode, in which the propulsor deactivates when the swimmer is working. In this mode, propulsion is inversely related to the work of the swimmer. As the swimmer does more work, power from the monofin is reduced, to a predetermined, average level of propulsion. As the swimmer does less work propulsion increases to the predetermined level.

A system, methods and apparatus for powered monofin that propels a swimmer through water uses one of two modes of power: 1. An electric-assist mode, in which the propulsor responds to a swimmer's kick by multiplying the work of the swimmer; 2. Inverse mode, in which the propulsor deactivates when the swimmer is working. In this mode, propulsion is inversely related to the work of the swimmer. As the swimmer does more work, power from the monofin is reduced, to a predetermined, average level of propulsion. As the swimmer does less work propulsion increases to the predetermined level.

Disclosed is a swimming assistance apparatus, which is worn on a user's both feet to provide the user with buoyancy, such that the user can float on water and swim in a good swimming style while repeatedly moving the waist from side to side like a fish, thereby reinforcing the user's waist muscles. Persons who have knee joint arthralgia or backache or persons who have disability in the lower body can use the swimming assistance apparatus for medical purposes, such as pain relief or treatment.

Disclosed is a swimming assistance apparatus, which is worn on a user's both feet to provide the user with buoyancy, such that the user can float on water and swim in a good swimming style while repeatedly moving the waist from side to side like a fish, thereby reinforcing the user's waist muscles. Persons who have knee joint arthralgia or backache or persons who have disability in the lower body can use the swimming assistance apparatus for medical purposes, such as pain relief or treatment.

Embodiments of water activity board 10 that may be configured with several components 210A-H to form a WABS 200, where the components 210A-H may be securely and removably coupled to the board 10 via one or more rail modules 100A-I. Other embodiments may be described and claimed.

Embodiments of water activity board 10 that may be configured with several components 210A-H to form a WABS 200, where the components 210A-H may be securely and removably coupled to the board 10 via one or more rail modules 100A-I. Other embodiments may be described and claimed.