Constant weight bi-fins

Constant Weight Bi-Fins

Constant Weight Bi-Fins (CWTB) is a discipline in the sport of freediving, where an athlete descends and ascends using a pair of bi-fins without any change in weight during the dive. This discipline is recognized by major freediving organizations such as AIDA International and CMAS.

History

The discipline of Constant Weight Bi-Fins has evolved from the broader category of constant weight freediving, which traditionally included both monofins and bi-fins. The distinction of bi-fins as a separate category was made to acknowledge the different techniques and skills required compared to using a monofin.

Equipment

The primary equipment used in Constant Weight Bi-Fins includes:

• Bi-Fins: A pair of fins, one for each foot, typically made from materials such as carbon fiber, fiberglass, or plastic. The choice of material affects the flexibility and efficiency of the fins.
• Wetsuit: A suit that provides thermal protection and buoyancy control. The thickness of the wetsuit can vary depending on the water temperature.
• Weight Belt: Used to achieve neutral buoyancy at a certain depth. The weight remains constant throughout the dive.
• Mask: A low-volume mask is preferred to reduce the amount of air needed to equalize pressure at depth.
• Nose Clip: Some divers use a nose clip to assist with equalization.

Technique

In Constant Weight Bi-Fins, the diver must rely on efficient finning techniques to maximize propulsion while minimizing energy expenditure. Key aspects of the technique include:

• Streamlining: Maintaining a streamlined body position to reduce drag.
• Kick Cycle: A consistent and powerful kick cycle, often described as a "flutter kick," is essential for efficient movement.
• Equalization: Proper equalization techniques are crucial to prevent barotrauma as the diver descends.

Rules

The rules for Constant Weight Bi-Fins are set by organizations like AIDA and CMAS. Key rules include:

• The diver must use the same weight throughout the dive.
• The use of propulsion aids other than bi-fins is not allowed.
• The diver must return to the surface with the same equipment they started with.
• A dive line is used for safety, but the diver cannot pull on the line for assistance.

Records

As of the latest updates, the world records for Constant Weight Bi-Fins are:

• Men's Record: Held by Alexey Molchanov with a depth of 118 meters.
• Women's Record: Held by Alessia Zecchini with a depth of 95 meters.

Training

Training for Constant Weight Bi-Fins involves a combination of:

• Cardiovascular Fitness: To improve overall endurance and oxygen efficiency.
• Strength Training: Focused on leg and core muscles to enhance finning power.
• Breath-Hold Training: To increase lung capacity and breath-hold duration.
• Technique Drills: To refine finning technique and body position.

Safety

Safety is paramount in freediving. Divers should always:

• Dive with a buddy or safety team.
• Use a dive line for orientation and safety.
• Be aware of their limits and avoid pushing beyond them.

See Also

• Freediving
• AIDA International
• CMAS

References

• AIDA International. "AIDA Freediving Rules and Regulations."
• CMAS. "CMAS Freediving Competition Rules."