Choosing Bifin Blade Stiffness and Size

Choosing Bifin Stiffness

Soft: Suitable for all women, for athletes with excellent straight-leg bifin technique, and for men who want to use these fins for training and performance. Softer blades are more economic in terms of energy consumption, although it mostly remains a preference among freedivers with more strength whether to choose a soft or medium stiffness.

Medium: Can be suitable for those who rely more on the knee-kicking technique (stronger front kick due to more bent knees) and also for stronger males who use the straight-leg bifin technique. Can also be suitable for strong males who make multiple shallow dives (e.g. fun diving, spearfishing, underwater photography, and safety freediving).

Hard: Can be suitable for very strong and heavy men who dive to mid-range depths who need to overcome resistance (e.g. spearfishers diving in currents). More suitable for the knee-kicking technique.

Choosing Bifin Blade Size

We also offer the choice of a ‘Small’ bifin blade for freedivers who are under 65kg (143lb), shorter than 170cm (5 feet 11 inches), or with shorter leg proportions. Small blades feature 10% less surface area and an adjusted ‘bottleneck’ shape. They are particularly ideal for shorter freedivers because of their ease of maneuverability, while additionally requiring less power and energy spent on kicks. The blade layering structure of Small blades results in a slightly reduced stiffness compared to regular blades of the same stiffness.

Our philosophy is that smaller amplitude, low-effort kicking results in more oxygen conservation and less lactic acid build-up. Paired with an efficient technique, this finning style is favored by many of the top freedivers of today, including Alexey himself.