Question: What is the best way to frog kick with propeller fins?
Answer: To use the standard frog kick, stretch your legs apart in a sideways manner during a rest stroke (or outward stroke) and then push water with the bottom of the fins while bringing your fins back to center. A sculling version of a frog kick can include orienting the fins approximately parallel or at a slight angle to the bottom on the outward stroke and then orienting the bottom surface of the blades toward each other on the power stroke portion of the frog kick. Speedometers show that propeller fins produce excellent propulsion speeds with these strokes even though there is little or no leg resistance. The stiffer versions will give more of a bite or feel while the more flexible versions will offer increased relaxation.
You can also enjoy a two-stroke frog kick since the twisting blades of propeller fins are designed to provide propulsion on both the power stroke and the return stroke. This can be done during the return stroke by pushing water with the top of the blade in an outward sideways manner while letting your ankles flex and pointing your toes behind you. During this outward stroke motion, the water is funneled backward through the split to propel you. You can also quickly snap the fin when you reverse the stroke direction from the outward stroke to the power stroke and you will rocket ahead. Short rapid back-and-forth strokes will produce high speeds with minimal effort. Try both stiffer and more flexible propeller fins to see which feels best to you.
In addition to using frog kicks to reduce silt-up in cave and wreck environments, you can also use the modified flutter anti-silting kick. Use rapid small kicks from the ankle and lower legs while bending the knees upward to keep the fins away from the bottom. Propeller fins provide efficient propulsion with small range flutter kicks.
In environments prone to silt-up, a skillful toe or ankle flutter kick that use no leg movement at all with propeller fins can allow you to sustain cruising speeds exceeding 1 mph while minimizing turbulence and silt-up. Frog kicks with paddle fins use a lot more energy to sustain the same speeds. While the large leg movements of frog kicks can create turbulence and vortex shedding that can spread out to the bottom, surrounding walls and ceilings of enclosed environments such as caves and wrecks, the minimal movements of an ankle or toe kick with propeller fins can minimize turbulence in the water for maximum reduction in silt-up with significant increases in propulsion efficiency and energy conservation. In addition, the small motions of a reduced flutter kick or toe kick offers improved fine tuned maneuvering through restricted passageways in caves and wrecks while minimizing leg movements, turbulence and silt-up.
From:
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