DIR fin technique questions

[Lenaxia]

Congratulations on starting really the only thread I can think of on DIR outside the DIR forum that produced more or less appropriate, rational discussion

I never expected this to be such a hot topic! I'm glad it hasn't devolved into bickering yet though. I think it would be interesting if we could create a standard for experimentation that people could perform and post their results. Perhaps to evaluate the efficiency of certain kicks at slow and fast speeds.

 

[Dyno Bill]

There is a time and place for most things. This thread actually just hits the nail on the head. Different types of diving require different tecniques just by virtue of what they are.I used to live on the beach next to a 20 mile long bike path, I loved rollerblades as they were incredible exercise that was also fun. I used 5 wheel speed skates and also had some 4 wheel rockered hockey skates. Both pairs worked really well for what they were intended for but you couldn't play hockey on speed skates. Using that format the different scuba styles are similar because they are in water, but thats it. You wouldn't be advised to enter an overhead environment with silt swimming like a U Boat. You wouldn't hunt the kelp forest doing a frog kick, a seal lion might want to mount you or something equally embarrassing. I feel understanding the variations required for the different styles of diving is a good thing and respecting the rights of everyone to do his or her thing as they feel fit for themselves is also a good thing. That being said I will refrain from any further wise type statements..... at least for now

 

[axyto]

frog kicking is mainly for efficiency in energy consumption under water, why would you do a tiring flutter when you can kick and glide with frog kicks, i am also a competitive swimmer and sure is breast stroke kick and frog is slightly different but and dont find any problems with frog kicks under water even on long distance.. practice and more practice will give you a hold of it..

 

[Lobzilla]

I thought I was doing a frog kick and liked it until Trace Malinowski showed me what a frog kick really is. Now I LOVE it. This technique can range from a relaxing 'kick and glide' mode to an explosive forward jolt if you need to reach your buddy in a hurry.

Think about force vectors. On a flutter, your fins are going up and down. But that is not where we want to move. So we use flimsy fins and split fins that bend to generate some forward force by deflecting the water backwards. However, our entire legs are going up and down and create friction that is not doing us any good. This up and down just wastes energy.

During a frog kick with the correct fins we are taking the equivalent of two pieces of plywood and shove them backwards against the water. First they go back flat and then we squeeze the water out between them. Meanwhile our legs move very little and little friction is produced there.

If you want the swimming analogy, the frog, if done correctly, is like pushing yourself off the wall at the end of the lane. It does not get any more efficient than that.

The only disadvantage is that the efficient push and shove of the frog is discontinuos. If we want or need continuous propulsion, we have to resort to the inherently less efficient flutter (or buy a scooter).