Hallmac:The best.....with the current frog, against the current dpv...
I love it! rofl
For work I don't have a say about the current... so I've found that for currents up to about 1 knots a frog kick works best and gives me the best return for investment so to speak (energy vs time vs speed etc.. whatever ) for currents up to 2 knots a flutter kick if I need to swim for extended lengths of time works best for me (till I can catch the boat and hang on) I'll break up the time with dolphin kicks and frog kicks to rest muscles, but it's not fun and often times I have to measure my progress in inches across the sandy bottom... yesterday was one of those days ... my arms are sore today from holding onto the bottom of the boat while resting my legs - lol
fwiw - it took several weeks of snorkeling for my leg muscles to "acclimate" to jets from my old velocity snorkel fins... but it was well worth it
The comments above about frog kicking are very good btw - no need to fight the water. I like to picture my fins like a butter knife slicing through the water on the "load" part of the frog kick. Keep as much of the power stroke within your "slipstream" too - no need to add resistence to your kick (means frog kicks don't have to be really wide to work well)
Aloha, Tim