this means swimming with a little nasty band around the ankles and no pull buoy :-)
it can simply be made out of an old bike tube tied in a knot and placed around your ankle so that it prevents you from kicking!
this swimming drills are very effective because we have to exhibit proper body position, higher stroke rate and effective propulsion!
you will quickly learn if one of those aspects is lacking...
-over glide and you will sink
-low stroke rate and you will sink
-poor body position and you will sink
-not a good hold on water with the forearm and you know what? you will sink :-)
the good thing is that if you are able to make it across the pool, you are doing right! simple!
just start with 25m repetitions and build up slowly to 50m, it will make you a more powerful swimmer
actually I'm doing a lot of band only swimming here at palyitas ;-)