my 2 pennies worth.. have got roped into doing a trialthon with work 1st Octber. it’s an open water swim of 1500 metres.
Like the OP in the pool I can blast out a good breast stroke and can do a mile in about 40 mins.
Front crawl though, despite my best efforts, I could only ever manage 1 or 2 lengths before spluttering.
So tried open water swimming at a local boating lake a few weeks ago. Bit nippy in trunks (everyone was in wetsuits), but cracked on with breaststroke. (just like being on holiday, minus the sun, sand and cheap beer.) safety bloke who was recording the times of entry/ exit from the water said just try 20 mins first, see how the cold water affects you.
Like i said, was cold but after a few mins warmed up and did 4 laps of the 400m cct no probs.
that was start of July, but thanks to workand an algae break out at the pool I had to carry on training at the pool on my alledged front crawl.. where I got up to the lofty distance of 2 lenghts ( 50 meters ) with out gasping for breath.
Got myself a wetsuit form local tri shop ( blue seventy spirt for 115 quid ) got to try it for the first time 2 days ago.
A wetsuit does help with leg buoyancy for the front crawl. the open water place is marked out with 4 buoys in diamond pattern , each a 100 meters apart. I find that in the open water, I could swim slower , and get to do a 100m leg, tread water get breathe back, then crack on again. However after 2 laps was blowing out my hoop so swam to the side to get out. Had a chat with the safety bloke, saying I just couldn’t sort out my breathing, as was trying to do 3 strokes, breathe, 3 strokes breathe, 2 stroke breath and spot. ( spot= looks where the **** Im going). he said when he’s fresh in the water he does 3 strokes to every breath, but when tried, drops down to 2, and spots just before the lead hand goes into the water..
So back out, tried the 2 strokes, breathe and spot..**** me backwards.. could do the 100m between the buoys without looking like a floundering asthmatic pit pony!! tried this for one lap to find which side I perferred breathing on, then last last , did the 400 meters non stop. Came out the water beaming!! Now I can do the breathing I can work on my stroke technique, so well happy..
Just give it a go.. but short durations to begin with, walk in slowly to the water to give the body time to acclimatise. A wetsuit will help no end.. wiggle do their OCRA TRN one for 100 quid and gets a good write up, my blue70 sprint is on sale for about 80 quid from cyclesurgery.