Swimming for distance is entirely about EFFICIENCY. Water is 600 x as dense as air. You can run with sloppy ass form and get away with it. Everything you do in the water that wastes energy or creates drag is massively amplified and slows you down. A small mistake repeated over the couple hundred strokes on your swim test can be the difference. You need to focus on how to become efficient with your stroke, breathing recovery, etc.
The guys that really helped me out when I was training had me focus on:
1) being confident and comfortable in the water, so you can
2) RELAX as much as possible and
3) pay attention to what is efficient and what creates drag.
One of the main reasons to swim the combat recovery stroke (AKA "underwater recovery" - the spec ops version of the sidestroke) is that you can do it for a LONG time if you are smooth and aerobic. We had many dives and swims over the 3 and 4 hour mark. You can't swim that long if you're wasting energy or trying to go 100% -- LSD or Long Smooth Distance.
Being efficient means: relaxed breathing, LONG purposeful smooth strokes that let you GLIDE as far as possible till you start to lose momentum, keeping your hands close to your body on the returns, powerful kicks, long reaches, smooth head turns for breaths, leading arm tucked against your head, hand position... Learning the right kick for this stroke is unusual, and requires you to pull your upper knee really high and have a very strong kick to straight legs. This is completely different than the smooth flutter kick you'll learn for this stroke with fins; but focus mainly on the no fins plan for now. You need to figure out how long to glide before you coil for your next stroke. You need to figure out if you're able to swim on both sides (recommended but harder to learn) or if you're so much faster on one side that you'll always swim that side for the test. Eventually you need to learn to swim on both sides comfortably (so you can follow the shoreline and swim with a buddy). I can't stress enough that you need to
think REACH, GLIDE, BREATHE, PREPARE on every stroke. Really pull those legs up far to prepare for your kick. Once you get those basics and you're efficient; then move on to the little stuff like only rolling your head far enough to get mouth out of the water.
What you need to do is get some coaching if possible from somebody who has done it. Start here:
Find a Naval Special Operations Mentor - SEALSWCC.COM | Official Website U.S. Navy SEALs There is some good information on the site, and better yet the community has setup a Mentor program that you may be able to hook up with a former team guy or SWCC fellow that can help you with technique.
If that fails, get someone to video tape and time you for about 200 yds using one technique. Then take a short break. Change one thing (like a different kick, or crossing a few inches your feet at the end of the kick to squeeze out the last of the energy, breathing every other stroke, or turning your hips as soon as the kick finishes to roll for the breath, etc). Compare the video of first time and second time. Compare the times. Which version was faster? Which was more tiring? Did one version make you cramp/chafe/injured?
Couple other tips:
- learn to tread water using the bicycle kick, and no hands. Google it, that is the technique used by water polo players. Once you have the basics, practice with your hands out of the water for a LONG time. Then do it holding one of those frigging water bricks or a 10lb laminated barbell.
- Keep in mind that this minimum fitness test is only a baseline test. It wont even be a regular workout at BUD/s or in the teams, it is more like the starter that you'd do as part of a 2 hour PT session. May have changed now, but back when I was in you took this test again on 1st day and they kicked you out if you didn't pass; then had a much harder test (800M swim, 100 push/sit, 10 pull, 3mi run) at the end of indoc phase 2-4 weeks later.
- Learn to breath with your head out of the water as little as possible. I like breathing every other stroke. Most of the time you'll get a decent breath, but sometimes a wave or a turn in the pool or another swimmer will make it not happen. WAIT till next stroke, don't keep trying to catch the breath on that same stroke or it kills momentum. You can't do that if you're not relaxed.
- Use your push off the wall to explode and glide - get that free ride until momentum starts to fade. This will help your times in a pool and also saves energy.
- Your workouts probably need to focus on: endurance, core strength, and being able to move your body weight around efficiently. You're not going to need max bench press numbers or stage ready biceps; but you need to be able to run an obstacle course efficiently and carry a bunch of crap in a pack; and run stupid distances daily... Plenty of other sources of info.
- Unless you swam breaststroke on a swim team or something, I see zero reason to train with it at this point. Nobody was allowed to use it in training after the initial test. In real world I have only used it when approaching a drowning swimmer, or trying to get out of the water w/ dive gear.
FWIW I was always comfortable in the water as a kid, but never swam a swim meet in my life. Once I started training with team guys that knew what they were doing I became a really good swimmer (at combat sidestroke - I still sucked at freestyle compared to some guys and never did learn a decent breaststroke without fins). Eventually I was crushing the 500 with several minutes to spare. Even then working with a friend, I changed my kick pattern 3 weeks into BUD/s because it was more efficient for me, and ended up with the 2nd best swim times in my BUD/s class. That said, thinking I was a decent swimmer - at one of my units we had this guy who was around 40, a regular smoker with a bit of a beer gut (for a SEAL). When he got in the water, he completely crushed everyone - it was embarrassing how much faster he was than everybody else. Turns out the dude was on one of our olympic swim teams... It is all about efficiency and training...
Good luck