WHAT IS CRITICAL SWIM SPEED (CSS)?
Critical swim speed is considered to be aerobic threshold swimming. Usually what they can maintain swimming without exhaustion. We would consider this at Evolve Triathlon Coaching to be 1000m.
This is where your lactate production is similar to the bodys ability to get rid of lactate.
CALCULATE YOUR CSS :
HOW TO WORK OUT YOUR CSS TIME?
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Working this out can be done in a 25 meter or a 25 yard pool.
Simply warm up then do a 400 time trial and time yourself. Then have a good break (10 minutes) doing some easy swimming.
Finally do a 200m or yard time trial as hard as you can.
After this, put both your times in the above columns. The calculator will work out your CSS or threshold time for 100 meters or yards.
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Check that you swam the 200m at a faster time per 100m than the 400m. This should always be the case because it’s a shorter distance. This is essential or the calculation will not work!
WHAT ARE THE BENEFITS OF USING THIS?​
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Critical swimming speed helps improve that aerobic capacity. These times should be used to to pace yourself throughout a threshold set, it is a goal time to aim for, making sure that you aren’t going to hard or too easy – Pace Awareness.
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It really is race pace swimming- Maybe not for a short distance like 100m, but this will help improve that race speed for a Half Ironman and Ironman distance.
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EXAMPLE SESSIONS ​
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I would start with 100’s, remember these may feel easy, but by the time you have hit 10 of them, you will feel it! Then move to 200’s, then again to 400’s.
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Below I have what beginners should do, then Intermediates and Advanced in brackets ( ).
Main sets:
8 (10), (12), x 100 @ Threshold pace – Rest 15 seconds
4, (5), (6) x 200 @ Threshold pace – Rest 20 seconds
8, (10), (15) x 200 @ Threshold Pace – Rest 20 seconds
3, (4), (5) x 400 @ Threshold pace – Rest 30 seconds
WHEN TO REPEAT THIS?​
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Repeat this test every 6-8 weeks to see the improvements. Set out your weeks so you have a variety of swims.