Probably the hardest sport to analyze the physiological improvements of training is swimming. Submersion in water makes V02 max testing very difficult, almost impossible. I’ve tried lactate analysis and had mixed results. Generally I find lactate levels are always high and deciphering zones can be tricky.
I’m not a big fan of using time trials to assess fitness because it requires the testee to be consistent (and highly motivated!). I’d rather use physiological markers mentioned above. However one test which I do like for swimming is the 400 m time trial. Do a quick search through scientific journal articles and you’ll find the 400 m time trial is one of the best tests to assess swim fitness because it correlates highly with V02 max. The 400 m TT is also popular with coaches because of its relatively short length (<6 minutes for an average swimmer).
Because the test is relatively short, you can swim for a longer period of time prior to the test. I like to use 50 m efforts prior to the test of varying intensity to get the heart rate up. Remember, the 400 m TT is short and you need to almost reach maximum effort for the duration of the swim.
Example set: 12 x 50 m 3 on 60s @ 85% effort, 3 on 50s @ 90% effort, 3 on 60s @ 95% effort, 3 on 1:10 @ 100% effort
You’ll need to swim in a 25 or 50 meter pool. Have a clock nearby so you can time your effort. Ideally you’d have someone count your individual lap times and strokes (this is very useful and will be explained later) or better yet, video the entire session.
Here is an example of test data recorded from a recent triathlete who did the 400 m TT in a 25 m pool.
Total time for the 400 m was 6 minutes and 8 seconds (6:08). Below are the splits for each 100.
1st 100: 1:28
2nd 100: 1:32
3rd 100: 1:34
4th 100: 1:34
So using this data, zones (or efforts) can be assigned for the athlete to help them progress in the pool. I’m going to use 100 m intervals to describe each zone.
There are 5 zones that I use for swimming: Sprinting (<105% of V02 pace), V02 (100-105% of V02 pace), Intervals (95-100% of V02 pace), Threshold (90-95% of V02 pace), and lastly Sub Threshold (<90% of V02 pace).
The V02 max pace as mentioned above is the average 100 m time from the 400 m effort. From the data the average 100 m effort was 1:32. So the zones for this athlete would be:
I’ll continue shortly on how to design swim sets based on these numbers.