Critical Swim Speed: Explained

(page in development, 11/8/14)

The concept of Critical Swim Speed (CSS) was introduced to us from Guy Crawford, a coach and regular at the famous Swim Smooth Program out of Perth, Australia. Conducting regular CSS tests is a great way to determine if an athlete is improving their threshold swim speed, as well as a great way for us to break swimmers down into specific swim lanes based on ability. Finally, a CSS test allows us to calculate unique 'swimming zones' for an athlete, thus providing a means to adjust intensity and determine if an athlete is truly swimming 'easy' 'moderate' or 'hard' for a given segment of a workout. 

Conducting the CSS workout is straight forward. You'll need a 25yard (or meter) pool. After a good warmup conduct the following set:

400 yard Time Trial (best pace possible)

200-400 yard recovery, based on ability. Swim as slow and as easy as needed.

200 yard Time Trial (best pace possible)

From here, we calculate our CSS pace by using the following formula: