Critical Swim Speed Calculator

Critical swim speed (CSS) is a measure of your threshold speed. It is useful for setting training intensities that will help you develop sustained speed over increasingly longer durations.

To test your CSS

1. Warm up (600-1000m, including drills and some short, fast efforts)

2. Perform a 400m time trial (as fast as you can at a sustained pace)

3. Recover for at least 10 mins

4. Perform a 200m time trial

5. Use my calculator to find CSS

Structured swim training

Structured training is one of the most effective way to improve your speed and endurance.

To add structure into your training join my Membership for female triathletes and runners, or contact me about a personalised training plan.