Critical Swim Speed (CSS) Calculator
Calculate your Critical Swim Speed from 400m and 200m time trials to determine your aerobic threshold pace for effective training.
Inputs
Results
CSS Pace per 100m
97.5 sec
How to Use This Calculator
- Complete a 400m time trial and a 200m time trial in training.
- Enter your 400m Time and 200m Time in minutes and seconds.
- Review your CSS Pace per 100m — this is your Critical Swim Speed threshold pace.
- Use CSS Pace to set your threshold intervals and aerobic training targets.
- Compare your 400m and 200m average paces to assess pacing consistency.
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