What is Critical Swim Speed(CSS) & why we use it

CSS stands for Critical Swim Speed or, alternatively, Threshold Pace.

Critical Swim Speed (CSS) was researched during the early 1990s, providing an understanding of the body's response to various swim intensities and developing a simple measure of aerobic capacity while swimming.

Although CSS was not invented by Swim Smooth, we have combined this concept with a tempo trainer to develop an efficient method for long-distance swim training. This approach targets training to achieve superior pacing skills and ensures that training occurs at the appropriate intensity.

What is a Threshold? It refers to the point at which a swimmer's body begins producing lactic acid faster than it can process it. This transition marks the transition from primarily aerobic to anaerobic energy systems.

Determining Your Critical Swim Speed (CSS) Critical Swim Speed (CSS) refers to the pace a swimmer can maintain over a distance of approximately 1500 meters, akin to the Olympic triathlon distance. Instead of conducting a 1500-meter time trial, CSS can be estimated through a mathematical calculation that involves your maximum effort times for 400 meters and 200 meters. By analyzing the difference between these two times, you can estimate your CSS. You can calculate your CSS on the Swim Smooth Guru page here.

Comparing CSS zones to Blood Lactate & swimming pace

Why train around your threshold pace and induce discomfort?

Training around your threshold pace enhances both aerobic and anaerobic fitness, enabling you to maintain effort for extended durations. As evident from the graph above, we work within a narrow range of seconds, making precise pacing a crucial aspect of developing every fitness aspect. Some ranges are more challenging than others, as we are working on different intensities.

Embrace the challenges posed by pacers to gain insights into your pacing and fitness journey. Look out for our next post on how to use a Finis Tempo Trainer!