What is CTL in training analysis?

Chronic Training Load (CTL) is a 42-day exponential moving average of daily TSS. It represents your current aerobic fitness level. Most recreational athletes have CTL of 30–60; elite endurance athletes may exceed CTL 120.

How quickly does CTL change?

CTL changes slowly due to the 42-day time constant. To raise CTL by 10 points, you need to sustain higher training loads for 3–4 weeks. Conversely, two weeks of rest causes CTL to drop by roughly 20–25%.

Chronic Training Load (CTL) Calculator

Calculate your Chronic Training Load (fitness) using an exponential weighted average of daily TSS over 42 days. Track long-term training adaptation.

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Chronic Training Load (CTL) Calculator

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Frequently Asked Questions

What is CTL in training analysis?

How quickly does CTL change?