This week
Last 4 weeks
Assessment
| Assessment | ACWR |
|---|---|
| Undertraining | 0.0 – 0.8 |
| Safe zone | 0.8 – 1.3 |
| Caution | 1.3 – 1.5 |
| Elevated risk | > 1.5 |
How does the acute:chronic ratio work?
The ACWR divides this week's load (acute) by your average weekly load over the last four weeks (chronic). A ratio of 1.0 means this week matches your habit. If the ratio jumps well above that, you are stacking load faster than your body can absorb.
The zones explained
Below 0.8 you are tapering or training lightly. Between 0.8 and 1.3 is the 'sweet spot' with the lowest injury risk. Between 1.3 and 1.5 calls for caution. Above 1.5 the risk of overload rises sharply — a large, sudden spike is more dangerous than a high absolute volume.
Building up sensibly
Increase your weekly volume gradually (the well-known 10% rule is a rough guide). Schedule recovery weeks and take extra care after illness or injury, when your chronic base has dropped and a normal week suddenly produces a high ratio.
Frequently asked questions
Other tools
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