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Load management

Acute:chronic workload ratio calculator

Enter your training load for each of the last four weeks. The calculator compares your most recent week against your four-week average — the ratio that the load-and-injury literature is built on.

How to use it

Use whatever load unit you already have, as long as it is the same one every week. The most practical for amateur sport is session RPE: rate each session out of 10 for difficulty, multiply by its duration in minutes, and add up the week. A 60-minute session you rated 7 is a load of 420.

Count your games. They are usually the single biggest load of the week and the one people forget, which is exactly how a congested fixture block sneaks up on you.

The detail

What the number means

What the number means

An ACWR near 1.0 means this week looks like a typical recent week. Ratios above roughly 1.5 are the pattern associated in the literature with raised injury risk — not because a number caused anything, but because it describes doing much more than you are conditioned for.

Sustained ratios well below 1.0 mean the opposite problem: your chronic load is falling, and a return to normal training will itself register as a spike.

What it is not

It is not a diagnosis, and the statistical methods behind some of the early ACWR research have been genuinely and reasonably criticised. Treat it as one signal alongside how you feel, how you are sleeping, and whether your resting heart rate and HRV are behaving.

The underlying finding survives all of that criticism and is much simpler than the formula: big jumps in training load are risky, and the week after a break is the most dangerous week of the year.

Read next

The full guide to training load covers how to measure load without a GPS unit, the three situations that catch people out, and what to do about each.

FAQ

Common questions

What is a good ACWR?
Roughly 0.8 to 1.3 is the range most practitioners aim to stay within — training is progressing but not spiking. Above about 1.5 is the pattern associated with raised injury risk in the load literature.
How do I measure training load without GPS?
Session RPE: rate each session out of 10 for difficulty and multiply by the duration in minutes, then sum the week. It is crude but it correlates well with more expensive methods and it is what most amateur sport uses.
Should I include games in my load?
Yes, and they are usually the largest single load in the week. Leaving them out is the most common reason an ACWR calculation understates a congested fixture block.
Keep reading

Related

Training load explained

What ACWR can and cannot tell you, and the three situations that actually catch athletes out.

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Deload weeks

The planned lighter week that stops the forced one.

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Recovery & readiness

How Train Smart tracks load and readiness automatically from your sessions and Apple Health.

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Or let the app do it every week

Train Smart runs this calculation continuously — recalculating your working weights, your conditioning paces and your load every session, without you opening a calculator.

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