Understanding load & ACWR
How VolleyFit turns your effort after every session into a load value and the ACWR – and what the zones mean.
The ACWR (acute:chronic workload ratio) shows how the load of the last 7 days compares with what a player is used to. A sudden jump upwards is considered a warning sign for overload – but the value is not an injury prediction.
How load is calculated
After every practice or game the app asks: How tough was your training? (or your game?). The player chooses a value from 1 (very easy) to 10 (maximum) – the RPE (rate of perceived exertion). The details are in Logging your effort (RPE).
VolleyFit calculates the session load from it: RPE × duration in minutes, given in AU (arbitrary units).
| Session | Calculation | Load |
|---|---|---|
| Practice, 90 minutes, RPE 7 | 90 × 7 | 630 AU |
| Volleyball game, 3 sets played, RPE 8 | 3 × 30 min × 8 | 720 AU |
- Practice: the duration is the time from the event’s start to its end.
- Volleyball game: every set the player actually played counts as 30 minutes. Each player enters their own sets (0–5) in the RPE prompt.
- Games in other sports: the player enters their minutes on court or pitch.
- Workouts count with their intensity and duration, training diary entries with the duration and RPE entered.
Only events where the player is marked Confirmed count. Guests, declines and unexcused absences add no load.
How the ACWR is calculated
- Acute load: total load of the last 7 days (including today).
- Chronic load: average weekly load over the last 28 days. If there’s less than 4 weeks of data, it’s divided by the weeks actually available.
- ACWR = acute load ÷ chronic load, rounded to two decimal places.
A value of 1.0 means: this week was exactly as demanding as an average week. The app also shows the deviation, e.g. “ACWR 1.35 · +35 %”.
The zones
| ACWR | Zone | Meaning |
|---|---|---|
| below 0.8 | Underloaded | More than 20 % below your 4-week average. After a break, build up gradually. |
| 0.8 to 1.3 | Normal | Within the usual range (−20 % to +30 %). |
| above 1.3 up to 1.5 | Elevated | +30 % to +50 % above usual. Keep an eye on recovery. |
| above 1.5 | Overloaded | More than 50 % above your 4-week average. Jumps like this are a warning sign – adjust load. |
If there’s no value yet, you’ll see No data.
Only after 21 days
For a meaningful value VolleyFit needs a 21-day baseline. Until then the app shows a badge “ACWR … %” with the progress, and the info sheet says Building your ACWR with “Day … of 21”. Before that, values would be too noisy and could wrongly flag you as overloaded.
When the value is updated
The ACWR is calculated on the server, not on your phone:
- Every night at 3 am (German time) for the previous day.
- Straight away when you enter or change an RPE, sets played or minutes on an event, and when you create, edit or delete a diary entry.
Where you see the ACWR
As a player: next to the greeting on the dashboard, and in the training diary above the weekly plan. Tapping the badge in the diary opens Load ratio (ACWR) with acute and chronic load, Ratio, Deviation and the explanations How it's calculated and What do the zones mean?.
As a coach in the app: on the team page, the Load card shows how many players are above or below the normal range. Tapping it opens Team load – notable players first, with a 14-day history. On a player’s profile, the Training tab lists their sessions and the Health tab shows the trend.
In the web dashboard
- Statistics shows the Team ACWR (28 days) with the target zone 0.8–1.3, how many players are in the target zone, and a list of all players with filters such as Danger, Warning and Too low.
- In the member view, the Load tab shows the current ACWR, daily load, ACWR trend and individual sessions (4 weeks or 3 months).
- In the roster and member view the dashboard uses just three levels: too low (below 0.8), optimal (up to 1.3) and too high (above 1.3).
The dashboard also requires Premium, and values only appear for players with valid consent. It shows the values the server calculated overnight or after each change.