Yo-Yo Intermittent Recovery Test
Calculate YYIR1 or YYIR2 performance, run a browser-based audio pacer, and follow the evidence-based protocol from one professional resource.
How to perform the Yo-Yo Intermittent Recovery Test
The participant performs repeated 2 × 20 m shuttle runs at progressively increasing speeds. After every completed 40 m running bout, there is a 10-second active recovery covering 2 × 5 m.
An acoustic signal controls the start, 20 m turn and finish. The participant should reach the line at the signal rather than sprinting ahead and waiting.
Course layout
Each bout: 20 m out → 20 m back → 10 s active recovery (2 × 5 m).
Which Yo-Yo test should you use?
| Feature | YYIR1 | YYIR2 |
|---|---|---|
| Starting speed | 10.0 km/h | 13.0 km/h |
| Course | Repeated 2 × 20 m runs | Repeated 2 × 20 m runs |
| Recovery | 10 s active recovery, 2 × 5 m | 10 s active recovery, 2 × 5 m |
| Primary emphasis | Intermittent endurance / ability to recover and repeat intense exercise | Repeated intense exercise with greater anaerobic contribution |
| Typical use | Most widely used version across intermittent-sport populations | Highly trained populations where a more demanding starting intensity is appropriate |
| Primary result | Total metres completed | Total metres completed |
Do not compare an IR1 distance directly with an IR2 distance as though they were the same test.
How Yo-Yo Test scoring works
The clearest primary outcome is total distance successfully completed. Every full out-and-back running bout adds 40 m.
The result can also be recorded as the speed level and bout, for example YYIR1 17.4. For reports and longitudinal tracking, storing both the level/bout and the total distance is useful.
What about “good” and “excellent” scores?
There is no defensible single universal classification table. Published results vary substantially according to the exact Yo-Yo version, sport, competitive level, sex and population.
For professional interpretation, use a reference population that actually matches the athlete or group being assessed.
View full YYIR1 scoring table
| Level | Bout | Speed | Distance | Approx. elapsed |
|---|
View full YYIR2 scoring table
| Level | Bout | Speed | Distance | Approx. elapsed |
|---|
What does the Yo-Yo Intermittent Recovery Test measure?
The YYIR test was developed to assess the ability to repeatedly perform intense exercise and recover rapidly between efforts. This is why it is widely used in intermittent sports rather than as a simple continuous running test.
Repeated intense running
The participant repeatedly accelerates, runs, turns and recovers while the required speed increases.
Recovery capacity
The 10-second active recovery is a defining part of the test and distinguishes YYIR from a continuous multistage shuttle run.
Intermittent-sport fitness
Original validation work linked YYIR performance with high-intensity running during football match play.
Yo-Yo Test vs Beep Test
| Yo-Yo Intermittent Recovery | 20 m Beep Test / MSFT | |
|---|---|---|
| Format | Repeated 2 × 20 m bouts | Continuous 20 m shuttles |
| Recovery | 10 s active recovery after every 40 m | No recovery between shuttles |
| Primary emphasis | Repeated high-intensity exercise and recovery | Progressive continuous shuttle-running endurance |
| Result | Distance + level/bout | Level/shuttle + distance |
| Best fit | Intermittent team-sport demands | General field-based aerobic endurance testing |
What equipment do you need?
Measured 20 m course
Use a tape measure rather than pacing the distance. Course error changes the running demand and compromises repeat testing.
Cones / markers
Clearly mark the start/finish line, the 20 m turn line and the 5 m active-recovery area.
Audible pacing
Use a speaker loud enough for the full testing area. Always test the sound and browser/device behaviour before the assessment starts.
Common testing errors
Protocol errors
- Using the wrong test version or pacing track.
- Setting the running distance incorrectly.
- Omitting or shortening the 10-second recovery.
- Allowing turns short of the marked line.
- Allowing athletes to run well ahead of the signal and wait.
Scoring errors
- Counting an incomplete final 40 m bout.
- Comparing IR1 and IR2 as if they were interchangeable.
- Using generic norms that do not match the population.
- Reporting predicted VO₂max as directly measured.
- Changing protocol or course setup between repeat tests.
Use the free tool now. Save and track results with Cartwright Assess later.
Cartwright Assess is being developed to combine participant records, multiple physical assessments, longitudinal tracking and professional reporting in one platform.
Yo-Yo Intermittent Recovery Test FAQs
What is the Yo-Yo Intermittent Recovery Test?
The Yo-Yo Intermittent Recovery Test is a progressive shuttle-running test designed to assess the ability to repeatedly perform high-intensity exercise with short recovery periods. Participants complete repeated 2 × 20 m runs, followed by 10 seconds of active recovery, while the required running speed progressively increases.
What is the difference between Yo-Yo IR1 and IR2?
Both tests use the same 20 m out-and-back format with 10 seconds of active recovery, but IR2 begins at a higher speed and places a greater demand on high-intensity and anaerobic exercise capacity. IR1 is more commonly used across a broad range of team-sport athletes, while IR2 is generally more demanding and better suited to highly trained populations.
How is the Yo-Yo Test scored?
The primary score is the total distance successfully completed in metres. Each completed running bout covers 40 m. Level and bout can also be recorded, but total distance is the clearest outcome for reporting and comparison.
How far is one Yo-Yo shuttle?
One completed Yo-Yo Intermittent Recovery running bout covers 40 m: 20 m out and 20 m back. This is followed by a 10-second active recovery involving 2 × 5 m of movement in the recovery area.
Is the Yo-Yo Test the same as the Beep Test?
No. The traditional 20 m Beep Test is continuous, whereas the Yo-Yo Intermittent Recovery Test includes a 10-second active recovery period after every 40 m running bout. The tests therefore assess overlapping but different aspects of fitness.
Can the Yo-Yo Test estimate VO₂max?
Published equations can be used to estimate VO₂max from Yo-Yo Test performance, but these values should not be treated as equivalent to directly measured laboratory VO₂max. For professional reporting, any prediction should be clearly labelled as an estimate and the equation used should be identified.
What equipment do you need for the Yo-Yo Test?
You need an accurately measured 20 m running area, cones or markers for the start and turn lines, a marked 5 m active-recovery area, and a reliable audio pacer that follows the correct IR1 or IR2 timing schedule. A tape measure and suitable speaker are recommended for professional testing.
When should the Yo-Yo Test stop?
Standard published methodology ends the test when the participant twice fails to reach the required line in time with the audio signal, or when they stop because of exhaustion. The last fully completed 40 m bout should be recorded.
Can I run the Yo-Yo Test without a CD?
Yes. The test does not require a physical CD as long as the pacing audio accurately follows the correct Yo-Yo IR1 or IR2 timing protocol. This page provides a browser-based pacer using newly generated timing tones rather than reproducing the old commercial CD recording.
Is there an online Yo-Yo Test audio pacer?
Yes. The Cartwright Yo-Yo Test tool on this page includes a browser-based audio pacer for IR1 and IR2. It displays the current level, bout, running speed, distance and recovery period while generating the required pacing signals.
Evidence base for this tool
The calculator and pacer are based on the published YYIR protocol: repeated 2 × 20 m runs at progressively increasing speed, separated by 10-second periods of active recovery (2 × 5 m). The systematic review describes the initial IR1 and IR2 stages and the subsequent 0.5 km/h increase after blocks of eight bouts.
- Krustrup P, Mohr M, Amstrup T, et al. The Yo-Yo intermittent recovery test: physiological response, reliability, and validity. Medicine & Science in Sports & Exercise. 2003;35(4):697–705. PubMed.
- Krustrup P, Mohr M, Nybo L, et al. The Yo-Yo IR2 test: physiological response, reliability, and application to elite soccer. Medicine & Science in Sports & Exercise. 2006;38(9):1666–1673. PubMed.
- Bangsbo J, Iaia FM, Krustrup P. The Yo-Yo intermittent recovery test: a useful tool for evaluation of physical performance in intermittent sports. Sports Medicine. 2008;38(1):37–51. PubMed.
- Schmitz B, Pfeifer C, Kreitz K, Borowski M, Faldum A, Brand S-M. The Yo-Yo Intermittent Tests: a systematic review and structured compendium of test results. Frontiers in Physiology. 2018;9:870. Open-access review.
For professional use, standardise course measurement, test version, pacing method, supervision and termination criteria. This resource is for professional education and field-testing support, not diagnosis or medical advice.