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How to Calculate the 505 Change of Direction Deficit
The 505 change of direction deficit is a way to separate some of the straight-line sprint time from a 505 test result. The calculation is short; getting comparable inputs takes more care. Here is the formula, a worked example and the limits to keep in view when comparing athletes.
The formula and the two times it needs
The 2016 study by Nimphius and colleagues calculated change-of-direction deficit by subtracting a 10m linear sprint time from the 505 time:
505 change of direction deficit = 505 time − matched 10m sprint time
Both inputs are times in seconds. The result is also expressed in seconds. The 505 time includes acceleration, approach running, braking, the 180-degree turn and the run back through the timing line. The linear sprint split estimates the time needed to cover the corresponding straight distance without the turn.
This difference is not a direct measure of every quality involved in changing direction. It is a simple subtraction intended to make the turn-related portion easier to inspect alongside sprint speed.
Work through one example
Suppose an athlete records a 2.48-second 505 trial and a 1.82-second 10m linear sprint split collected with a matched start and timing method.
2.48 s − 1.82 s = 0.66 s
The calculated deficit is 0.66 seconds. Report the source times as well as the difference; a deficit alone hides the performance that produced it. These numbers are an example, not a target or a published norm.
| Measure | Example | What it represents |
|---|---|---|
| 505 time | 2.48 s | Timed 505 trial under the stated protocol |
| 10m sprint split | 1.82 s | Matched straight-line split |
| 505 deficit | 0.66 s | 505 time minus the 10m sprint time |
Match the split before comparing results
The subtraction only helps when the inputs belong together. Use a sprint split from the same athlete, session and start convention. A flying 10m split should not be mixed with a 505 that starts from a stationary position and includes the approach. That changes the question the number answers.
Write down the start position, timing-line placement, approach distance, turning direction and the split used. If the test includes both left- and right-turn trials, calculate each side separately. Averaging sides can hide a meaningful difference, while choosing only the best trial can conceal inconsistent execution.
For repeat sessions, keep the surface, footwear, warm-up, instructions and gate layout as consistent as practical. Use a familiarization trial before recording results. The 505 familiarization guide and S-007 split reporting guide cover related setup decisions.
What the research does and does not support
In the cited study, 17 cricketers completed 505 testing to both sides and 30m sprints with a 10m split. The 505 time was associated with sprint performance in that sample, while the calculated deficit was not. That result supports looking at the two measures separately; it does not establish universal cutoffs or prove that one test predicts match performance for every sport.
The researchers also describe the 505 deficit as a more isolated measure than raw 505 time, not a complete account of agility. Agility includes reacting to an opponent or cue, while a preplanned 505 turn does not. Treat the score as one test result in a broader assessment, not a diagnosis or selection rule.
Read the journal article record alongside the DOI record for the study's full method and limitations. The sample is small and sport-specific. Do not turn its findings into population norms.
Set up timing so the subtraction is useful
For the 505, the athlete accelerates toward a line, places a foot on or beyond it according to the selected protocol, turns and sprints back through the timing gate. Mark the approach and turn line precisely. Decide in advance whether the timing line is the start/finish or whether the athlete runs through separate gates; changing the layout changes the recorded time.
A multi-point system can record more than one split, but additional gates do not fix an inconsistent protocol. The S-007 layout guide explains split placement, while the gate alignment guide covers beam checks. For broader planning, see the athlete testing data workflow and timing data export guide.
Before the session, test the start and finish triggers with a walk-through, then run a familiarization repetition. Keep the athlete's raw 505 and sprint times in the record. If a split is missing or a turn is invalid, mark the trial as incomplete instead of filling the gap with a time from another protocol.
Questions about the 505 deficit
What is the 505 change of direction deficit formula?
Subtract the matched 10m linear sprint time from the 505 time: 505 change of direction deficit = 505 time minus 10m sprint time. Keep the start, distance and timing method consistent.
Does a higher 505 deficit always mean worse agility?
No single number is a universal agility grade. Compare athletes only when the protocol is matched, and interpret the result with sport demands, turning side and measurement reliability.
Can I subtract a 30m sprint time from a 505 time?
Not as the standard calculation described in the cited study. It subtracts a matched 10m linear sprint split. Use a different distance only if a validated protocol defines it and label the result accordingly.
Report the inputs, not only the score
For example, a useful report shows the 505 trial, the matched 10m split, the calculated difference and the turning side. Add the protocol and timing setup so a coach can reproduce the comparison. When the inputs do not match, keep the raw results and do not present the subtraction as a standard deficit.
The calculation is a lens, not a verdict. Use it to ask a better follow-up question about sprint speed, braking or turning mechanics, then choose a test that directly measures the quality you want to assess.