Watch metric
Ground Contact Time (GCT)
Ground Contact Time (GCT) Definition
How long each foot stays on the ground with each step, measured in milliseconds. Usually needs a compatible strap or pod.
For more experienced runners, this can indicate, along with cadence, things about your form. Generally a longer Ground Contact Time means each foot spends more time on the ground.
This will change depending on how fast you're running.
Is there an ideal ground contact time when running?
No, there is not one ideal ground contact time. Ground contact time varies between runners and changes massively depending on how fast you're running.
Should you try to change your ground contact time?
For almost all runners, working directly on trying to decrease ground contact time isn't something you should put lots of thought into. 99% of runners would improve much more by simply running more and focussing on recovery.
When it helps
Almost never for a beginner. It can be an interesting thing to look at.
When it doesn't
For a beginner, always. It changes with speed and is not a dial you can turn.