What you do between hard intervals depends on the purpose of your workout
This alleviates stress and impact between short, fast reps when you’re building speed and strength. Avoid dropping your hands to your knees, as this could cause lightheadedness.
Newer runners benefit most from walking between repeats of at least 400m – it brings your heart rate down but, crucially, keeps blood flowing to clear waste products.
It keeps your heart rate elevated, extends the distance of your workout and simulates laterace fatigue. It is good recovery for most workouts carried out at less than all-out effort.