Strides are short, relaxed accelerations, usually 15-25 seconds, finishing close to mile or 5K pace but never all-out. They are one of the simplest ways to keep speed and good mechanics in a mostly easy training week.
Typical dose: 4-8 strides after an easy run, with full walking or jogging recovery
They carry very little fatigue because the efforts are short and relaxed
They help maintain neuromuscular coordination and can make faster sessions feel smoother
Good surfaces are flat grass, a track or a quiet flat road
A good structure: after an easy run, walk for a minute, then 6×20 seconds, building from easy to about 5K pace over the first half and holding it relaxed for the second half. Walk or jog back for 40-60 seconds. Twice a week is plenty for most runners.