Kinhin's function is easiest to see inside a sesshin, the intensive multi-day meditation retreat that structures Zen monastic and lay practice around long, repeated blocks of seated zazen, since the walking periods are built into that schedule deliberately rather than offered as an optional break from it. A typical sesshin day alternates zazen periods of twenty-five to forty minutes with short kinhin intervals of five to ten minutes threaded between them, repeated across many hours and, in longer retreats, across several consecutive days, a rhythm the schedule is designed around rather than merely tolerates, since practitioners sitting motionless for that many consecutive hours would otherwise face serious physical strain that kinhin's brief walking interval is specifically positioned to relieve.
The practice traces to Chan Buddhist monasteries in medieval China, where sustained group meditation across long training periods already required some accommodation for the body, and the Japanese Zen schools that inherited Chan practice preserved and formalised the alternation as Soto and Rinzai developed their own distinct paces, the deliberate half-step-per-breath of Soto kinhin and the markedly brisker walk of Rinzai reflecting each school's wider difference in temperament, Soto's emphasis on quiet, gradual cultivation against Rinzai's more vigorous engagement with koan practice.
Retreat centres outside Japan that have adopted sesshin format for Western students have generally preserved kinhin as a structural fixture of the schedule rather than treating it as optional, since without it the physical demands of a multi-day sitting retreat would be considerably harder for most participants to sustain.