What work is appropriate for yearlings and how do you develop a yearling without overloading its developing body?

The yearling year is one of the most misunderstood stages of young horse development because it falls in the gap between the early imprinting work of the foal period and the more structured colt starting of the two or three-year-old — and many horse owners either do nothing with yearlings or overload them with work their developing bodies cannot yet handle. The appropriate work for yearlings is exclusively groundwork — no riding, no significant weight-bearing work, no demanding physical exercise that stresses developing joints and growth plates. The yearling's skeletal system is actively growing and the growth plates in the legs are not closed, meaning any repetitive concussive work on hard surfaces creates risk of permanent damage to joints and bones that will affect the horse's soundness for its entire career. What is appropriate and valuable for yearlings is handling that continues the desensitization and yielding work begun in the foal period: leading correctly, standing tied, picking up all four feet willingly, accepting being touched all over the body including the mouth and ears, loading in a trailer, and basic yielding to pressure from the halter and lead. These lessons require no concussive exercise and develop the responsiveness, trust, and ground manners that make the eventual colt starting safe and efficient. Clinton Anderson specifically addresses yearlings in his foundation training program, noting that yearlings that have been handled consistently through their first year — that lead well, stand for the farrier, load without drama, and yield softly to pressure — start under saddle more easily, progress faster, and have fewer behavioral problems than yearlings that were pasture-raised with minimal human interaction. The investment in yearling handling pays significant dividends when starting time arrives.