uses of canter and gallop

Question
hello sir. trotting a horse would up its muscles. then, what are the uses of cantering and galloping a horse?

Answer
Yes, trotting a horse does build muscle definition..but it also does much more than that. It also teaches a horse to rely on the riders cues, teaches it to stay in the correct gait and at the correct speed dictated. Cantering does the same thing. Your horse should be able to walk, trot, canter and back "on cue" and stay at that speed and gait until otherwise cued not to. So, it is much more than just "up its muscles". "Galloping" is nothing more than a faster canter.