It is particularly important that riders do not squeeze their heels or lower legs into the horse's sides when slowing or stopping, or use the reins as a brace at any time, as these errors send the horse contradictory signals. If riders lose their balance, it is common to grab the mane to prevent jerking the horse in the mouth with the reins of the bridle, though ideally a rider can maintain proper balance by correct placement and use of their thigh and upper calf muscles.