Just as an athlete finds it necessary to limber up ahead of a training session, regular warm-ups should form an important part of every brass players practice session,.  Warm-ups are essentially embouchure training and muscle building exercises designed to allow the muscles and tissues involved to become supple. They also promote good tone, breath support, flexibility and range.  They typically include long tone studies in the middle and low registers, scales and lip slurs. Some teachers also recommend that players “warm-down”, especially after a demanding practice session.  A warm-down usually consists of a few soft notes in the low register designed to relax the lips and prevent stiffness.