Figure 5
From: The effect of standing and sitting postures on breathing in brass players
A comparison of the level of abdominal muscle activity and movement of the chest and abdominal wall during performance of a trumpet study in different postures by a student player. The electromyographic signals from both the external oblique and rectus abdominis are markedly lower when sitting on a flat seat or downward sloping seat than when standing. A.U. arbitrary units.