This research study investigated the timing, intensity, and symmetry of muscle responses during unilateral arm raising. The authors designed the study to validate previous research that proposed that the Transversus Abdominus muscle (TrA) served a stabilizing function based on symmetrical activation during arm raining. The previous research papers were the genesis of isolation TrA training protocols that has been adopted all over the world. These protocols involve a conscious activation of the TrA while attempting to keep other muscles from contracting.