The serratus anterior is a muscle that originates on the surface of the 1st to 8th ribs at the side of the chest and inserts along the entire anterior length of the medial border of the scapula. The serratus anterior acts to pull the scapula forward around the thorax. The muscle is named from Latin: serrare = to saw, referring to the shape, anterior = on the front side of the body
Each stretch in this video should be held for 30-60 seconds and repeated 5-10 reps on each movement.
It can manifest in chest pain even down to the arms. common in people that swim or do tennis.