Designed Originally for Ultimate Freedom of movement. Loose fit or those that know gains don't have to be mirror every set. The cut and drape accentuate the classic physique dynamic. This is true Bodybuilding.
We see an increasing trend for both Men & Women to oversized retro cut garments. These tend to be the serious gym members focused on their gains and not attention. Wanting freedom of movement and a drape that hints at their development.