The importance of the muscle confusion principle is well known. If you keep working your body the same way for months on end, it will adapt. And finding a suitable lifting routine to replace the one your currently on can be a headache.
Vince Gironda (November 9, 1917 – October 18,1997) was an American professional bodybuilder, author and owner of the celebrity-famous Vince’s Gym. His nickname was the Iron Guru.