If you’ve been training back with any consistency for any period of time, there is no doubts you’ve began enjoying some of the effects of training the muscles of the upper back. You look thicker when standing, both clothed and unclothed. You feel stronger in just about any movement you face, including leg exercises such as squats, because your back holds the bar much better. You’re gaining weight, and your traps and shoulders look better too. You’re filling out your frame.