When you wear a formal shirt at work you’re entire body is covered and it’s difficult to tell weather you really go to the gym or not ! You might have perfect lean sharp body however you look sick !
It’s frustrating sometimes, that’s why people try to get bigger to look bulky no matter they also put a lot of weight on their belly but it’s not seen on shirts so why care !
Also sleeving up your shirt and keeping few buttons open might make your muscles , nerves and few cuts seen giving people hint that yeah you do go to the gym but you’re a work at you’re not supposed to look that way !
Along with bigger muscles you need to concentrate on your forearms, collar, calves , shoulder sides and abs the most ! There are smaller group of muscles and can be bulked up by using DTP workouts by Kris Gethin. Higher reps and concentration (slow contraction) will give you perfect fit look on shirts. Try it. More information on DTP available on the internet.
If you are fit and awesome inside your appearance at work in formal attire should not bother you much. However, if it does bring you down here are a few tips worth considering. Wear right size. Oversized clothes will make you look weak and skinny. Wear good combination of colours – Dark and Light. Keep a good posture.