I have been doing chest and tricep together for quiet a long time. Its high time I decided to change my routine.I have two options either i train chest with back or with shoulders. If I train chest and Back, probably its too much to absorb at a same time.As both these muscle groups are big and make you feel fatigue and tired. While shoulder and chest makes me think that, If i train my upper chest then i won't be able to lift much with my shoulders later on . Kindly suggest me the right combination.