at home late work out
work on ur lats and ur obliques. ur obliqe muscles cover a part of ur ribs. also, there is a muscle in ur arm pit u can work.
to workthis muscle get into a push up position. keep ur arms locked and lower urself. this will mean ur body will drop but ur arms stay the same. now raise ur body. do u get what i mean? its hard to explain.
to work ur lats lay down underneight a table. be sure u can fully extend ur arms. u should be laying on ur back facing the table. now grab the edge of the tabe and pull ur chest towards it. get ur lower chest to touch the table. this will work ur lats.