I have a smal workout facility at my work, with life fitness machines and only dumbbells up to 50 lbs. Is it worthwhile for me to do some extra work on a muscle group in the evening with barbells after I've done my earlier workout in my work gym (say doing squats after legs at the work gym or barbell bench press after chest)? Would I be better off doing the gym workout one day and doing the barbell workout on another day after some recovery time?