I lost about a stone in weight whilst splitting up with dh ( due to stress ), I would now like to keep it off and tone up. I have been going to the gym for a few weeks but mainly been doing cardio workouts ( treadmill, bike and rowing ), have just ventured over to weights to tone up my bingo wings but the main things I need to work on are my bum and tum, my bum is very flat ( probably from sitting on it way too much ). What are the best things to do to tone up? Are squats really good for your bum? Any advice please?