I'M twenty years old turning 21 in a few months. I had my son early january so he is almost seven months now. I breastfed him until now but by the end of this month i am planning to put him onto formula. Since i have had him i have been really lazy and eating a lot of junk food but i'm planning on starting a diet and exercise as of next month. Before i got pregnant i had a reasonable tummy , when i would tense it there would be no excess fat hanging off like it does now. I want to know what types of excersise i can do to tone up my tummy. I hear people say ab crunches alone is not good enough and you need to do cardio as well. I got a few stretchmarks towards the end of my pregnancy which suked but i'll live. I want to know what are the chances of me having loose skin after i drop the weight off. I am 168 cm or 5'6 and currently weigh 70 kg or 154 pounds...a bit much lol