How to lose weight for a teenager? -

im 16, 5ft 4inch, weigh 9st and am a male.how many calories should i be eating every day?i do athletics 4 times a week and am quite healthy (ie hardley any junk food)also what kind of exercise should i do to lose some wieght?i would like to lose between half a stone - to a stone

Try the lil Jack workout http://www.youtube.com/watch?v=TKCGe2Ezr��

drink lots of water and run alot and go to the gym (: and work out and continue eating healthy food (: ( mostly fruits )