ok heres the deal... i have been overweight ALL my life... NEVER excersized... i was just plain lazy.. never dieted just ate whatever i wanted to.. well the past week or so i have joined a gym... and started eating right, but heres the thing.. i see you guys talking about going for like a hour on the treadmill or eliptical machines i can go like 30 mins on a bike... but running ;x i get tired after a 2 mile walk.. so heres my question. is what im doing going to even have any effect on me?? since when i hit the gym im only burning like 300 cal. a day?(remember i never did any excersize or activitys before) i was thinking what i was doing was alot but reading some other post it aint shit... but thats all im able to do without passing out.. how long does it take for stamina to build up? it just really makes me feal bad.. im really motivated to loose weight but i tire so easy!!!!