My subway sub had a total of about 40 grams of carbs... i'm going to the gym today.. but I want to know roughly how long does it take to burn off that many carbs? I don't usually count carbs or even pay much attention to them, but does anyone know?
Unfortunately, your question cannot be answered.
Carbohydrates, proteins, and fats all contain calories. Carbohydrates and proteins contain about 4 cal/gm, while fat contains 9 cal/gm. The major difference in these dietary nutrients is in their digestive pathway. Carbohydrates are generally the easiest to digest, leading to rapid rise in blood sugar. Proteins and fat take longer.
If your sandwich had only 40 gm of carbohydrates, that would be equal to ~160 cal (was this a veggie only sandwich, no cheese, meat, mayo?). You would need to expend 160 cal during your exercise.
Of course, the amount of calories you burn depends on the type of activity you're doing. A slow walk obviously requires less energy than a hard sprint up a 30 degree incline.
True. If you have a diet high in simple carbs then they are the first thing to go, and fat stores stay put. This is why diets like Atkins do cause loss of fat/weight. By avoiding sugar in all it's forms (high fructose corn syrup being the worst), stay away from all white stuff (bread, potato, rice, flour) you will start to burn the fat. If you take even a short walk after meals (10-20 minutes) the glucose in your blood will be use up and fat burning will increase. Go to MyPyramid.gov for a healthy food guide with complex carbs.
Carbs are coverted to sugar. The sugar in your blood stream is used during the first 30 minutes of a workout. The intense part of the workout (changing up a run with sprints after 30 minutes) will target fat stores.
It's difficult to know how much of the carbs will still be in sugar form