How long do i need to run to burn fat?

Question

I'm 5'4 and 117 pounds... i realize that i have a normal BMI but i would like to have a tighter stomach. I'm combining running and ab exercises but i was wondering how long it takes until your body starts burning the fat and not just the available sugar. I run maybe an 8:30 mile so thats not bad i guess and im trying to get into shape for a half marathon. Also, if i run 6 days out of the week for over half an hour, how long will it take for me to see the results? If you see the women at the olympic trials and how tight their abs are... i want that. How long do i need to run and whats the most effective ab exercises that i can do to see results faster? Thanks!!

Answer 1

Is your question related to how quick can you lose weight or how can you get more defined abs (or both)?  If you want to know how much fat you are burning, you can estimate that you burn 100 calories for every mile you run.  You have to burn about 3,500 calories to lose a pound of fat.  So, you can do the math on that.  If you want to have great abs that you can see, then you also have to do a lot of ab exercises, and I am not talking 10 sit ups.  Think in terms of a 10 to 15 minute ab workout every other day...say 100 full situps, 100 bicycle crunches etc.  You can throw  in some pushups also...for your arms and your abs, if you are doing them right.  And of course, you have to be pretty slim to see the abs, depending a bit on your body type.  Remember, all this exercise is going to make you hungry.  A half a cup of Ben & Jerry's is about 300 calories.  So, you can eat the calories you have burnt in a half hour run without even noticing.  Make sure you are not increasing your calorie intake if you want to lose weight.  In fact, for effective weight loss, you will probably have to decrease what you eat, while you exercise more. For getting into shape for the half marathon, there are a lot of sites which have workout schedules, so you should probably try to follow one of those and be more precise in your mileage than "over half an hour."  I am not trying to discourage you; you seem in great shape already, judging by your stats,  and since you sound like you are relatively young, you should be able to look fantastic and run a great half marathon without too much pain!  :-)

Answer 2

You need to have a heart rate of over 120 typically under 150 or 160 for over 20 minutes.  Try circuit training and interval training with some long distance thrown in there.  Should be able to work out 4-5 times a week and have plenty of time for recovery.  Interval training can encompass 1 minute of running with 2-3 minutes of jogging for 30 minutes.  Circuit training would be 20-30 seconds of 15 different activities such as crunches, pushups, etc.  

Good Luck!

Answer 3

Well, this is said that and average person must have some kind of phisicle activety a day.  60 min. a day whould be great.  Each time you make a step, it is known you already burn a few calories!

Answer 4

Your body always burns some fat and some glycogen when you exercise.  It is really irrelevant what you burn during the exercise because weight loss is a function consuming fewer calories than you burn.  In your case, being 5' 4" and 117 lbs, you really don't need to lose weight.  

Running is mainly going to build leg muscles.  If you want to tone your abs then you need to train those muscles specifically.  Running alone is not going to do it.  Here's a link to some core exercises for runners you can try.

http://pfitzinger.com/cc.shtml

Finally, one thing to consider is that the women in the Olympic trials are professional athletes.  They are people with exceptional sports genes who invest a lot time in their training so you need to be patient.