This article gives you a flexible, fun, and above all, possible, way to go from flabby to 5K.
The following was advice written to a friend who was having trouble keeping up with an "ease into 5K" program, which was supposed to get her from flabby to 5K in eight weeks.
First, if you are having problems making progress in your fitness, see a doctor and get a physical! You can imagine that with my experience I would advise that.
If I were to try to get you to go "flabby to 5K" in 8 weeks, well, I wouldn't. I'd tell you 12 weeks. But if I were shooting for 8 weeks, here's the plan I would put you on. I suspect you'll find this a lot easier ... and more fun.
Let me tell you something about human beings. Humans suck at consistency. There are a few exceptions, but most of the people that you think are exceptions probably aren't. They are simply more committed to success and easier on themselves when they fail.
The route to exercise success is to keep at it. At your age, the gains you accomplish won't go away if you backslide for a week. You won't make any gains running once per week, but you will make gains running 5 days one week, then taking a week off. I don't recommend that plan, but knowing such a plan will provide some forward progress will take some pressure off you to be the consistent exerciser that very few people are.
If you can walk two miles, then do two miles five times per week. Run 1/4 of a mile each day that you do two miles. You can run the quarter mile in fifteen thirty-yard segments if you want or even twenty-two twenty-yard segments. Just shoot for a quarter mile.
Don't measure it; guess.
If you can't walk two miles, and you need to work up to that, see How to Start Jogging.
You also need to close to a reasonable weight (not scrawny, like American TV suggests, just reasonable). These great free diet tips will help. I no longer have control over that web site, but I did write that article.
And run at a ten-minute-per-mile pace, not thirteen or fourteen. Stretch those legs out and make your lungs work hard, but not for long.
Have fun. If you can't slip in ten fifty-yard "dashes" (at a ten-minute-per-mile pace, not a sprint) the first week, then don't. Do five. Or do two.
Get to where you can do that, and the fifty or hundred-yard "dashes" are fun. Get to where the hard breathing from doing that feels good.
When you are there, you've hit the starting point. Here's how to get to 5K within 8 weeks of that.
First Two Weeks
Move up to a half-mile of running in your two miles.
Second Two Weeks
Move up to a mile of running, and now cover 2.5 or 3.0 miles total. That gives you space to spread that mile out more and recover between your hundred-yard or quarter-mile segments.
Third Two Weeks
Move up to 1.5 miles of running, and make sure to do 3 miles total. You can even go up to 4 miles, but that's up to you. No need to consume your whole day, but sometimes it's easier to spread the running out across a longer distance.
Fourth Two Weeks
Move up to 2 miles of running, and make sure that you're doing at least two half-mile runs. Stay at 3 to 4 miles total unless you just really enjoy doing more. Even if you do more, don't obligate yourself to continue to do more. You could cover 5 miles in one day, then go back to 3 miles on your next jog.
After you do two weeks of running two miles and walking one to two miles, you'll be able to run a 5K even though you haven't done it. Slow down to a 12-minute mile run. You'll be amazed. Even then, don't be afraid to take a 100-yard walk several times. It probably won't even slow down your 12-minute-per-mile pace.
I heard of a guy who ran a 2:15 marathon walking one minute out of every ten. Do the math on that one! (2:15 will qualify you for the olympic trials in the U.S.)
Note that my prescribed 10-minute-per-mile twenty-yard dashes are breathing exercises. Later, the 10-minute-per-mile half-mile runs will be breathing exercises as well. There's no reason that you shouldn't be enjoying them by the time you get to them, not just tolerating them.
This plan should leave you wanting to do more every now and then, to press a little harder on a short run, to test yourself a bit. If that's not true—after you've reached that foundation I prescribed—email me.