First off, I just want to say that lot of people do not start running until after college, so if you think you are "behind the ball" a bit, you are not! Anyone at any age and virtually in any "shape" as far as exercise is concerned can train and run a 5k. And it definitely helps to have friends who are also interested in running! They can easily become your best support group and team of encouragers, and running with friends either just for fun or in a race can be a great experience!
If you are looking for some 5ks to run, or for a great training plan to follow to help get you into shape, you have come to the right place! Check out our list of 5ks you should run, and here is a 6 week guide to getting you ready to run a 5k.
The rule of thumb for beginners is to start slow. If you run too often, too fast you will likely just end up injured. Start by making it a goal to run a couple times a week, but not consecutive days in a row. And pick a moderate distance to start! If you need ideas, try this: during week one, aim to run half a mile two to three days a week. Then the next week, aim to run one mile, two-three days a week. Continue increasing your mileage each week by half-mile increments until you're running 4 miles without stopping. That way, you can be sure that you can run the whole 3.1 miles on race day!
On the days you do not run, consider cross-training of some sort. You might want to cycle, swim, play another sport, or weight train. Building up your muscles and gaining strength really translates into better running form, and an overall less painful running experience. Also, be sure to hydrate correctly and get enough water (as well as quality nutrients!) in your body as you start to run more.