When you are starting a training program, you want to make sure that you don’t increase your mileage too quickly. This also applies to runners that are coming back taking time off from their running. You want to increase your weekly mileage by no more than 10% from one week to the next. For example, if you are running 10 miles this week, you only want to run 1 more mile the next week.
You also want to make sure that you are giving your body time for rest and recovery after hard workouts. A rest day can be a complete day off, a day of easy and less miles or it can be a day of cross training. Cross training can be a nice walk, strength training, cycling or swimming. Whatever works for you, make sure that you are giving your body days to recover after a hard workout. This will also use different muscles than your running muscles, which will in turn make you a stronger runner.
Another way to help with overtraining is to give yourself a week of rest. Now, I don’t mean take a week completely off. Every 4 weeks or so, when you have been working out hard, give yourself a week where you do about 50% of your usual mileage. This gives your body (and mind) a rest. And, you’ll be surprised how much a rest week will refresh you.
To help with possible overtraining, there are a couple of more things that you need to do. Make sure that you are getting enough sleep. The amount of sleep each person needs is different, but you need to make sure that you are getting the amount your body needs for peak performance. Also, make sure that you are eating correctly. You need to replenish the calories that you are using during your runs. Remember a general rule is to have 60% carbs, 25% fat and 15% protein. This will make sure that you are refueling adequately.