Whether you’re just starting out or are a seasoned runner, knowing how to safely increase your mileage can help you avoid injury. Do too much too soon and you’re more likely to be sidelined because your body isn’t ready to handle the increased miles. Wait too long between jumps in volume and you may feel like you’re not making enough progress.

So let’s say your baseline mileage is 20 miles a week. How do you increase this without increasing your chance of injury?

Many runners follow the 10 percent rule. The rule suggests that you not add more than 10 percent to your mileage in any given week. Although designed to help avoid overuse injuries, the rule doesn’t take into account differences in where you are in your training plan or how you feel, so it’s best to adapt this rule depending on circumstances. Here are some things to keep in mind:

Getting to your baseline. When you’re getting back to training after a break, begin below your baseline, say 12 miles a week. Since you’re not starting from scratch, you can usually add mileage more aggressively than 10 percent per week. So instead of adding just 1 mile a week, 1½- 2 additional weekly miles may be doable.

Pushing past your baseline. Once you’ve reached your 20 mile baseline, it’s time to be more conservative in adding mileage, aiming for 5 – 10 percent per week. So, you’ll still want to keep your weekly mileage increases to around 2 miles for the next few weeks.

You’ll get there if you’re patient. It may not seem like you’re making much progress adding 10 percent a week, but before you know it, you’ll be doubling your mileage. If you start at 20 miles, then go to 22, 24 and so on, within just 8 – 10 weeks, you’ll be running 40 weekly miles.

Splitting up your runs. You also have to determine how you’ll get in your weekly mileage. For example, if you’re running a total of 35 miles and run 5 times a week, you can do a 10 mile long run, 8 mile medium-distance run, 7 mile tempo run and then two easy 5 mile runs. Most mileage increases will add to your long run but sometimes you’ll want to split them up during the week.

What you do between runs. It’s important to alternate hard running days with recovery or rest days. Reduce mileage or intensity on those days or incorporate cross-training activities, such as cycling or weight-training. Some days, just do nothing.

The “less is more approach”. Some runners find they can get race-ready with less overall mileage by replacing 1- 2 moderate-paced runs a week with HIIT (high-intensity interval training) workouts. HIIT relies on relatively short intermittent bursts of running at very hard effort, followed by short periods of recovery.

Adaptation and recovery weeks. Some weeks you need to give your body a chance to adapt to mileage increases. Occasionally repeat the previous week’s training plan or give yourself a break every 4 – 6 weeks by cutting back on total mileage, shortening long or tempo runs, or running fewer days during the week.

Becoming a better runner isn’t about pushing yourself to increase mileage week after week according to a set rule. Instead, focus on running consistently. If you increase mileage too quickly or get to a point where you’re running more than your body is comfortable with, you increase the risk of overuse injuries, which can put the brakes on your training altogether.

Sources:

http://running.competitor.com/2015/07/training/a-smarter-way-to-increase-running-mileage_132282

http://www.active.com/running/articles/how-to-increase-running-mileage-safely

http://strengthrunning.com/2010/06/how-to-increase-mileage/

http://www.runnersworld.com/running-tips/the-10-percent-rule

http://running.competitor.com/2013/12/training/high-intensity-interval-training_58930