Want to Run Longer? Don’t Skip These Mileage Rules

The time has come. You’ve run a few 5Ks and 10Ks, and now it’s time to tackle a half or even a full marathon.

Part of that new challenge is often running more—more weekly mileage and longer runs—but how do you run longer safely? You should approach increasing mileage and time running wisely to avoid injury, excessive soreness, and even burnout.

How to Run Longer While Staying Injury-Free

Throughout my decades in the running industry, where I’ve coached beginners to Olympians, I’ve found three main tenets of running longer safely hold true (whether you’re training for your first 5K or ultra marathon). Here’s how to safely build your running volume.

1. Outline Your Training Plan

In general, the more you run, the stronger and faster you become, but like a lot of things in running, it’s not as easy as it seems on the surface.

While your cardiovascular system adapts quickly to increased mileage, your musculoskeletal system (the muscles, bones, tendons, ligaments, and fascia) adapts much more slowly. That’s why runners can get injured a few weeks after boosting their mileage. They feel OK running, but the body is struggling to adapt to the increased load.

To combat this, you need to be smart about your mileage increase. And trust me, you need a plan for increasing your mileage. Otherwise, you have a high likelihood of getting injured.

The 10% Rule

Used for over half a century, the 10% rule says that you should not increase your weekly mileage by more than 10% per week. And I would add that you should only increase your mileage for two or three weeks in a row before giving the body some time to recover. More on that later.

Using the 10% Rule, if your current weekly mileage is 25 miles, then you can safely increase to 27.5 miles (25 miles x 10% = 2.5 miles) the following week. If you run 60 miles per week, the 10% Rule says you can increase your mileage by 6 miles the following week.

For lower mileage runners, most of the increase in weekly mileage comes from your training plan’s long runs.

In the Couch to Marathon training plan, you’ll notice an increase of 2 miles in the long run from week to week. That takes care of most of the mileage increase for the week for many runners. Then, if there is any additional mileage left to get to the 10% of your previous week’s mileage, you simply add this to one or more of your other weekly runs.

You can, of course, just add the same amount of mileage to each run equally to achieve the total increase for the week. For the mid and high mileage runner, the increase in mileage is often spread across a few runs in the week, not just the long run.

That said, my advice is that you never add more than 20-30 minutes to any long run, no matter if you are a low-mileage runner or a high-mileage runner.

Another strategy, particularly for runners who have maxed out their time availability on daily runs, is to add another day of running. Running more frequently (more days per week) can be great for performance, but you must closely monitor your body. You’re reducing the recovery time for your musculoskeletal system, so you must be even more vigilant to avoid injuries.

Caveats and Considerations to the 10% Rule

• Run/Walk or walk to add more mileage without extra stress on the body.
• If you’ve maxed out your time availability in your single runs during the week and still need more mileage, consider a second run on one or two days to boost mileage.
• Be open to adjusting the chase for mileage based on how you feel and your life schedule. Life happens, so be prepared that your planned mileage may not always fit into your life and that is OK.
• While we may love the structured plan to increase mileage, remember that this does not have to be every week. You might find that increased mileage every other week works better for you.

2. Pre-Schedule Down Weeks

Down weeks (also called deload or step back weeks) are one of the most important concepts coaches use to help runners stay healthy, especially as they increase mileage.

A down week is when you reduce your training load by 15-25% to allow the body and mind to absorb the previous training and be ready for the next segment of training.

Including a down week every third or fourth week across a training plan has dropped the injury rate of my athletes to nearly zero. And mentally, runners also love the rhythm of focusing for 2-3 weeks, then they get a mental break for a week before repeating the cycle.

There are a couple of ways to make a training week a down week.

First, you can simply reduce each run by 15-25%. Second, you can run one less day in your down week. It’s really the runner’s choice, so think about what you would enjoy more—a complete day off or just less running on some, if not all, runs in the week.

While the volume drops in a down week, I tend to like to keep some intensity just so you don’t feel sluggish. The volume of any of your faster runs may decrease, but maintaining the intensity seems to work well unless you are injury-prone. If injury-prone, then consider reducing both the volume and intensity in your down weeks.

Training fatigue can sneak up on you, and you want to head it off before it happens. Pre-planning down weeks and doing them even if you feel fine is the way coaches keep their athletes healthy and motivated for training.

3. Love Your Body

As you advance your training, it is critical that you stay injury-free. While a smart training plan and down weeks are essential, the other component is taking care of your body.

For my athletes, we break body care into three types—self-care, professional care, and strength/stability training.

Self-Care/Mobility

The most important self-care you can do is a mobility routine. While experts debate the benefit of “stretching,” I find that a simple mobility routine is the best diagnostic tool runners can use to find potential injuries.

Tightness is the body’s first defense against overuse injuries. You may not feel aches or pains while running, but as you go through your mobility routine, any area that is tight shows that you need to treat it and even consider a reduction in training.

Active isolated mobility is what I recommend for this self-diagnostic routine. These slow movements reveal tight areas, and once uncovered, it’s time to use all of the tools at your disposal to work on those areas.

Massage guns, foam rollers, and icing are great tools to use regularly to keep your body happy.

Professional Care

Sports physical therapists are geniuses at finding vulnerable areas in your body. Much like your mobility routine, regular visits to a sports therapist/bodyworker keep your body healthy and happy as you advance your training. Just make it a regular habit.

Therapists may seem like miracle workers, but you help them immensely if you see them at least once every two weeks. They learn your body, your vulnerable areas, and have the expertise to treat you and provide advice on training modifications—particularly related to stability and strength in your trouble areas.

Hit the Gym

Speaking of stability and strength, functional stability and functional strength are the twin pillars of healthy running. Luckily, for most runners, a little goes a long way to keep you healthy. (A lot goes even farther, but most of us are time crunched, so any stability and strength work you can do is of great help.)

When researching strength programs, look for exercises that are specific to runners. Single-leg stance, balance training, and core exercises are really helpful.

How Much Is Too Much?

That is the big question. In the past, runners would increase mileage till they got hurt to determine their healthy mileage threshold. I never liked that process, so I suggest taking mileage increases in small chunks each training cycle.

For example, if your usual weekly mileage is 30 miles per week, don’t try to go to 50 miles per week in your next training cycle. A 25-50% increase is more doable and less risky. Don’t get greedy, but know that even small increases in volume can make a big difference in your performance.

And remember, your maximum mileage is individual and may vary from year to year. But, if you follow a smart training plan, schedule reasonable increases in volume, take down weeks and, most importantly, do the things that head off injury, you will find that you can safely increase your mileage.