Nobody can tell you precisely how many miles per week you need to run to successfully complete your first marathon or half marathon. Every runner is different as are the individual goals and levels of ability.
But one of the most important questions any runner—regardless of experience—must answer when training for the marathon is how many miles per week do I need to run? The key is finding the optimal level of miles per week that will allow you to start the race as fit–and healthy–as possible for the always formidable 26.2-mile challenge.
Finding the right number of miles is different for everyone as is the buildup to that level. So, too, are the differences in training programs. Some programs advocate higher mileage totals than others, while others limit the miles and number of long runs. But, the more experienced runner you are and the more advanced you are in your training with more ambitious time goals, the higher your mileage generally will be.
There is simply no substitute for the mileage you must put in. (It doesn’t matter whether you keep track of your running by actual mileage or time spent running, but for the purposes of this article, we’ll stick with miles.) You can’t effectively run a marathon on the same amount of casual training you may have been doing for 5-K’s.
Miles are important to a marathoner because they produce essential returns in strength and endurance. The marathon is not a speed event. It’s an endurance race. The more miles you run, the stronger and more efficient you will become—but only to a point.
As the eminent exercise physiologist Dr. David Costill of Ball State University says, “There is a point of optimal distance that will cause the body to adapt to its full aerobic capacity. Based on laboratory observations, we have concluded that the mileage needed for the maximum training benefits varies between 60 and 90 miles per week.”
Whoa! That’s a lot of running, but Costill is only speaking about top-level runners who want to run three hours or faster. For less experienced runners who are mainly concerned with finishing the marathon or half, weekly mileage limits typically don’t exceed 50 miles.
That’s still plenty of running. But for most first-time marathoners, weekly mileage should vary between 30 and 40. If you’ve gradually built up to 30 or 40 miles per week from 15-20, this will have a huge impact on your fitness.
What the higher mileage does—even 30 to 40—is it trains your body to become more efficient at burning fat for fuel and spares the glycogen (key to marathon success) as long as possible. Equally important, it increases your aerobic capacity and builds mental and physical strength. There are other important physiological adaptations that take place with higher mileage as well as a reduction in body fat percentage and possible weight loss (though not necessarily).
But in the marathon it all comes down to developing the ability to endure. It is such a long event that more training miles is simply better than fewer miles. But again, more is only better to a certain point. There are diminishing returns with higher mileage and the more miles you run, the greater the risk of injury.
For first-time marathoners, who are targeting fall/winter marathons such as Austin, San Antonio, Dallas, College Station, Sacramento or Houston and currently running between 10 to 20 miles a week, they should plan to eventually boost their weekly mileage totals to 30 to 40. Mid-mileage runners, currently running 20 to 30 miles a week, should plan to up their weekly mileage totals to 40 to 45 miles per week. For those advanced runners who are normally running 40 miles per week, they should up their weekly mileage too, but only slightly as they will get limited benefit to going up to 50 to 60 miles per week.
These weekly mileage totals will vary during the course of your training training. Some weeks will be lower, but never higher. These are maximums.
In addition, most marathon training programs advocate that the longest training run of the week should be approximately one-third of the weekly total. So as the distance of your long runs goes up, your weekly mileage totals will too. But to keep the mileage from getting too high (and thus, potentially injurious), most programs factor in more rest days sandwiched around the long run as a safeguard.
Here are sample training weeks.
For low-mileage runners moving up to 30-40 mile weeks:
Sunday: Long run of 10-12 miles
Monday: Rest day
Tuesday: Easy five or six-mile run
Wednesday: Speed day of about six miles
Thursday: Easy five or six-mile run
Friday: Hill workout or fartlek of six miles
Saturday: Rest day
Total: 34 to 36 miles
For mid-mileage runners moving up to 40-45 mile weeks:
Sunday: Long run of 12-15 miles
Tuesday: Easy run of six or seven miles
Wednesday: Speed day of about six or seven miles
Thursday: Easy run of 8-10 miles
Friday: Hills or fartlek of six miles
Total: 40 to 45 miles
How to increase your weekly mileage safely:
1. Do it gradually. Build up your weekly mileage by adding a few miles (less than five) a week to your total. Since your weekly mileage depends largely on how many days a week you are currently running, the easiest way to increase the miles is by adding a day or two per week of easy running.
2. Maintain the effort, but lengthen the runs. Add a mile or two to each easy run and a similar amount to your weekly long run, but keep the same pace (or effort).
3. Don’t increase your weekly mileage week after week. The following two weeks after an increase, either maintain that same weekly level or lower your weekly total for a week.
4. Seek out soft surfaces for occasional runs. Since you’ll be increasing the time you spend on your feet, try to run on Butler/Lady Bird Lake Trail or grass soccer fields of Zilker Park once or twice a week to give your legs a break.
5. Don’t try to make up miles. If you miss a workout or cut one short, forget about it. Don’t try to make it up with an unscheduled run. It’s only one run, one week and in the big picture, it won’t matter if you fall short periodically on your weekly mileage goal.
6. Higher mileage shouldn’t be the goal. The reason you are running more miles is to get stronger for the marathon. That’s the goal—not humongous weekly mile totals that you put in your training log. If you find yourself overtired while running the higher weekly mileage, cut back. It may be too much.
Long runs are the toughest aspect of marathon training. Especially for beginners. But long runs are essential to marathon success.
Here are tips to make the weekly long run easier and boost your mileage:
1. Take walk breaks. Take your first break after the very first mile, even though you won’t be tired. Walk breaks will preserve your legs and also give you the opportunity to hydrate and take energy gels.
2. Start slow, finish strong. You should start off two or three minutes per mile slower than your expected long-run pace. That way you can finish strong.
3. Increase long-run distance by about a mile per week, but no more than two miles. Don’t try to make a huge jump from a long run of say six miles to one of 12. Be patient and build your endurance gradually.
4. Do long runs with a training group. It is much easier to do long runs and run the proper pace with a group of runners who are approximately the same level of ability. Don’t try to do long runs with a group of faster runners. It will be too hard.
5. Find your proper long-run pace and stick with it. There’s no big advantage to running long runs faster than what is prescribed so don’t. Stick with the training plan.
6. Alternate weeks. Once you get over 12 miles on a long run, do long runs every other week.
7. Target 20. The longest run first-timers should do before the marathon is 20 miles. But 18 is fine. Don’t attempt to go beyond 20-21. Most advanced marathoners usually don’t go past 22 or 23 miles.
8. Hydrate and take nutrition on the run. It is crucial you drink on long runs and you should also take energy gels. Practicing drinking and eating on the long runs during is great practice for the marathon. Experiment with different drinks and gels to find the ones that work best for you.
9. If you’re running Austin, practice long runs on the marathon course. Break the course up into manageable chunks and do some of your long runs on parts of it. Most of the toughest hills are in the first 10 miles but there are some sneaky hills near the end. So try and include a few hills near the end of your long runs. Under no circumstances, try and run the entire course in a single run. Save that for February 15th.
10. After finishing, walk. Do a proper cooldown by walking which will allow you to walk off some of the stiffness that may occur. Later in the day, go for another easy walk.