Unfortunately in just about every aspect of running, there is no one direct answer to a running question. As I have discussed before, what works for one person may not work for another, whether it’s shoes, nutrition, recovery methods and even weekly mileage.
There are runners who run upwards of 100 miles per week, but another runner at that same caliber runs 75 miles per week. Why then does one person run more mileage if they essentially run the same race times?
Well, that is because one person’s weekly mileage “sweet spot” may not be another runner’s ideal weekly mileage. Runners need to take into account how their body feels after a high or low mileage week, and not all runners handle mileage the same.
One key point in determining your weekly mileage is considering the amount of time you have to build up your mileage before a key race. When someone asks me the question, “How many miles a week do you train?” or “How do I increase my mileage?” I always refer to my disclaimer first and remind people that mileage, like many areas in running, is very individualized. But there are some helpful ways to make a successful mileage increase.
Runners should consider the 10 percent rule, meaning you increase your mileage by 10 percent each week as you build up to your desired miles per week. Clearly, using this method can take a number of weeks to reach your desired weekly mileage, especially if you’re starting from scratch, but running enthusiasts believe the 10 percent rule is a conservative approach that’ll allow you to ease into mileage without getting injured and beating your body up from week to week. I agree this can be a great way to build up mileage cautiously, especially for beginners; however, this is not the only method that can work.
When considering a mileage increase, I continually encourage runners to be consistent in their training. If you're consistent with your training and focus on long-term development as a runner, this is where you’ll find your mileage sweet spot. I have found my mileage sweet spot to be around 50 miles per week - I get in quality miles without overdoing it, feeling overtired or getting injured. When I'd rack up more than 70 miles a week for key races, I found my body wasn’t able to handle that amount of mileage as much, so I’ve chosen to lean toward the quality of my training runs rather than the quantity.
By being consistent in your training you’ll discover how many miles a week you and your body can handle. The more experienced you get, the more in tune you’ll be with where your weekly mileage should be. This is all part of your learning process as a runner.
For example, if you've been running 3-5 miles per day four days a week and you’ve remained consistent in doing four running days a week for at least two weeks, maybe it’s time to tweak your training. If you decide to add in a fifth day of running that distance, or keep it to four days but increase your mileage by lengthening a run or two, you’ll increase your mileage without a huge risk of injury.
Maintaining a running log, writing down your new mileage and jotting down how your body is feeling, will also keep you aware of how the mileage change is affecting your body. If all is well, do another couple of weeks with that increased mileage, and repeat the process by making slight tweaks along the way. As long as you aren’t making drastic changes from one week to the next and you have remained consistent, your body will adapt to the change without feeling overworked, and hopefully you’ll remain injury-free.
If you train smart, pay attention to the little things and don’t make drastic changes along the way, you should find that increasing your mileage isn’t challenging. It’s just remembering to be patient.