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Have you heard of the 10 Percent Rule for increasing your weekly running mileage?
Most runners have. It’s a nearly universally accepted way of boosting your training volume. It simply says that you should add no more than 10 percent per week to your total weekly mileage.
But this “rule” is flawed. There are many cases when mileage should be increased more aggressively—or much more conservatively.
Instead of blindly running 10 percent more every week, there’s a better way. Let’s learn how to build mileage more strategically, recover when necessary and boost your endurance at the same time.
There are three concepts to understand. Let’s get started.
1. Know Your Baseline Mileage
Your “baseline mileage” is the number of miles that you feel comfortable running every week. You don’t struggle or feel challenged at this level. Every runner has their own unique baseline mileage.
Figure out your personal baseline by looking over the last 4-6 months of training logs. What is the amount of mileage that you feel comfortable with? It’s not too easy or too hard. This is your starting point and most of your training cycles should start slightly under your baseline mileage to ensure you’re starting at a realistic workload.
The key to successfully building your mileage is to know when to aggressively build your mileage—and when to conservatively add miles to your plan.
When you’re building up to your baseline, you can increase your mileage more quickly than 10 percent per week. The miles are still very comfortable at this point, after all. You can safely add 15-20 percent more per week.
But as soon as your mileage is above your baseline mileage, it’s helpful to be more conservative. Rather than adding 10 percent per week, it’s best to add 5-10 percent every second week.
Understanding this concept will help you prevent more injuries and consistently run more volume over time.
2. Use “Adaptation Weeks” to Your Advantage
I use “adaptation weeks” with the runners I coach. It’s simply a repeated week of training—from the mileage to the workouts and the long run.
It’s helpful for all runners, particularly those who are prone to injuries or beginners who need extra time to recover from and adapt to their running workouts.
By repeating a week of training, you’re allowing the body to adjust to the increasing mileage and the intensity or longer duration of the quality workouts. Runners often increase mileage too quickly, so this measure ensures their training is more conservative.
But you don’t need adaptation weeks every week. When you’re building mileage up to your baseline, there’s no need to be this conservative. However, after you surpass your baseline mileage and you don’t feel comfortable, it’s more helpful to implement them.
3. Take A Recovery Week Every 4-6 Weeks
For those runners who love pounding asphalt and challenging themselves, this is going to be a hard pill to swallow. Periodically during your training cycle, the overall mileage and workout intensity should dip to allow the body an opportunity to recover and adapt.
For example, if you’re running 40 miles per week with a 5-mile tempo run and a 10-mile long run, a recovery week might only be 30 miles, a 3-mile tempo run (or other type of shorter workout), and an 8-mile long run.
Mileage decreases during a recovery week should be about 10-25 percent depending on how hard you’re training, your experience level and past susceptibility to running injuries.
Other variables to consider making easier are:
- Your strength workouts (instead of a challenging gym workout, try an easier bodyweight workout at home)
- The number of days you run per week (my suggestion is to reduce this by one, so instead of running 5 days per week like you normally do, just run 4 days during a recovery week)
- The number of faster workouts you run per week (for example, instead of two, just run one)
Of course, recovery weeks are only needed during hard training. If the volume of training is under your mileage baseline, there’s no need to implement a recovery week. There’s barely anything to recover from!
Instead, recovery weeks are best used strategically when the overall mileage of your program is more than what you consider comfortable. At this time, it’s best to be more conservative.
By knowing your mileage baseline, you can then strategically implement adaptation weeks and recovery weeks into your training. This is a smarter way to manage mileage than by blindly increasing training volume by 10 percent every week.
By planning your season this way, you’ll feel better, get injured far less frequently and ultimately race a lot faster!
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About the Author:
Jason Fitzgerald is the head coach at Strength Running, one of the web’s largest coaching sites for runners. He is a 2:39 marathoner, USATF-certified coach and his passion is helping runners set monster personal bests. Follow him on Twitter @JasonFitz1 and Facebook.