Understanding The Recovery Run and Why You're Probably Doing It Wrong

For any runner looking to improve, whether that means to get faster, run more consistently, log more miles, etc., recovery runs are a critical part of a training cycle.

"10 mile recovery run in the books! #trainhardrecoverharder"

Ever seen someone post anything like that on social media?  My response - You're doing it wrong.  And that is part of the reason why I am inspired to write this.  Too many people are putting their health at risk by failing to understand the recovery run and how it fits into the bigger picture.  And worse yet, logging miles of useless running doesn't lead a runner any closer to achieving a given goal. So let me lay it out for you to understand the what, why, and how.

But before I get there, let's take a look into better understanding some basic terminology before jumping into the specifics.  When we speak about run training in general, there are really two key terms to think about: stress workouts and recovery runs.

• Stress workouts: These are what we think about as the hard part of training - tempos, intervals, long runs.  These workouts target different energy systems to directly stress you and ultimately increase your fitness.  The specific stress workout to do, largely depends on what race you are training for and where in your training cycle you are in relation to your goal race.
• Recovery runs: As noted above, these are the "other" runs you do that support the work you do when you execute a stress workout.  All training programs (regardless of race distance) should incorporate recovery runs.  More about recovery runs can be found below.

The stress response model for general adaptation is a concept familiar to any sport.  The simple explanation is that in order to improve, we must first stress the system, followed by a period of recovery, followed by supercompensation, which makes us more fit. Following a stress workout, the body needs to recovery prior to adding another new stress, otherwise one would continue to build fatigue.  The result of too much of this fatigue is typically injury.  If you're lucky, your body shows signs before injury hits, but those that push beyond their body's signals often end up with some sort of injury.  Therefore, this cycle teaches us that when we place a stress upon our system, we need to allow adequate recovery so that we can continue to build up stronger and reach new levels of fitness as we train toward our goal race.

You might be wondering, well if recovery is so important, why not just take every day after a stress workout off instead of a recovery run?  Well there are multiple reasons why one should not necessarily take a day completely off after a stress workout.  I'll cover them in a moment below. 

So with those two general concepts clear, its important to understand why recovery runs are still important to every runner and how you should customize your recovery runs to meet your specific needs.  No matter what distance race you are training for, recovery runs serve the same purpose:

• To build volume of your running program and increase aerobic efficiency: Easy runs provide a safe means of adding volume to a runner's weekly mileage.  Running higher volume enables the ability to increase ones aerobic efficiency.  If you only ran stress workouts and took off every other day, it would only lead to 2-3 days of running per week, thus minimizing your ability to increase your aerobic efficiency (ie via too low volume).  Lots of easy running provides a safer means of accomplishing this and the more efficient you can become, the faster you can run at given intensities.  Further, the increased volume often provides a greater base of support to handle higher stress workouts, which can lead to even greater adaptations.  In other words, it allows you do to more, which can make you more fit.  
• Promote moderate bloodflow: While we hopefully all recognize now that the lactate, commonly associated with stress workouts, isn't the evil it was once thought to be, we also know that movement heals through bloodflow throughout the body to help remove toxins in the blodstream.  This is one of the benefits of massage and other similar therapies - to encourage bloodflow, which aids in recovery. Easy recovery runs enable you to promote bloodflow without causing much added stress.  The key here is to limit the amount of stress by keeping the run easy and relatively short (more on that in a bit). 
• Allow your body to adapt to the stress placed upon it through workouts: As noted in the adaptation diagram above, if you don't allow for sufficient recovery, you'll never reap the benefits of supercompensation to achieve higher levels of fitness.  Simply put, you'll be digging a hole you can't get out of through higher and higher levels of breakdown and fatigue.  So we do recovery runs to provide the limited stimulus, while still allowing our bodies to adapt.

So for all of these reasons (and probably many more I didn't include), it should be clear what recovery runs are, and why we should incorporate recovery runs.  But let's talk about how.

Like every recommendation/training principle, these are general guidelines.  However, the vast majority of runners could benefit from following them.  If injury statistics of runners are any indication, runners simply don't follow enough of these general guidelines.  So my advice is to simply follow it if you want to be able to train consistently.  So you want to know what the rule is?  Its pretty simple:

Each recovery run should be no longer than 10% of your weekly volume

Lastly, we all know that recovery runs should be done at a slower pace, but by how much?  I typically leave this up to how I'm feeling, but in general, it should be no more than 65-75% of your max heart rate or about 90 - 120 seconds slower than your 5k pace.  So combine the two guidelines of distance and pace and you've got a recipe for success.

Putting this all into context, this means that someone who runs 40 miles/week and has a 5k time of 25:00 (8:00/mi pace) should run no more than 4 miles per recovery run at between 9:30 - 10:00/mi.  So that 8-10 mile "recovery run" you just did wasn't much of a recovery at all.  In fact, you just created new stress on your body, which will carry over into your next stress workout and could potentially spin you down through the fatigue back hole.
 
Am I being a bit over dramatic about the impact?  Possibly, but consistently breaking this guideline will not lead you in the most direct form of progression and may very well result in injury.  So while doing this every once and a while isn't likely to have this impact, it may.  So take this advice for what its worth - another guideline to keep you injury free and constantly progressing as a runner, no matter what your goals are.