Benefits of Running Twice per Day

Runners often talk about “doubling” during training, particularly competitive athletes.  A “double” occurs when a runner completes two runs during the same day.  Think this is crazy?  There are actually numerous benefits to doubling, which will be described here. 

Benefits of Doubles

Training Adaptations
The purpose of training is to force your body to adapt to stress, such as glycogen depletion and minor muscular damage.  After you reach a certain threshold in your training, typically 55 – 60 miles per week, you may hit a plateau in your development.  Incorporating doubles can add more stress to your training load, allowing you to once again reap the benefits of cardiovascular and muscular adaptation. 

Enhanced Recovery
On a recovery day, what sounds easier?  One 8 mile run, or two 4 mile runs?  When properly spaced apart, completing two 4 mile runs can improve your body’s ability to recover from a hard or long run the previous day.  Additionally, studies have shown that the body produces recovery enhancing hormones in the first 10 – 20 minutes of a run, so doubling allows you to receive this benefit twice. 

Safe Way to Increase Mileage
If you are planning to increase your mileage, consider doing so through doubles.  Adding 5 – 10 miles to your weekly total is much safer when 2 – 3 short runs are tacked on, instead of one longer run.

Better Fit for Busy Schedules
Perhaps the only times you can run throughout the day are first thing in the morning, during lunch, or immediately after work.  Maximize the amount of time you are able to sleep by breaking your mileage up into two shorter runs. 

Tips for Doubling

Keep it Easy
When you begin to incorporate two runs into your schedule, make sure to keep the effort light and easy.  In the beginning, opt for 2 – 4 miles at recovery day pace. 

Plan runs 4+ Hours Apart
Ideally, your two runs should be spaced at least 4 hours apart.  The only exception to this rule is when you are opting to break your long run up into multiple segments.  Here, it is best to complete each component as close to one another as possible, in order to get the mitochondria-building benefits of your high mileage day. 

Incorporate “shake outs”
One of the best ways to bulk up your mileage while incorporating doubles is to add “shake out” runs to your schedule.  These are short and easy “junk mileage” runs typically completed a few hours after a race or workout.  Alternatively, you can run a morning shake out, which is 10 – 15 minutes first thing in the morning in order to get blood flowing and relieve stiffness in muscles and joints.