Why do I not need to run more than 20 miles in marathon training?

Not all training plans are the same & long run distances on a marathon plan can vary, but how long should your longest run be of the marathon block, & what determines this? At Coopah we recommend your longest run is no more than 20 miles, or 4 hours of running, & here are some reasons why…

increased injury risk

At Coopah we want you to reach the start line healthy, recovered from your peak weeks of training, & ready to take on your race.

Running beyond 20 miles brings a higher risk for developing injuries, burning out & peaking too soon. The 20 miler distance gives the opportunity to test fueling strategies & race day kit, in addition to allowing you to build enough endurance for the marathon distance without risking fatigue & exhaustion.

When it comes to running more than this, the injury risk outweighs the benefits. We don’t want you to be adding mileage out of fear that you’re not running enough, as you may end up doing your best running during training, & not race day when it counts.

THE NEED FOR RECOVERY

Pushing your body for longer than 4 hours or further than 20 miles can have a significant impact on how fast your body can recover & be ready to run again.

Coopah advises taking a rest day after your long runs due to the increased exertion of these sessions. You should still be able to complete runs in the coming days or weeks, & not have pushed too hard on one long run that you’re unable to continue training. If you exert your body to an unsustainable limit or distance your body won’t recover in time, meaning you may need to skip sessions on the plan or take additional time off to rest.

The marathon block should be a progressive overload, which means you are running on tired legs & increasing mileage up to your peak weeks of training, before you begin to reduce mileage & enter the taper period prior to race day.

During training we aren’t looking to fatigue the body to the point of exhaustion where there isn’t enough time to allow for appropriate recovery in readiness for your next training run, or even your race.

I FEEL AS THOUGH I’M NOT DOING ENOUGH

“How will I be able to run those last 6 miles if I’ve only run 20 in training?” This is a common thought, as many runners mentally feel they need to hit that milestone & run close to the marathon distance before race day.

It can feel reassuring to know you can reach this mileage, however, your mind will carry your body through those last 6 miles. Practising pacing in your training over consecutive weeks will help considerably when reaching those final miles of the marathon distance. Remember your 20 mile long run is completed as part of a peak mileage week, on already tired legs. Come race day, your 26 miles are completed on rested legs in a race environment!

If you find you are struggling to get through your long runs, you may be running at an unsustainable pace & should consider slowing down slightly… Download or open the app and chat to a coach for further advice!

Previous
Previous

Why run interval sessions when training for a marathon?

Next
Next

What if I didn’t get a place at the 2025 TCS London Marathon?