Splitting Up A Long Run In Marathon Training

woman running through woodland taking a selfie

I’m writing this sitting in bed after calling my final long run of marathon training at 10 miles. It had been going so well, I was charging along at race pace (naughty, long runs should be slow slow slow) and generally feel great, the crash. I hit the wall. Running into St James park all I wanted to do was go to sleep. It was horrible.

I didn’t want to stand any more. My head was light. My hip - close to where my c-section scar ends - ached. I got to a bench and called Mike. He spotted the problem immediately - I was under fuelled. All I’d had for breakfast was an espresso and half a bagel with peanut butter. Last night I only had a small bowl of pasta, and yesterdays lunch was non existent. That was far from enough for a 3.5hour run.

We talked through next steps. It wouldn’t be smart to risk pushing through 3 weeks out from race day, instead I’d come home, rest, refuel and head out in the evening to get the job done. And that’s exactly what I did. After a few hours of rest and recovery I headed out and ran 7 more miles with good form at a solid pace!

Why Split Up A Long Run

There are all sorts of reasons to split up your long run. Perhaps you’ve got a busy schedule and don’t have time to spend hours on the road in one go, or you’ve got a history of injuries and splitting up your run means you’ll maintain your form and reduce the risk of harm. Pushing through can lead to all sorts of aches, pains and potential injuries, which could seriously derail your training. Splitting your long run can also be helpful if you want to get a little more practice in running at race pace, or even to cover a few extra miles.

How To Split Up A Long Run

Breaking your long run into two segments in a day means you get the benefit of a recovery period and can run the last 30 or 40% of your long run with fresher form.

When I decided to split my run I had 1.5 hours left of my 3.5 hour run, so serendipitously it was a pretty perfect split. In the past I’ve done things like run from home to the start of a race, raced and then run back home or I’ve run to work and then home again (eating my way through all the office snacks between the runs, obviously!). Veteran marathoner Ian Thompson reportedly broke his long run into three chunks - in the morning he’d do an easy run, around midday he’d take on a structured speed session and in the evening he’d do another easy run.

Getting The Most Out Of A Split Long Run

If you’re going to split up your long run it’s worth thinking about how you’re going to get the most out of it:

  • make sure you make the most of your recovery time! When I split my run I came home, put my feet up and ate cheese toasties.

  • aim for your first run to be longer and slower than your first run

  • focus on maintaining form, especially during your second run when your legs will be fatigued

Why Not To Split Up A Long Run

In a perfect world you wouldn’t split up a long run - there are so many benefits for your brain and your body of clocking up those long miles all in one go:

  • you learn how to overcome the mental barriers that come with long distance running

  • you learn how to pace yourself more effectively

  • you learn how to fuel effectively

  • your body learns to adapt to the specific stress of long distance running

The Bottom Line

As I’ve said, in a perfect world you wouldn’t split up a long run, but life - and especially marathon training cycles - aren’t perfect! Sometimes you won’t have time to be on the road for endless hours, or you’ll have a niggle you don’t want to risk developing into an injury, maybe you’ll even mess up your fuelling and need to change your plans! Whatever happens don’t worry if you need to split up your run, it’s could be exactly what you need.

 
Splitting Up A Long Run During Marathon Training - Bethan Taylor-Swaine, London Running and Wellbeing