Just how long should my long run be?

Probably one of the most common questions I hear as a running coach is about the long-run and just how long that should be.

When it comes to training for endurance there is always the unavoidable challenge of building up your mileage. There’s a lot more to it of course, but if you’re working towards a half marathon, marathon or even an ultra, the fact is that you need to run longer as you train.

But fear not, because it’s not just a case of piling mile upon mile until you seem to be spending more time out on your feet than you do at home. Like everything, there’s a hard way and a smart way.

Whilst like most things in running, it depends on the individual and the event, here are my general top-tips on building up your long-run training:

Focus on overall training load

The key is a gradual and consistent increase in overall training load. That means not just thinking about your ‘Sunday long run’, but the total volume of running done over a week. For some of us it’s hard to build the ever-increasing long run in to family life, so splitting your mileage up into a large number of shorter runs can work just as well as one single long run. And it's this consistency in mileage that will pay off in the long run, rather than single big-hits.

Slow and steady increase

The secret-sauce to this gradual & consistent increase is no more than a 10% increase week on week. And that goes for both your total weekly training load and your longest run. You need to allow your fitness and your strength to develop to take the additional miles, and increasing too quickly will only lead to injury and fatigue which will set you back - look out for an upcoming post on the importance of strength training to support mileage.

Time not miles

For many people it is better to think about time-on-feet rather than miles. If you set your long run based on how long you’re going to be out and how hard you’re going to run, then as your training progresses your increased efficiency means you’ll run further anyway because of pace as well as time. But this approach will take account of your fatigue levels, the terrain and even the weather, and avoid you busting a gut to hit an arbitrary mileage target that might prove a step too far.

2.5 hours max

I honestly don’t think you need to be out on your feet for any more than 2.5 hours at the most for a training run – and you probably shouldn’t. More than this and the extra benefit you get in endurance is balanced out by the additional recovery time needed. And that goes for any distance! For advanced marathon runners or ultra-runners, you may build in some double-run days, but anything more in training is for the ego and not the body.

Take a break

Neither the body nor the mind can take a constant increase in training week-after-week for ever. So build in regular drop-down weeks where you decrease your training load. I personally like to go for one in every four, where every 4th week both the total training load and long run go back to the level in the 1st week of that block, before continuing your upward curve again.

Plan backwards from race day

Mark your race day on the calendar, allow for a 2-week taper, then mark that date as your training end-date - NOT race day. Instead, that should be the date of your longest run/biggest training load week. Then work out c10% drops in weekly training-load and long-run back to today’s date (allowing for your drop-down weeks of course). This will tell you if you’re where you need to be now for that event target to be realistic, as well as forming the backbone of your training plan.

Then just stick all those things together, and your long-run/training-load training plan should look something like this:

Follow these simple few rules and you should find the build-up of miles/hours of running come relatively easily and hopefully injury-free!