Q+A: How should I train for a 50K?

Q. In my time as a runner, I’ve run seven marathons, and now I want to train for an ultra-distance trail run of 50K (just over 30 miles). How should I modify my marathon training to prepare for the longer race?

A Assuming that your seven marathons have gone smoothly, the move up to 50K should be completely possible. The two big differences from a marathon will be: (1) you’ll be running for an extra hour or two; and (2) your race pace is likely to be significantly slower.

If you’ve trained and raced your marathons exclusively on the road, it’s essential that you do as much of your ultra training as possible on trails, especially your long runs (these will be critical to your success). Off-road runs are easier on your legs, but the rougher terrain can be trickier to navigate, particularly when you’re tired. Run while looking ahead, and stay alert for unstable footing.

The only other modification I’d recommend is to increase the length of your longest runs to 25-28 miles. As with marathon training, you should reach this long-run peak three weeks to a month before race day, then you can start to taper.

If this extra mileage seems too much for you, stay with the standard 18- to 20-mile runs of a marathon plan. After all, the 50K is only around five miles longer than the marathon distance. Do your long runs every other week, or every third week if it takes you longer to recover. Also, consider taking short walking breaks during your long runs, as this will help you recover faster.

Always run with a water bottle and practise eating during your runs (energy gels are a great idea). And remember to be conservative on race day. I recommend that you aim for a minute per mile slower than your marathon pace, especially if the course is hilly. Good luck!

Ric Munoz, veteran of 131 marathons and six ultras