What is the shortest training run that will improve your fitness?

I often hear runners say that they missed a run "because I only had enough time to do 5km and it wasn't worth it" or "I won't lace up my shoes for anything less than 10km"

I am a huge believer in the "little and often" philosophy. I think it can be applied to a lot of aspects of life, especially running. Another way to think of it is "sub-threshold" training, meaning that you should train well below your body's exercise threshold (capacity) most of the time.

Let's use chin-ups as an example. Imagine you want to be able to do 10 chin-ups in a row, but you have only recently started on this quest and you currently find it really hard to do 5.

So - you start training by doing 5 reps. It hurts, but you manage it. The next day you do 5 more, and the day after that another 5.

But now your shoulders hurt, so you need a day off. The next set of 5 causes the pain to flair up again . . . any more sessions in the near future and you are going to have a shoulder injury to deal with.

A safer, and ultimately more productive way of training for the 10 chin-up challenge would have been to start with just 1 chin-up, but repeat it perhaps 3 times over the course of a day, and then keep repeating that until it becomes easy. After a week or two you could progress to 2 chin-ups 3 times a day, or 1 chin-up 5 times a day.

Before very long at all, you would be doing more chin-ups in total, with a lot less risk than trying to squeeze out a single set of 5 each day.

This "little and often" approach would be a much more sustainable method of training for your goal.

How does this apply to your running?

We'll use marathon training as an example, but the same philosophy can be applied to someone training for a run of any distance whether it is 3km, 100km, or anything in between.

A marathon is 42.2km, so it might be hard to see the relevance or benefit of an easy 3km training run. But every run counts. Over the course of a 16-week marathon training plan, if you "snuck in" 2 x 3km runs per week instead of taking a day off because you "didn't have time to train" - you would have added nearly 100km of running to your total training volume.

If your training plan averaged 70km/week for those 16-weeks, then these little 3km runs would add up to nearly 10% of your total training volume. That is significant.

Every Run Counts

Every training run you do without injuring yourself will improve your overall running efficiency, strength and fitness.

Training well below your body's threshold will be more sustainable, allowing you to train consistently with much less risk of injury.


So, instead of missing a training day due to a lack of time, or thinking "I'll do twice as much tomorrow to make up for it" - put on your shoes and get out the door whenever you possibly can. Even for 10 minutes if that is all you have time for. It will be good for your brain, good for your cardiovascular health, and beneficial for your training goal.