In this article Trackstaa looks at the benefits of increasing mileage in a safe and effective way to optimise performance and mitigate the risk of injury.

According to recent research, elite British runners lose, on average, approximately 49 days per year of training to injury and so if you have picked up a niggle or injury recently, fear not because you’re not alone! Helpfully, we’ve published numerous articles across our website about how to avoid injury including advice on what you can do when the worst happens, with expert sports therapist, Simon O’Brien, which you can read here.

But what happens when you want to make the next step towards your running goals and increase your mileage.

Benefits of increasing mileage

For the most part, the more time you spend running the better runner you will become, it may seem trivial, but it can easily be overlooked, especially with regard to those easier miles. Here are just a few benefits of increasing mileage on a consistent basis.

Firstly, it is likely to improve your aerobic capacity as well as allowing your body to better manage your glycogen stores. This is because when you run your body burns through a mixture of carbohydrates and fat. As you continue to run and exert yourself your glycogen stores start to dwindle, and your body will start to use fat instead which as an energy source is 15% less efficient. Now, I’m aware this is all starting to sound rather scientific. But the result of it is that when you run low on glycogen you will start to fatigue, especially over the longer distances where your body needs a constant supply of energy.

Secondly, it helps improve your running efficiency, having your feet relentlessly pounding on the asphalt and your arms pumping like pistons will get your body used to the unrelenting toll running can take on your body; after all, practice makes perfect. However, this isn’t always true and if you are struggling with your form try specific drills or consulting a professional.

Finally, and arguably most importantly it builds resilience and mental toughness as the seemingly endless miles will prepare you for the inevitable fatigue you will feel during races. If you are consistently running 10km on your easy runs, a 5km race should feel like a walk in the park. The mind is incredibly influential when it comes to running at your best; training to enjoy running will give you a huge advantage on race day. The greatest marathon runner of all time (no bonus points for guessing who) often preaches that “no human is limited”, as he truly believes that the power of human resolve can break any barrier.

Slow and steady wins the race!

Okay, so slow and steady won’t actually win you the race but it is certainly the approach that should be taken when increasing your mileage. Many runners will stick to the 10-percent rule (10PR) which requires that you do not increase your milage by more than 10% on the previous week. For example, if last week you ran 50km this week you should run no further than 55km or if last week you ran 20km going far over 22km the following week could lead to some potential problems later down the line. This rule certainly has merit, however in some circumstances I would recommend being even more cautious, especially if you are a younger runner or a runner with a history of over-use injuries.

This is because although there have been successful cases of young runners having extremely high mileage weeks such as Jakob Ingebrigtsen who at 13 years was running at least 140km a week, this type of training is very easy to get wrong and can end with serious injury.

Furthermore, you should aim to keep your training balanced. What I mean by this is that a good proportion (approximately 80%) of your week should be easy miles see Figure 1 for examples of what suitable easy running should look like. This should hopefully keep you working at around 65% of your VO2 max for your easy runs (give or take 5%) which is enough to improve your aerobic fitness but shouldn’t push you into anaerobic respiration where you will start to produce lots of lactic acid.

Furthermore, if you are training to run faster and not just to increase fitness, it is important to do tempo runs, these are moderately paced at a pace you could just about maintain for an hour (around 15-20 seconds slower than your current 5k pace) so using the example in Figure 1 this should be 4:20 or so. Finally long runs are always a good idea and should make up approximately 20-25% of your weekly mileage. We have written a detailed article on the different training paces and how you can incorporate them into your training programme, which you can read here.

Figure 1

Strength and conditioning is absolutely vital!

The benefits of strength and conditioning (S+C) cannot be stressed enough and if there is one thing to take away from this article it is that increasing mileage and doing S+C should go hand in hand. While massaging and foam rolling can feel therapeutic and can be beneficial for getting blood moving around your muscles, their usefulness beyond this point is relatively limited. For the most part you would be much better off spending your time doing S+C than any form of massage. This is because proper strength and conditioning can allow a runner to strengthen supporting muscles, increase mobility and equalise any muscle imbalances which is invaluable in preventing injuries.

If you are worried you don’t have the right equipment or don’t have a gym membership, then fear not! There are plenty of bodyweight exercises you can do that simply require a little bit of open space, check out our YouTube video, with Ari Klau, on core exercises here, for example.

Having the right tools for the job

In the same way you wouldn’t use an F1 car to pop up to the shops and back (okay, I probably would if I could), you should avoid using fast, un-cushioned or carbon plated shoes for all your running. It’s tempting to use fast shoes for all your runs simply because they make you run faster, however, for easy runs especially I would recommend investing in a pair of very well cushioned shoes that you enjoy running in. Also, it’s a good idea to have a rotation of shoes that you can use for different things, for example a pair for tempo runs, a pair for speed, and a pair for recovery runs, for more detail on this check out our shoe rotation video and article.

Nutrition and sleep

When increasing your mileage, you will certainly notice that you are suddenly more hungry and tired, this is completely normal and nothing to worry about, in fact it’s a sign that your training is going well. However, it’s important to listen to your body, as often runners can misinterpret signs of sleep deprivation as training fatigue, it’s important to try and get at least 8 hours of sleep every night – it’s fundamental for health and recovery. We’ve written a detailed article on the importance of sleep, which you can read here.

Most importantly of all perhaps, is ensuring that you fuel your body properly. It is important in any stage of your training cycle but is crucial when increasing mileage as you have to consume more calories to keep up with the extra energy you have been burning each week. We would recommend lots of carbohydrates and healthy proteins to build up muscle to help in preventing injury particularly. Trackstaa enjoys a successful partnership with Xendurance who produce market leading nutrition supplements and we would whole-heartedly recommend any runner checking out their range of performance products, particularly if you’re looking to take your training to the next level.


1 Figure 1: Exemplar training paces for a 20-minute 5k runner. Humphrey. L. 2021. Luke Humphrey running pace calculator. [Online] [Accessed 23 April 2021] https://lukehumphreyrunning.com/hmmcalculator/race_equivalency_calculator.php