What is the 10% Rule?
And why you should be using it
There’s so much conflicting advice out there on how much running is too much or how little is too little (so that you don’t improve). But in my experience as a running coach, there really aren’t any hard and fast rules. Apart from of course, the “10% Rule”. The 10% Rule is a guideline, suggesting that you shouldn’t increase your weekly mileage by any more than 10% from one week to the next. The reasoning behind this “rule” is that it aims to help prevent injuries associated with massive jumps in mileage. And we’ve all been there, especially when we first start running and realise that we are in fact runners, and that we love the endorphins! the buzz! the kudos! the kit! and we just want more and more and more…
But have you heard of the Terrible Too’s? Too Much, Too Soon, Too Quickly. This too-rapid increase in running volume, i.e weekly mileage, has been shown to significantly increase your chances of picking up a running injury and whilst the research is fairly limited, this common sense advice seems to have been around for a long time.
I tend to use this approach when training complete beginners, as I’ve found that focusing on a steady increase in mileage appears to work, especially at the start of a running programme. Often it feels like I’m the fun police though, as it feels like I’m curbing new runners enthusiasm- I’m not, I’m just trying to prevent runners from being injured and help them build a sustainable, long lasting relationship with running and, often, exercise more broadly.
We know that as runners we’re not robots and the running journey isn’t linear, so taking a holistic approach as your running relationship evolves and develops is far more beneficial than sticking to the “traintrack” of rules. However, here are just a few reasons of why a progressive programme is more beneficial than an all or nothing approach.
1. Injury Prevention
Gradual progression helps reduce the risk of overuse injuries, such as stress fractures, tendinitis, or muscle strains. Sudden spikes in volume or intensity (hills/speed) can stress muscles, bones, and connective tissues beyond their adaptive capacity, a 10% increase allows for safer tissue adaptation.
2. Sustainable Progress
By limiting weekly increases to 10%, you can make consistent, long-term progress without burnout or overtraining. This approach ensures that the body has enough time to adapt to each increase in load, preventing plateaus and setbacks.
3. Enhanced Recovery
Your body requires adequate time to recover and repair between sessions, especially when training intensifies. The 10% rule helps you to balance stress and recovery, which can prevent an accumulation of fatigue leading to either a decline in your performance decline or continued colds/illness that you just can’t seem to shift.
4. The Rule is Flexible
The rule is flexible and can be adapted to your fitness levels of where you are right now and not where you were last year/5 years ago. Your baseline and recovery vary, but by adapting the 10% rule you can conservatively approach your training that can either be scaled up or reduced depending on your personal response to your training.