There is a slight chance people don’t know what a base is. So I’ma gonna go ahead and define it. It’s is just your weekly milage you’re running all the time before you have a green light to start a program, ideally. It’s not just a random number that coaches and writers of training plans, like me make up for no reason. Right now I’m in a base building phase for a potential 1/2 marathon the long weekend in May at Bluenose for the 15th anniversary, so excited!!! It might also be the most often ignored thing in those training plans. So why is it so important? How do we come up with it? And what do you do if even after reading this you’re still going to ignore it too?
Why is a base important?
In a sentence because it keeps you healthy. This is two fold, one is to avoid injury and the other is to make sure your training plan isn’t going to make you too exhausted, sick or worse. Say you decide to tackle a 1/2 marathon training plan, lots of running in the near future, about 500+ km in about the next 12-ish weeks. If you run about 5km every 10 days or so now and leap into that you will be EXHAUSTED starting in week one and stay that way for the duration of the plan. In fact I would think it’s pretty likely you’ll give up by week 5 or 6 because of it and that’s not what we want for you when we wrote it!

Worse than that you’re way more likely to end up injured and that might mean you never run again, and we really don’t want that! Keep in mind though if you do get an over-use injury almost 100% of the time some rest and physio exercises and you’ll be right as rain again in no time. While being cold or tiered doesn’t make you sick being tiered and pushing yourself too hard can lower you immune system and make it easier for you to pick up a passing cold and it can take you longer to heal from it if you do. That’s why having a good base to start from is just so darned important. That’s why all the good plans specify a base to start from.
How to we determine the right base for a plan
It’s a judgement call but it really should be around 90% of what your are doing in the first week of training. That’s to avoid breaking the 10% rule right off the bat. But it’s not something you totally have to adhere to, though it probably is best practice. When a training plan writer picks a base it is something they want you to have been maintaining for a while so there might be more than a 10% jump in the first week. Because of this they might also want you to not be intimidated to start by picking a base that is too high. This is basically how I pick the bases for my plans somewhere shy of the 10% rule but I think of it as something you’ve been maintaining for a while. Since I know a lot of people might not always listen I always include at least two bonus base builder weeks. These weeks take you to the first week of training without breaking the 10% rule. They also usually have either fewer workouts each week, shorter workouts or both. That way if you’re not quite at the recommended base milage you can build to it within the plan while establishing the same routines you’ll be doing later. We want you to go for your goals but we also don’t want you to end up injured so it’s a delicate balance between these two factors.
What to look for in a plan about bases

Something I always yammer on about how is if a plan that doesn’t mention injury prevention (especially a running plan) it is probably a bad plan. That’s totally true by the way! But a plan that doesn’t suggest a base to start from is probably a bad plan too. Including base builder weeks isn’t standard practice at all and I don’t think explaining a base is either. Really there isn’t much reason to explain the rational for a base. It just is what it is. It is what the writer thinks you should be doing regularly before starting the plan, but it really should be there.
Tips and tricks for base building
- It’s not the best idea to JUST get to a weekly milage specified as the required base and then immediately start your plan. We want you to be running that for a few weeks at least, before you start.
- If might seem tempting to maintain a base milage year round for your favourite race distance, but that might also be too much running for you year round.
- Build your base to the first week of training and keep that for 2 or three weeks before starting you plan as a best practice.
- Base time is a great time to break in new shoes or gear to cycle into your upcoming training program.
- If your plan of your life specifies the days of the week for your workouts try to match this in base training so in week one you’re already in the groove.
- Remember to celebrate running on your own schedule, picking the distance each day for yourself and the intensity you want to workout on a given day. That won’t be an option soon.
- If you don’t have a base recommendation in your plan (consider the quality of the plan as a whole) and take 10% off week one as your goal to get to for your base.
- Throw some speed work like fun fartleks in, to mix things up if you’re getting bored.
- If you have lots of time between races taper down your base to a lower level and a bit of a break for you body before ramping it back up again.
What if you’re still going to ignore this?
I suspect that often times plans specify a base and athletes just ignore it. That’s fine if they are running more than that already or very nearly there. But I also suspect people start from not a whole lot of miles a week and lack some consistency and just dive into their plan anyway. For the record you shouldn’t. But training is a big time commitment and I get the reasons people start from a base well below what a plan specifies. Officially put off your race and spend more time before you start building your base. If you’re not going to do that make sure you have some new or mostly new shoes for maximum support (you reckless fool, jk sorta). Next make it a point to foam roll for a while every day to minimize soreness and maybe minimize injury. Take extra special care of your self, cut as much junk from your diet and prioritize getting more sleep. Especially if you’ve had a previous injury start you physio exercises at the start of your plan to prevent injuries from the start. This measure is to try to counteract the not so great choice of not listening to base recommendations. If that doesn’t apply to you, think about adding stretches and yoga to your daily routine for the same reasons.