I’m marathon training! Why do I need to do speed-work?

Michelle Maxwell Coaching, Marathon, Psychology, Racing, Recovery, Running, Speed-work, Ultra Marathon

So the question I’m asked so often, especially this time of the year. Do I need to do speedwork, I’m training for a marathon? The simple answer is, no, of course you don’t need to, if you’ve run some 20 milers, you will get round. However, if you want to hit that start line in top form, most importantly knowing your marathon pace and heart rate (HR), knowing what half marathon and 10k pace also feel like, so you don’t start too quickly, then yes you really should do speed-work.

In fact, we are approaching the last 8 weeks of marathon training for some folk and this is the crunch time. It’s when all those miles you’ve been pounding out at slow pace start to have an effect, and running does actually feel pretty fluid and strong at marathon pace + 60-90s, or HR zone 2, for me (now in my 40s) this is 125-145. Now obviously you need to be able to run for 26.2 miles at 60-90s quicker than you have been running those long runs, and if you’ve been running them quicker than this, then you need to re-evaluate your marathon time!!

Michelle Maxwell running in the London MarathonWhen I did my last road marathon, I knew I couldn’t run 20 miles @ <7 min/miling in training, without it taking me 2-3 weeks to recover. However, this was my target pace. How did I know this? Through speed-work sessions, testing out marathon pace on tired legs in long runs, racing a half marathon and coaching experience.

So how do you use speed-work to get you to the start-line in top form?

There are 3 types of speed-work for longer events, half marathons, marathons and ultras (yes, even ultra-runners should do speed-work!).

1. Hill-running / Fartlek running:

Michelle Maxwell running up a sand duneThese sessions are useful early in marathon training, so in the first 6 weeks of a 16-week programme, what they used to call the base-phase. These session help get your body ready for the speed-work later on, they provide strength work, in addition to specific strength training sessions, for your legs through driving your legs up the hills, and gentle speed-work which more than anything just breaks up the monotony of pounding out slow miles.

2. Paced sessions / Tempo runs:
Running at specific paces or heart rates enables your brain to recognise the pace you want to run at on race day. Tempo runs quicker than marathon pace for example, provide you with the confidence that you can actually hit the slower marathon pace on the day. They make that pace feel easier. Training at 10k to half marathon pace for 3-6 miles also pushes your heart rate into that uncomfortable zone 3-4 zone, what they call the ‘sweet spot’. Pushing this boundary can enable you to train for longer periods in this zone without hitting the carbohydrate burning wall. Before and after such sessions, do ensure your carbohydrate stores are topped up.

Then there are the specific marathon pace sessions. These sessions simply teach you what is your realistic marathon pace, the pace you can achieve over 26.2 miles, but also the pace that does push you slightly out of the comfort zone. If training for a 50k or even 60k ultra, I will still run sessions like these, as they still help your body to push on when tired. For longer ultras the principles are the same, it’s just that the pace you push at is slower than marathon pace! So back to road marathons: The paced run. When should you do it? For how long? What part of the run?

For the first 6 weeks of marathon training, I suggest to my athletes to just run easy on all long runs, unless you are a seasoned marathon/ultra-runner these long runs take a while to get used to. This slower paced running teaches your body how to run efficiently, how to burn fuels effectively and how to recover. This adaptation usually takes around 4-6 weeks. I suggest to always start easy 90s-120s+ marathon pace and gradually increase the pace to a possible 60s above the pace we feel we are aiming for at that time. Then towards the end of the run, with 3 miles to go, gradually increase towards the current target marathon pace (I say current here, as I do find quite often that the slightly pessimistic pace of an athlete improves with time!), but don’t actually push hard at all, just finish feeling strong and quicker than you started. With 12 weeks to go, add in some faster sections to your long runs. Again start the long run at your 60-90s+ marathon pace and finish with 3-5 miles at your target marathon pace. With 8 weeks to go increase these sections and add in multiples, such as 3×3 miles @ marathon pace, or 2 x 5 miles, or 8-10 miles. I suggest these sections to be in the second and third sections of a long run, with the first third as easy pace.

The timing of these runs and how they fit into your week are very personal and hard to prescribe in general terms to everyone, but their benefit to your marathon and your confidence of achieving that pace for the distance are undisputable. Some runners need to focus on their endurance, their ability to knock out a sub 40 10k regardless of training is always there, but can they transfer that to the marathon distance, often they can’t. Then you have the athlete, I class myself in this bucket, that can churn out a marathon at a pace only just above double their half marathon pace. We are all different! Hence why off the shelf schedules for marathons, and indeed most distances, don’t always provide exactly what an athlete needs to hit that start line in top shape.

3. Speed endurance / VO2 max sessions

Why would a marathon runner need to run these sessions? Why is my coach telling to go to the speed sessions, surely I just need to run at my marathon pace, not at 5k pace!

Well, this is true to a degree, but it’s impossible to maintain all your runs at marathon pace without breaking down after a few days/weeks, that is of course if your marathon target time is actually one that is pushing your comfort zone! To reach that marathon start line in top shape, speed-work that pushes your VO2 max, or in simple turns, the maximum amount of oxygen your body can use during exercise, is pretty key. Unsurprisingly, elite marathon runners have a high VO2 max. So how do you train your VO2 max to improve your oxygen uptake, as obviously increasing your ability to use oxygen improves your muscle contraction and makes you a faster, more efficient runner.

In the first few months of marathon training I tend to suggest sessions involving lots of hills and fartleks, and some tempo runs but only at the target marathon pace at that time. Other longer speed endurance sessions involving 2 miles, mile or half mile or timed based sessions, like 8,6,4,2 mins are great though, more than anything to break up the cycle of slower running, but also to provide some confidence to the athlete that there is some speed in there still.

Heart rate - speed sessionMoving into the last 8 weeks of the training cycle, I recommend ditching the hills and focussing a bit more on 10k and 5k pace sessions, just one session per week, on the track or wherever you have available. By this point the athlete is happy running 18-20 miles with improved efficiency, has practised fuelling and is familiar with marathon pace. It is these faster paced speed sessions, mixed with the marathon pace efforts that can increase that oxygen uptake efficiency just a little bit. What would a session like this look like on paper? Here is my HR report (left) from the speed session (2×1200, 4 xhills, 6×600) with the Chippenham Harriers this week.

Above all when moving into this area of the training block, it is crucial that recovery runs are just that, recovery. Don’t be tempted to run them at marathon pace or in that area between marathon pace and easy. It just wastes energy and leaves the athlete drained, save the effort, for the effort sessions. Finally, the lovely thing about incorporating speed into your weekly runs is that it makes marathon pace feel so easy on race day, to start with anyway :)