A Sub 3 Hour Marathon

Congratulations to my mates at Ängby Runners that did the Stockholm Marathon yesterday - chapeau.

Following last week’s post on running with power and the breakdown of my 2:59:31 marathon, I have had some questions on how I approached my marathon training which I’ll summarize below.

Firstly you don’t need a coach to tell you what you need to do. You need a calculator!

Running at 04:15 pace for 42.2km means that you need a watts/kg critical pace of over 4.5 w/kg. We can estimate that you will be able to hold 89-91% of that power for the distance. I’m not a body fascist but if you have some non-functional weight that you can lose then it’s certainly a good idea to do so.

If we equate Critical Power to a maximal 10km race, in terms of pace we are talking about 03:50/km or a flat 10k time around 38m20. I did the Sickla 10km race on the 19th of September in 38m50s but it is a hilly tight course and my average power was 319w at 69kg  so I knew I was in the ballpark, the marathon was on the 6th of November so it was then down to working out how to hold on to 90% of that pace/power for up to 3 hours during the next 7 weeks of preparation. 

Here’s an analogy that I’ll use before combustion engines become a thing of the past. VO2 max is the size of your engine, and running economy is how much petrol you’re using at a given speed. Thus, it is important to have a big engine to race a fast time, but also to spend as little petrol as possible at faster speeds. This will allow you to push a little faster, while using the same amount of fuel.

Simply put, running high volumes at slower speed makes your body more efficient during running (even at high speed). This is why it is such a central part of advanced marathon plans. It also helps you to be well-rested for your less frequent high-intensity workouts, which help you make your engine bigger and more powerful.

Now for me, high volume running was not going to be part of the plan. I just didn’t have the time. So if like me, you are making a sub 3 attempt on volumes under 80 km a week you are going to have to err on the side of a bigger engine rather than relying on fuel efficiency. You’ll see that some running calculators predict sub 3 marathon time off 10km times closer to 40 minutes. Unless you are a true Prius I wouldn’t risk it.

So with the end in mind you can tailor your training. I think it was Jack Daniels who answered the question “How much training should I do?” with “As little as you can to get your desired outcome”. I have a bit of a problem with recreational marathon plans, for me, it doesn’t really make sense to take the principles that work for elite and sub-elite marathoners doing 160 to 220 km a week and just scale it back. My approach was to first train my 10km critical power/pace to a point where sub 3 was plausible and then work out ways to hang onto 90% of it for 3 hours.

You can get far on this simple principle from Coach Bill Bowerman and Olympic Gold Medalist Frank Shorter that they argued applies to most distances; “[do] 2 to 3 weekly interval sessions, a weekly long run and fill the rest with as much [easy running] as you can handle”.

That’s basically what I did for those 7 weeks between the Sickla 10k and the Uppsala Marathon. One short interval session, one long interval session and a long run rarely longer than 90 minutes. Then on the other days I just did around 60 mins of easy running listening to pods.

These were a few hacks that I also used:

• Weighted Vest Dog Walking - Motion is lotion, fast trail walking with a weight vest in minimal shoes to condition the feet and lower legs.

• Bike Bricks - I had an Achilles injury early in the spring so I wanted to avoid over-distance runs. At the same time I wanted to train my body to be relatively fuel efficient for the target duration. To do this I did 2 x 45 minute runs sandwiched either side of a long endurance bike ride.

• Strength Work - Free weights; squats, dead-lifts and overhead press to strengthen the kinetic chain

• Progression Runs - Adding a minimum of 5 km of marathon pace running to the end of my long runs.

• Swim Cross-Training - I kept the swim training going through the period. Swimming is a great non-weight bearing aerobic stimulus. 

• Tell People You’re Going For It - I had voiced my commitment. Saying it made me believe it and I didn’t want to let myself or others down. My son Max drove me to the race. He’d given up his day to support me. Having external (not just internal) motivation helped.

As much as coaches, sports scientists and wearables manufacturers have a vested interest in making training appear complex, just start with the end in mind and work back from there. Keep it simple, do the work and enjoy the process.