Where does speed come from?
Digging into my data
On Saturday I ran 30:27 over the 10k, finished second in a sprint finish. Friends were not sure whether or congratulate or console me. I guess that’s because making statements like, “I am going to try to go sub-30,” can be confusing.
But as I told Gautier today, the time is correct. I mean, can I expect to go faster without doing the work? More intriguing is to wonder how I ran that time given the training context, and still, where the hell does speed come from? Is it won by explicit practice or can it arise as a kind of externality?
From the gun, I pushed my way through the pack of scrawny road runners to assert my lead. I clipped the first 3k at 3:00 average, but soon we were charging uphill and falling off pace. Behind I heard the clop and chuff of the herd, felt their neon anguish at my heels. I resisted the urge to slow and tried stay present with my mechanics.
Through 5k and we make a U-turn, some guy attacks and I sit-in behind. He surges and relaxes, I match and flow. Over the last ‘big’ hill I see him struggling, wheezing breath and strides landing short. I work the hill with galloping ease. Though I am suffering, I think I will survive.
On the descent he is attacking again and we roll through the curves side by side. In the end I was too patient, we hit the track together, me with a slight lead, but over the last 100 meters the guy flies! I’m eating dust as he crosses the line and collapses. I stand there and catch my breath waiting as the medical team attends him.
When you get beat like that you better give it up. As he made it to his feet I was right there to shake hands. He proved capable of giving it all and I was not that tired. I put out what I had, but context is everything.
I signed up for the race on a whim, because Gautier was going and because I wanted to see what I could run in the midst of heavy endurance training. And that type of training makes it hard if not impossible to turn yourself inside-out over 30 minutes.
January Training
Given that ski-mountaineering predominated in January, we have to assume it plays some roll in speed development—or at least support. But how is that possible? Going uphill is almost entirely done at a walking pace meaning cadence is low, foot-speed sluggish.
Is it time at altitude? Is it the strength-effect of uphill meters with the added weight? Or is it simply running freshness and the repetition of short runs with fast strides?
My hypothesis was that by polarizing the training between aerobic skimo and run sessions in the easy or speed domain (but never between) I could get faster. The interaction between training stimuli should produce a robust aerobic system with access to a bit of speed.
What I was missing of course was speed endurance, not enough volume at race-pace, making it feel too much. But I think with the addition of some longer interval lengths improvement is rapidly attainable.
Road Running the sport
Only marginal progression visible here, but the 10k in 23’ was a fast course and yesterday’s route was pretty challenging. Strava indicates that I ran at a grade-adjusted-pace of 3:01 min/km yesterday.
The missing link is the marathon. Given the comparatively small depreciation of pace from 5 to 21km, the data suggests I could run a fast time, but that remains imaginary.
The pace curve here is very flat between 2’ and 1h. To my eyes this indicates that the aerobic work—the staple of my training philosophy—gives firm support to this pace range, but without access to top-end speed presents clear limitations.
Road running is a beautiful sport, ok not as cool as trail running, but the road does not lie. Improvement makes you hungry for more. But tempering this appetite is important.
In my case I need to ask if its worth it to shave a couple seconds off my times. If going sub-30 is pure ego or a viable path to a faster 100k mountain race. I think we know the answer.
I think it’s purely your aerobic fitness that allows you (or us elite trail runners in general) to run relatively fast on the flat. Like faster than you would expect given the fact that you (we) hardly do any speed work. And the thing is, you can train your aerobic engine regardless of the endurance activity that you choose: whether you’re running, skiing or cycling for your metabolism it’s pretty much the same thing. My best hypothesis is that your limit is not the rate at which your engine can produce the energy (so vo2 and lactate threshold mainly) but it’s a mechanical limit that reflects in your running economy. Take away those 60h of skimo training and your running performance on the 10k would likely be a lot worse. Great work and thanks for sharing!