When we don’t see the speed improvements we’re hoping for, we often hear the cliche “train slow, race slow.” The implication, of course, is that we didn’t train hard enough, that we should have done more lactate-burning tempo intervals and lung-busting speed sessions.
There may be situations in which more speedwork is appropriate, but it’s a dangerous idea, and it’s wrong.
Over the last seven months, as I’ve been getting ready for my first ironman, all of my training has been slow. All of it. Before that, during marathon training, I did one tempo run a week (intervals at medium speed, a bit slower than 10k-race pace). Even then, 95% of my training was slow.
All that slow training has led to significant speed gains.
Last August, I ran an olympic-distance triathlon in 2:35:00 to finish in the 42nd percentile of my age group (M30-34).
This April, I ran a much more competitive olympic-distance tri in 2:24:45 to finish in the 75th percentile of my age group.
Between the two events, I did maybe a dozen tempo runs. Everything else was slow, aerobic, heart rate zone 2 training.
Well, OK, but what about at shorter distances, where speed is king?
I don’t have a lot of comparison data points, but a few weeks ago, I ran a (not entirely flat) 5k in 19:38 to come in 3rd overall. That was the first time I’ve placed overall, ever. And I did it without doing any speedwork. Exactly zero of my training was at or above my 5k-race pace.
A couple months ago, I ran a 40:59 10k, which won my age group. Again, none of my training even approached my 10k-race pace.
A few weeks after my ironman, there’s a local sprint triathlon that I’m looking forward to. I did the same race last year, so it will make an excellent comparison. I have no doubt that I will have shaved minutes off my time by doing lots of long, slow training.
If I were focused on shorter distance events, I would include more tempo intervals and speedwork. I’m sure that would make my top-end speed gains greater. But it comes with significant risk.
High intensity training is glitzy. Everyone who keeps a public training log (mine is here) loves to post a flashy time on a training run or ride.
But susceptibility to injury goes up dramatically with high intensity work.
For years, I did all my training near lactate threshold, and for years, I was plagued by knee injuries.
In 2008, I trained haphazardly, all toward the top-end of my speed range, for the Bolder Boulder 10k (which, coincidentally, is running as I type this). I finished with a weak 50:49 because I had to stop and walk due to knee pain multiple times.
No matter what distance you’re training for, the heart of your training should be a solid base of aerobic, zone 2 work. It will make you faster, and it will keep you out there training, instead of on the sideline, icing an injury.