TRAINING: Speed, Fun and Efficiency in Aerobic Session

After Sunday’s cross-country, I couldn’t know exactly how the body would respond but Monday’s easy 35-minute hill run had given me the impression that recovery would be swift, so I decided not to change my 60-minute marathon pace session before testing how the legs felt.

The aim was to run around 15k in 60 minutes and then a further 6-7k as warmup and cooldown to do a session around the half-marathon distance on the track.

As many runners, my head felt a bit weary from recent training, though, and with all the miles having to be done on the track, I had to come up with a way of making the session a bit interesting. So to achieve this I decided I would first run a 5000m aiming to go sub-21 minutes (my marathon-pace workouts currently have a target pace of 4:10min/km). I would then jog for a kilometre before doing a 10000m in sub-42 minutes.

One of my ambitions is to one day run a 10k race on the track, so this workout could double up as giving me a feeling of how the distance feels on the track compared to the road. This may not constitute everyone’s idea of fun, but the approach worked pretty satisfactorily for me.

Aerobic Developments vs. Anaerobic Developments

Today I saw the first comprehensive signs of how aerobic training “pushes up your pace from below” as I set off at 4:05min/km pace and this had never felt easier despite the race on Sunday. This is what happens:

· A runner of my profile has a recovery speed around 10-11kph, a base pace between 12-13kph, a marathon pace around 14-15kph and a half-marathon pace moving towards 16kph. My maximal sustainable pace over at least a mile lies somewhere around 19kph.

In simplistic terms it means I have a range of speeds available between 10-19kph. As I run faster, I can maintain each speed for a progressively slower amount of time (10kph for possibly 24 hours or more, 19kph for perhaps less than 6 minutes).

I can do two things with these speeds:

1. Increase the time I can run each one at

2. Increase the min. and max. speed in my range of paces (e.g. to 11-20kph or 12-21kph)

There’s three ways to train “a pace range”:

1. Run slower than the pace for longer periods

2. Run at the pace for a set period (generally underdistance compared to race distance)

3. Run faster than the pace for shorter periods (often very short)

And the two main pointers you should use to decide on what to do:

· When training at paces that are anaerobic for you (for instance 16-19kph for me), you incur several negative effects as described by Lydiard. However anaerobic training works fast

· There are no negative side-effects of aerobic training. Aerobic training works slowly

What makes this choice difficult to make is that aerobic training “works from below” (imagine it like water rising in a bathtub). This means, you will see improvements first at 12kph, then 13kph, then 14kph and so on, until almost you’re entire range of paces has turned largely aerobic. This way it would take a significant amount of time and work until 16,17, 18 and 19kph become aerobic enough to be truly useful in a wide range of races.

Anaerobic on the other hand will improve your ability to utilise the speed you are targeting within a few weeks (running short sprints at 20kph will make 19kph pace seem easier, so will longer reps of 19kph, or even longer at 18kph and so on). This effect is short-term, largely detrimental, and will not cause these speeds to become aerobic enough for truly long term usage (you may increase your tolerance to these paces by a 5-10 minutes at the very best).

First Proof?

Today’s session versus my performance at the Dublin Seniors seem to illustrate this at work (because I only do aerobic training). The cross-country was quite anaerobic and due to the terrain I could only manage 4:05min/km for 40 minutes.

In today’s session I first ran 5000m in 4:13min/km (feeling very easy) then 10000m in 4:07min/km (still very easy). On the surface it looks bizarre that I should dangle helpless at 4:05min/km pace on rough ground, yet can churn out 1.5 times the distance with tired legs never being out of breath. I put additional running in before and after to add up to 22.5k (all on the track, my longest track session so far).

This development is not bizarre, however: This is exactly what will happen when you turn to heavily aerobic training. Your highest speeds will become largely unusable, for a time, while your system eats up your anaerobic speeds from below and turns them aerobic. (remember with training the principle "use it or lose it applies". Speeds you don't run at won't be effective, for a time, which is why timing of your training pacing in relation to target races is another essential part of our pyramid).

Lydiard's Boys Show the Way!

Hopefully, the next few months should start to see me doing 5000m and 10000m trials like these in 3:50-4:00min/km pace while remaining equally at ease. Only when racing season nears will true anaerobic training move in to make the remaining “high speeds “ more usable for races (note though, that unless you are a middle-distance runner, the only useful race paces are the ones you can generate using 97% or more aerobic energy). This combined with very specific work on running form, sprint drills and very fast leg work will then push up your new maximal speed further and next year you can start moving up your aerobic speeds further by another bout of aerobic work.

Shockingly, Lydiard's boys Snell, Magee and Halberg recorded improvements between 14% and 28% in the base pace they ran their 22-mile trail run in every Sunday from week 1 to week 12-20 of their foundation training (they started out at 7 minute miles and finished between 5 and 6 minute miles).

They may have been extraordinarily adaptable and may already have mastered a wide range of paces to improve this quickly. For comparison this would be equal to me being able to increase my marathon pace from 4:10min/km to 3:35min/km per hour within one base phase! A further caveat here is that Lydiard's boys were physically capable of running the majority of their aerobic running at the high-end of the aerobic spectrum.

I cannot currently do that but have all reason to believe that my improvement would hugely accelerate if I could. Sessions like yesterday's of 15k at around 6:40min/mile pace are the true catalysts for long-term improvement.


Some downsides to report, though, I had a pretty localised pain on the ball of my left foot just under the second toe from the right. This ceased when jogging slowly after and seems to be an irritation caused by running on the front of the foot more during the cross-country and then the fast session.

I will need to watch this closely and will most likely not do any more faster work this week but stay at recovery and base paces. First up: The first night hill run with head torch on Trooperstown in a few minutes.