Running economy and ultramarathon performance

After my testing on Monday I was wondering whether Paul Murgatroyd was looking at the wrong factor as a key determinant of ultra running performance so I sent him this email:

I have had a good ultra season so far, coming in top 10% in one race and consistently top 20%-25% in all others. My running economy is poor which might explain why I am not in the top 5 say but I wonder physiologically might there be some other determining factor behind decent muscle performance? Something anaerobic? These might be daft questions from a physiological layman but I wonder do you need to have a good running economy (in the terms you measured) to be decent at running ultras?

Specifically I was wondering whether ultra performance might be related to resistance to muscle microtearing, which might be trainable. Paul replied stating:

The determinants of running economy are yet to be fully understood and a good deal of research in this area is still ongoing. Certainly there will be an underlying genetic component (but how much is determined by this is difficult to say, with any great certainty) but one thing that is well reported is that running economy and other associated variables, such as LT and LTP, are more trainable than VO2 max.

I would anticipate that, as your quality and quantity of training increases - more miles and more speed work at the recommended paces - you will see a greater change in running economy and LT/LTP values thanVO2 max. Running economy and other factors, such as vVO2 max, have been shown to be important determinants of endurance performance and if we took two marathon athletes with similar VO2 max values, the deciding factor would be running economy - the ability to sustain race pace with lower energy demands/O2 consumption and thus offsetting fatigue. In terms of ultra-running, this is even more likely to be a performance indicator, due to the longer distances involved and the need for athletes to be as economical as possible and delay the onset of fatigue for as long as they can. [one of the UK's best ultrarunner's] VO2 max is not exceptional, but running economy value and speeds at LT /LTP and vVO2 max were amongst some of the best we've had so far. Interesting stuff!

The LT and LTP he refers to are the lactate threshold (point where a person moves from easy to steady running) and the lactate turn point (point where a person moves from steady to tempo running). My LT occurred at 11km/hr (8:44 mins/mile) and my LTP occurred at 13km/hr (7:23 mins/mile). Not too hot really!

His recommendations for me to improve as I mentioned in a previous post are to do more speed interval and tempo work. Specifically he has recommended 1-2 sessions per week of:

• Tempo - Warm-up, then 25-30 mins@164-172bpm (and/or ~13-14km/hr on the flat), then warm-down
• Intervals - 1M easy, then 3 x 1M or 6 mins@172-177bpm (at ~14km/hr), with 800m or 3-4 min recoveries, then 1M easy (increase to 4-5 reps over 4 months)
• 1M warm-up, then 6 x 600m or 2mins@175-180bpm (at ~15km/hr), with 400m or 2-min recoveries, then 1M cool-down (increase to 8-10 reps over 4 months)
• Warm up, then 2 sets of 4, 5, and 6 mins@172-177bpm (at ~14km/hr), with half-length recoveries and 6 mins between sets, then cool down
• Pyramids - Warm-up, then 1min up/down, 2 mins up/down, 3 mins/up down @175-180bpm (at ~15km/hr)- repeat 2x, then warm down

I had weekly sub 7 min/mile tempo runs as part of my training before the WHWR but didn't restart them due to the need to recover and just get some miles in my legs in preparation for the DOTH. I restarted my weekly tempo runs last week and did another one on Tuesday at ~ 14km/hr (6:51 mins/mile) to implement his recommendations. 1 mile warm up, 5 miles at tempo then 1.5 odd miles cool down. It really monsoon style pissed it down and I got soaked, my legs felt pretty heavy and sluggish, and my trainers filled up with water. Great. :-)

I then did a medium pace (7:58 mins/mile) and distance road run last night. It felt fine. Looking forward to a hilly 19 miler at the weekend before I scoot off to Vienna for a conference next week.