Breaking the Wall

August 17, 2019

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Location:

Orem,UT,United States

Member Since:

Jan 27, 1986

Gender:

Male

Goal Type:

Olympic Trials Qualifier

Running Accomplishments:

Best marathon: 2:23:57 (2007, St. George). Won the Top of Utah Marathon twice (2003,2004). Won the USATF LDR circuit in Utah in 2006.

Draper Days 5 K 15:37 (2004)

Did not know this until June 2012, but it turned out that I've been running with spina bifida occulta in L-4 vertebra my entire life, which explains the odd looking form, struggles with the top end speed, and the poor running economy (cannot break 16:00 in 5 K without pushing the VO2 max past 75).  

 

Short-Term Running Goals:

Qualify for the US Olympic Trials. With the standard of 2:19 on courses with the elevation drop not exceeding 450 feet this is impossible unless I find an uncanny way to compensate for the L-4 defect with my muscles. But I believe in miracles.

Long-Term Running Goals:

2:08 in the marathon. Become a world-class marathoner. This is impossible unless I find a way to fill the hole in L-4 and make it act healthy either by growing the bone or by inserting something artificial that is as good as the bone without breaking anything important around it. Science does not know how to do that yet, so it will take a miracle. But I believe in miracles.

Personal:

I was born in 1973. Grew up in Moscow, Russia. Started running in 1984 and so far have never missed more than 3 consecutive days. Joined the LDS Church in 1992, and came to Provo, Utah in 1993 to attend BYU. Served an LDS mission from 1994-96 in Salt Lake City, Utah. Got married soon after I got back. My wife Sarah and I are parents of eleven children: Benjamin, Jenny, Julia, Joseph, Jacob, William, Stephen, Matthew,  Mary,  Bella.  and Leigha. We home school our children.

I am a software engineer/computer programmer/hacker whatever you want to call it, and I am currently working for RedX. Aside from the Fast Running Blog, I have another project to create a device that is a good friend for a fast runner. I called it Fast Running Friend.

Favorite Quote:

...if we are to have faith like Enoch and Elijah we must believe what they believed, know what they knew, and live as they lived.

Elder Bruce R. McConkie

 

Favorite Blogs:

Miles:This week: 0.00 Month: 77.26 Year: 2379.27
Saucony Type A Lifetime Miles: 627.15
Bare Feet Lifetime Miles: 446.12
Nike Double Stroller Lifetime Miles: 124.59
Navy Crocs Lifetime Miles: 2133.34
Navy Crocs 2 Lifetime Miles: 1263.81
Easy MilesMarathon Pace MilesThreshold MilesVO2 Max MilesTotal Distance
13.450.000.000.7514.20

A.M. Total of 12. 5 with Benjamin, 3 more alone, ran 0.75 in 4:01 feeling good, in fact, I was planning to run it in 4:12, but after seeing how easy the first quarter was, I decided to keep the pace. I was happy with it because it is has five 90 degree turns. 2 with Jenny. 1 with Joseph and Julia - Jacob ran 0.5 of that. 1 more alone.

I got curious about how much energy running burns and decided to research the subject. I started by looking up different calculators. Every single one of them uttered the absolutely ridiculous heresy. 5 miles at 6:00 pace takes the same or less energy as 5 miles at 12:00 pace. What a joke! The conclusion is obviously absurd. Take took guys of the same weight with 20 lb of fat they can lose, feed them the same diet, have one run 5 miles at 6:00 pace every day, have the other do the same at 12:00, do that for three months, then weigh them at the end. The 12:00 guy will lose 5 lb maybe, the 6:00 guy will have all of his extra weight gone!

So I decided to track down where this heresy comes from and found a paper that used a linear approximation of VO2 as a function of speed with positive values of a and b, so VO2 per minute per kg = a*V + b where V is velocity. Well, if we try to do it per unit of distance, since t = d/V, we get  VO2 * t = (a*V +b)*t =  (a*V+b)*(d/V) = d*(a + b/V). From this formula as V increases, the energy required to run a unit of distance (e.g one mile) decreases! That is what those calculators base it on. Now that I am remembering, this is actually an accepted fact that VO2 increase with speed is linear.

This may very well be true, but I think what the formula is missing is something like c*V^2 term, or possibly a higher power to account for the anaerobic energy use. It is wrong to assume that all "aerobic" exercise is 100% aerobic. And from what I remember about the Kerb cycle reactions, the anaerobic energy is very expensive - you have to burn a lot of carbs for that extra 10 seconds per mile of pace.

There may be another explanation as to where the energy goes, but the point is - running faster requires more energy per unit of distance, not just per unit of time.  If you have just written out a fancy proof with the end result being that 1 = 3 you may not know where your mistake is, but you can be 100% it does exist.

P.M. 2.2 miles.

Green Crocs 2 Miles: 12.00
Night Sleep Time: 0.00Nap Time: 0.00Total Sleep Time: 0.00
Comments
From jeffmc on Wed, Oct 12, 2011 at 02:29:53 from 68.227.2.226

putting aside the calculators, there is an element of truth to what you found as there have been studies performed that found that in addition to the linear increase of VO2 to increase in velocity, there is also a relationship between ml/kg/km of O2 used during running. These studies found that at constant speeds the amount of O2 used per km of running was constant whether or not the individual was running fast or slow.

The elite Africans seem to be getting numbers in the 190-200ml range on average, with Zerseny Tadesse being recorded at about 150ml of O2 per kg/km which is the lowest ever recorded level of O2 used.

What I think that the studies are leaving out is that they are trying to use O2 consumption to calculate metabolic cost, when it is apparent that VO2 is not the only factor in play. So, while VO2 use per km may remain constant at different velocities it does not mean that metabolic cost reacts in an equivalent fashion.

Using Tadesse as an example supports this, as with his VO2 max in the 80's, and a ml/kg/km of O2 consumption in the 150's, he should be able to run a marathon in under 2 hours if he is able to run the full marathon at a level equivalent to what his O2 numbers tell us. We know that this is very far from the case as he has never to my knowledge broken 2:12:00 in the marathon and has dropped out on a number of occasions.

So, I think that the calculators are simply trying to give the best estimate that they can with the knowledge that we currently have. The problem is that we don't know exactly what determines the metabolic cost of running or how much it "costs" to run a mile in 6:00 vs. 10:00. All we know is that the amount of oxygen used to run the distance is approximately the same even when practically disregarding the velocity we are running at.

From Sasha Pachev on Wed, Oct 12, 2011 at 16:35:40 from 192.168.1.1

Jeff:

Do you know if anybody has tried to measure the mechanical energy required to run? This should be fairly simple if you have a treadmill with force plates. You can get the work against ground from the ground reaction forces, and assume that the work in the air is a small constant fraction of that.

From jeffmc on Wed, Oct 12, 2011 at 17:40:05 from 131.216.80.154

Rodger Kram up at the University of Colorado has done a lot of work with energy cost of running, and has an Alter-G treadmill that he built force plates into. The focus of his research is looking into the energy cost of locomotion (walking, running, etc.). He has even done research with animals (from elephants to bugs) to compare their energy cost to that of humans. I would look him up first and then branch out from there.

I believe that some other researchers figured out a way to determine caloric cost of running as well, although I do not recall their methods. That would be something to look at as well.

From AZDesertmonsoon on Wed, Oct 12, 2011 at 19:02:14 from 204.17.31.126

Here is a word doc of a study called "The Effects of Running Speed on the Metabolic and mechanical Energy Costs of Running" in the Journal of Physiology Online.

This study suggests that the metabolic cost per distance remains relatively constant across running speeds while mechanical cost per distance decreases as speed increases.

http://www.google.com/url?sa=t&source=web&cd=1&ved=0CBoQFjAA&url=http%3A%2F%2Ffaculty.css.edu%2Ftboone2%2Fasep%2FHarris.doc&rct=j&q=THE%20EFFECTS%20OF%20RUNNING%20SPEED%20ON%20THE%20METABOLIC%20AND%20MECHANICAL%20ENERGY%20COSTS%20OF%20RUNNING&ei=QRGWTvbrKJTjsQKD15jwAQ&usg=AFQjCNF1BpcxNPnyMp-Fgd_mZUcSom4d9g&cad=rja

From jeffmc on Wed, Oct 12, 2011 at 21:41:27 from 131.216.80.154

Interesting article. I would be interested to see if someone has performed a similar study at faster speeds. The runners in this study had 10k times ranging from 29:30-36:00 yet their running speed ranged from about 11:30-6:40 per mile. The runners told researchers that the two fastest speeds (3.67m/s and 4.00m/s) felt the most comfortable, but those are also the speeds that were the closest to the speeds that most of the runners trained at. Would mechanical cost for these runners climb as they started to run at speeds that were not so easy?

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