Aerobic glycolysis depends on...?

You may find what you want here:

http://en.wikipedia.org/wiki/Cellular_respiration

or here:

http://en.wikipedia.org/wiki/Glycolysis

Check out McArdle's Syndrome.

If I remember correctly an individual with McArdle's cannot effectively convert muscle glycogen (they're missing the enzyme myophosphorylase) into glucose, therefore can only utilize blood glucose or fat oxidation for aerobic exercise.

This syndrome can be quasi tested for in a lab. These people see no rise in blood lactate in response to exercise (ischemic or not) along with extreme fatigue. Indicating a likely glycolytic block. However, after a few minutes of exercise they can sustain exertion indicating a shift into fat oxidation and aerobic glycolysis.

Besides that, glycogen staining (periodic acid shiff) can be used on muscle biopsies from muscle that has been fatigued either volitionally or through stimulation. You should find that glycogen levels will be intact in the fatigued muscles. There may also be a blood test for myophosphorylase deficiency, but I'm not sure.

Not really, for example:

- wiki doesn't mention role of creatine

- doesn't mention role of thyroid

- doesnt' mention role of capillary system

and so on, and so on...

wiki always was poor source of information, especially when you are looking for something from runners point of view.

If you have url for such article about athletic performance, it would be great.

anon wrote:

Check out McArdle's Syndrome.

thanks alot, checked - it's clearly not my case.

If this is a normally healthy runners who is just slow then it's not going to be McCardle's syndrome. People who suffer from that condition can't do normal exercise due to the absence of the muscular form of Lactate dehyrdogenase which converts glycogen and glucose into lactate.

You haven't described the runner's training and race times etc.

We need more information to help you.

welInow wrote:

We need more information to help you.

It's all about me

Running 2 years now, 35 yo.

In just a few months I was able to get decent speed (considering my age and my lifestyle), 1'10''/400m, maybe even 1'05'' (never tried all-out race) without any anaerobic training at all.

Then it stopped. I'm unable to maintain any decend speed at distance above 1-1,5k. My friends with same speed (around 1'10'' 400m) are able to run 4'30'' with 80% HrMax, while I have problems with 6'00 at such heart rate. Even with 400m run I'm dying after 200m, no matter if I'm starting slowly or fast.

Training - maybe 40-50 mpw, with long runs, strides, hill running, lots of aerobic work. 2 years without aerobic improvement, so I gave up and now trying to find out what is wrong with it.

My first though was about thyroid, but maybe there are other conditions.

There is nothing wrong with you, keep training.

welInow wrote:

There is nothing wrong with you, keep training.

Then why everyone I know have no problems with running long miles with average speed 2 min / mile better than I can, while I'm faster than them?

I know %HrMax can be tricky, i.e. beginner can run whole hour with 90% intensity, but it's not my case.

Ah, I forgot to add

use high doses of creatine as supplement added like 30'/km to my training speed. Still nowhere near normal aerobic speed of 1'10''/400 guy after 2 years of training.

Sorry, the wiki links already contain more information than I know or want to know. If I gave you more links, they would just come from wiki (e.g.

http://en.wikipedia.org/wiki/Creatine_kinase

) or Google. You can do this yourself, and probably already have.

By 6:00, I guess you mean 6:00/km, while your friends run 4:30/km? That does seem unusually slow at 80% MaxHR, if you've been running 40-50 miles per week for 2 years now. I gather you're doing similar training as your friends?

You mentioned long runs, strides, and hills. How much work are you doing at "tempo" pace, and how much interval training are you doing? "Tempo" training should make 80% HR running faster, and 400m reps at 10K pace with partial (e.g. 45 seconds) recovery should strengthen your heart and bring your heart rate down.

I don't know if it's aerobic glycolysis, but I don't see iron on your list. Did you rule out anemia?

Or maybe you are just a sprinter, and doing the wrong training.

Yes, I'm doing pretty similar training - alot of aerobic, stamina, tempo runs and so on. 6'00'' @ 80%HrMax is slow for 2 year of running, but for a guy who can run 3'20''/km it's disaster. My predicted 10k time is below 40', and I'm lucky getting 47-48.

It's not problem with my heart, my resting heart rate is around 45 now, sometimes go down to 40. I have also pretty slow breathing rate, like 4/4 (4 steps in, 4 steps out) at 80%, while others usually have much faster, even 3/2.

I'm blood donour, so no chance for anemia here too. My blood results are always in upper limit range.

It's seems either my muscles can't get enough oxygen / food, or cannot burn it effectively. As long as I'm on anaerobic fuel source, I'm doing great. But once I'm trying to run faster on longer distances, my heart rate go up, I'm feeling unusually tired yet still my breathing is easy.

There's nothing unusual you're not telling us?

Are you heavy/overweight?

Are you unusually short, tall, or otherwise disproportionate?

Do you have a "different" diet, e.g. vegan, vegetarian, caveman, Atkins, where maybe you are low in something?

Do you donate too much blood? Maybe your blood volume is always low (ask them to save it, and put some back next time!).

How are you predicting your 10K time, from the 400m?

For a 48:00 10K:

- Daniels predicts a 1:31 400m

- McMillan estimates a 1:22 400m

- Purdy equates it to a 1:09.61 400m

Comparing sprints to distances, Purdy is the most reliable, and Daniels is the least. If you only do a 70 second 400m, Purdy equates that to a 10K at 48:00. Even for a 65 second 400m, Purdy predicts a 44:00 10K.

Maybe you are just unlucky, for distance running, because of something normal like being mainly fast-twitch, having a heavy bone structure, or bad mechanics.

priority #1 - see a doctor. we have no idea of your medical history and even if we did, most of us aren't doctors. i would have suspected iron as well.

aerobic/anaerobic glycosis is kind of a misnomer. glycolysis does not rely on oxygen. glycolysis converts glucose to pyruvate. this happens in the cytosol, NOT in mitochondria. pyruvate goes into the mitochondria i believe via a monocarboxylate transporter. then pyruvate gets converted to acetyl-coenzyme A by an enzyme complex called pyruvate dehydrogenase. acetyl-coenzyme A goes into the Krebs cycle, which produces a bunch of NADH and FADH2, which move along the electron transport chain, eventually donating their electrons to oxygen, forming water and ATP with some hydrogen ions that get shuttled across the mitochondrial inner membrane through an enzyme called ATP synthase. so we see oxygen is not involved in glycolysis.

thus all the capillary, hemoglobin, red blood cell stuff shouldn't really matter.

so i think tomtom is asking the wrong question, and i don't think him or any of us will be able to figure this one out with this limited information.

an alternative is maybe tomtom is just kind of a wuss.

HR is way too variable between people to be useful. you can find 30 year olds that have max HR's of 170 and max HR's of 210. you can find highly trained individuals with resting HR's of 35 and 75.

tomtom you might consider throwing down the $150 or however much for a vo2 max test.

your ability to sprint doesn't necessarily have much to do with your long endurance. i have a 2:28 marathon but my quarter PR is 61.85. i was the slowest quarter runner on my college distance team and was even slower than some of the girls.

go see a doctor.

I never heard about Purdy, seems I have something to read about tonight, thanks :D Calculating from my 400m/1k times, seems it's accurate now.

There's nothing unusual about me, besides two facts - I had borderline hypothyroid and vitamin D deficiency due to my computer work (didn't saw sun few years in row, hehe). I'm vegan too, but I ran all tests on vegan deficiences (iron, B12, protein), seems I'm way above average. And vegans have no problems to become champions, vide Kenyans (90% vegan diet).

Well, seems Purdy hitted the nail - using my predicted 5k result from 400m time @ Purdy and typing it in McMillan, I'm getting correct values of my training paces now. Still McMillan predict now my 1k time as low as 3'50'', while in reality I'm running it 30 seconds faster, but if you say McMillan is wrong, let it be.

Still I can't understand why everyone I checked who run 400m-1k as fast as me are MUCH faster at 80% HrMax (or at average easy run), and why using simple carnitine affected my running speed.

other stuff:

no clue what you meant about 'everything goes through the liver' particularly if we were discussing skeletal muscle

creatine has nothing to do with glycolysis and krebs cycle, other than the fact that ATP generated during these processes can be used to turn creatine back into creatine phosphate. creatine phosphate is the most immediate source of energy for muscular contraction as it floats around the cytosol right next to the contractile apparatus of your muscle.

you also mixed terms creatine and carnitine. creatine i just described. carnitine, specifically a transport protein called carnitine acyl transferase (CAT), shuttles fatty acids into the mitochondria for beta-oxidation. if it's actually carnitine you're taking and it's improving your performance, maybe you have messed up CAT.

i am totally clueless about possible genetic CAT abnormalities. once again, go to the damn doctor.

@Surly - thanks, but I bet it would be very, very hard to get a doctor who can find out why healthy guy can't run aerobically as fast as he want. Especially in Poland.

Anyway, I will study this Purdy thing.

surly wrote:

you also mixed terms creatine and carnitine.

yepp, I never intended to mention creatine :P

also the conversions are stupid. usually they will assume an equal training status across events, which usually doesn't make a whole lot of sense unless your name is Rod Dixon. most of us have some genetic inclination toward a specific type of event. i can't say i agree with any one set of conversions. but for Purdy to say a 65 sec 400 equals a 44 min 10k? would my 61.8 400 equal a 39 minute 10k or so? cause i can run 32 high. i have found mcmillan's conversions to be the best.

It is your thyroid, and eat some meat. If you are Vegan and eating too much soy this will exagerate your hypothyroid state. If you want to run fast eat some meat and get a full thyroid panel at you next check-up. Also, if you have been running HypoT for a while your adrenals could be fatigued; this will slow you down real fast.