Physiology of lactic work counteracting aerobic work

Oregon Old Timer wrote:

. There are a zillion factors that impact the fate of lactate. I worked for 3 years on this single question with Dr. Bruce Gladden at Auburn University and we only scratched the surface of it. 20 years later he is still asking the same question. If you want to understand lactate metabolism, search "Gladden, LB" on Pubmed. It will give you everything you probably want to know and then some.

Thank you for the reference. You made some good points in your post!

aduck wrote:

Glad someone brought up Canova...I remember reading an article describing his "Special period" which combines long anaerobic threshold workouts with short aerobic speed workouts in the same microcycle to be used as a buildup to prepare for goal pace or race specific workouts. Granted these speed workouts are relatively low in volume and with full recovery. So its understandably important in this case to at least pepper in these workouts, to stay in touch with speed.

Thank you. I may use this sort of thing as a transition between pre-competition and competition period workouts.

all that baloney about "destroying aerobic enzymes" merely obscures the fact that you will never get anywhere near your full aerobic workload unless you are also working anaerobically at a very intense level.

As I explained before, it is all about the rate of gas exchange between blood and muscle. A higher pH differential speeds gas exchange dramatically, meaning low muscular pH is beneficial. Oxygen unloads from hemoglobin, and CO2 and H+ is taken up by hemoglobin, much faster when muscle is more acidic. This is why it takes a while to "get going" aerobically and distance races tend to start out fast before settling in.

If you want to maximize your body's O2 consumption, you must consume the maximum O2 possible. That means stress yourself aerobically under concurrent anaerobic stress, e.g. interval work or 600 meter repeats. Then take the appropriate amount of recovery. If someone convinces you that your aerobic enzymes are gone, wait till they're back, then work out again.

If you are trying to preserve those enzymes by holding yourself below some anaerobic threshold, you are merely training yourself to adapt to a much lower level of oxygen consumption. That is a losing strategy. You will move up to marathon by age 25 that way.

I have posted links on previous, searchable threads if anyone is going to bother me about this SIMPLE and WELL KNOWN fact.

You pretty much nailed it. But the destroying the aerobic enzyme thing is pretty legit. But I think you need to define full aerobic workload. Ill take a shot at it.

If you want to increase your aerobic capabilities you must increase do a couple of things. You must increase aerobic enzymes which increases your bodies ability to aerobically burn glucose. You must increase blood volume. You must increase the capillary size and density in different muscle fibers. You must increase the mitochondrial density in different muscle fibers.

If you want to increase the amount of mitochondria in slow twitch muscles and increase aerobic enzymes then you must do long runs, tempos, and increase global mileage. If you want to increase the amount of capillaries in slow twitch fibers then you must do long runs, tempos, and cruise intervals/CV intervals.

This is all great in all for longer events but what about middle distance racing where you are still running primarily aerobically?

Well you use intermediate twitch fibers for this. They are still aerobic but are just faster and don't have the same amount of endurance.

This is the part about having to run anaerobically to increase aerobic capabilities that I agree with you about. To have the same effects on intermediate fibers that we do on slow twitch we must run anaerobically, but we can still be smart about the training.

To train capillaries in intermediate fibers we must do reps at 1500m pace or you can do long hill reps at 1500m-3k effort. To increase mitochondrial density in intermediate fibers you have to run at 5k-10k pace.

So obviously you don't need to do the full range of "aerobic work" for every event. You need to the type that is more relevant to your event.

Essentially I agree with you though. To get full aerobic development you do need to go anaerobic. The question is if you really need to or not.

I appreciate all the stuff you guys are explaining. But could someone recommend a basic intro to exercise physiology textbook? I'd like to have something that I can dig into.

I'm a dummy wrote:

I appreciate all the stuff you guys are explaining. But could someone recommend a basic intro to exercise physiology textbook? I'd like to have something that I can dig into.

Magness' Science of Running book has lots of physiology background info.

The following is somewhat "sciencey", so for those who hate physiology-talk on these boards, look away.

Humans don't produce lactic acid, so it certainly won't dissociate into lactate and H+ ions, as some people here have suggested. That is the biggest inaccuracy pertinent to the discussion here, and an inaccuracy that has been going on for too long.

We produce the lactate ion from the LDH reaction when the amount of reducing equivalents (NADH + H+) cannot be oxidized fast enough in the electron transport chain. So, NADH + H+ will reduce pyruvate (from glycolysis) into lactate. That is the LDH reaction. This occurs most during intense exercise. This reaction produces neither lactic acid nor H+ ions. In fact, it CONSUMES H+ ions.

We do produce H+ ion (acidity) from CO2 production, most of which will be buffered via ventilation, but the reason we get very acidic during hard exercise is due to the massive amount of ATP hydrolysis (breakdown) supporting the muscular contractions. ATP hydrolysis generates H+ ions, more than can be buffered at the time.

See Robert Robergs' paper on metabolic acidosis:

http://www.ncbi.nlm.nih.gov/pubmed/?term=robergs+

[au]+2004

Rod Munch wrote:

The following is somewhat "sciencey", so for those who hate physiology-talk on these boards, look away.

What are you trying to do? Kill the thread? Enough of real science already, this is letsrun damnit.