the aerobic engine (mitochondria) and those nasty fast twitch fibres



teebone

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Oct 9, 2006
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Originally Posted by danfoz .


I bonked bad on a ride far from home after getting separated from my riding partner and realizing I'd left my wallet in his car. I crawled (literally) into the parking lot hallucinating mildly, eyes rolling in my head, a frothing, pleading mess, begging the parking lot attendant for money for a coke and candy bar from the vending machine. I believe I may even have clutched his shirt in my desparation. I do remember a look of horror on his face as he threw money at me while struggling to get away, but that could have been partly hallucination.

If there had been any rotten apples on the ground I would have been all over them. Two hours at redline without refueling and it can (meaning it will) happen to you. Nowadays I never leave home without an emergency energy gel in the kit.
Dan....a $10 bill in the saddle bag is also an essential. Never touched until necessary. "Break glass in case of emergency". :)
 

edd

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Never weigh myself, I know I'm always going to be to heavy !

I went on alone 100k (62 mile) ride back in the 1070s when I was young and not bike fit (use to commute short distances). I bonked 10ks from home, Legs just went to jelly, couldn't even walk properly. If I only knew I just need to eat something.

These days with all the gels and energy bars and nutritional info around, one should not be bonking !
 

edd

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Originally Posted by daveryanwyoming .


I agree with the overall gist of your post but in addition to Tony's comments, the points above are pretty misleading.

Blowing up is a short term fatigue of key systems things and can happen just as easily by trying to overpace a 40K TT and blowing up before the finish or a five minute bridging effort as it can in a short intense L6/AWC burst. IOW, you can just as easily blow up during primarily slow twitch sections or primarily fast twitch sections and it has a lot more to do with specific fitness for the type of effort and pacing than the muscle fiber type.

And as you acknowledged above, Bonking is a fuels management, primarily glycogen and blood glucose fuels management issue, I guess you could say it's a slow twitch thing from the standpoint that it's a longer term issue and you can't really bonk in a minute of hard effort unless you were already seriously glycogen depleted, but again tying it to muscle fiber makeup misses the point.

FWIW, in some sports nutrition circles they further differentiate bonking and hitting the wall. The former being an acute shortage of blood glucose to the brain with the resulting mood shifts, irritability, tunnel vision, sense of doom, etc. The latter being depletion of muscle glycogen and inability to fuel muscle contractions primarily via sugars. They're often but not always connected to one another. IOW, it's possible to bonk with legs that still have plenty of glycogen on board but you're not currently fueling your brain and it's possible to have enough blood glucose and liver glycogen to feed the brain adequately but the legs are depleted. That can happen during periods of frequent hard and long training and racing when the rider isn't keeping up with glycogen resynthesis, blood sugar can be all right since you can get blood sugar up very quickly by eating on the bike but muscle glycogen stores can be depleted from previous work and glycogen synthesis is a slower process. Anyway, interesting take on things and not how I previously thought about bonking on the bike.

-Dave
[COLOR= rgb(24, 24, 24)]Fair enough comment - I painted this thread with broads strokes as I wanted it to be as less confusing as possible. You stated it misses the point. So what is the point ?[/COLOR]
 

Felt_Rider

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Oct 24, 2004
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I had my first near experience of bonking and it fortunately happened years ago in my first ever club ride that was full of older veterans of cycling, but was also the older aged slower club level. I had many years of being able to train at the gym on an empty stomach as they say so when I attended this first 40 mile ride I went with barely eating any pre ride meal, did not bring any solid or liquid carbohydrates on the ride. I just had no idea what was required. About 10 miles from the end I had that sensation I could not go any further and I really could not. How that group of veterans seemed to be so patient and understanding as well as sharing their food with me was an experience that I will never forget and never made that mistake again.

Skip ahead to current day I am far to the other extreme carrying way more than I ever use. I now have a habit of carrying almost as much supplies with me on a 30 mile ride as I do on a self sustained 100 mile ride. I have the same 2 - $10 bills in the saddle bag never used as teebone suggests for years. When I finish I typically have quite a few items still in my jersey pocket, but there are many times that I have been able to pay it forward with being able to share tube, air cartridge, gel or cliff bar with someone that thought they could play the minimilist.

On occasion I will give a rebuke (like you know better) to the experienced person that came out to a 60+ mile group ride intentionally with 1 water bottle, no food and no saddle bag, nothing in their pockets with intention that they could be lighter than everyone else and have a better chance at a stupid KOM on a club ride, but for most those that make a newbie mistake having the experience is enough to make a good reminder to come equipped for things that do happen out on the road. (The exception being an event that has sag stops and support vehicles, but personally I still prefer to carry my own supplies and prefer to eat food that I know will not upset my stomach)

What I have been impressed is a few random times someone would break a cable and someone else in the group would say, "I've got a spare cable in my bag." Now that is impressive. /img/vbsmilies/smilies/smile.gif
These days I do a lof of my training solo so it is very important to be equipped with double the supplies and a phone. For training I go by a watt is a watt so how much I weigh and how much the bike weighs is not near as important to me as going out and coming back safely while maitaining those training goals. Racing would obviously be different.
 

daveryanwyoming

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Oct 3, 2006
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Originally Posted by edd .
...[COLOR= rgb(24, 24, 24)] You stated it misses the point. So what is the point ?[/COLOR]
Well my point in the response above was that neither of these things are directly attributable to a rider's percentages of fast vs slow twitch muscle fibers so attributing blowing up or bonking to muscle fiber types is misleading.

But from what you posted the main points seem clear and were stated above but to be explicit might be something like:

- If you blow up you either lack the specific fitness for the effort or are pacing poorly.

- If you bonk you are not managing fuels well on or off the bike and or are pacing poorly for your current fitness.

But either of those things can happen to riders that lean towards the fast twitch or slowtwitch ends of the spectrum and blowing up can happen in very short primarily anaerobic efforts or in very long primarily aerobic efforts.

-Dave
 

vspa

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Jan 11, 2009
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edd said:
Never weigh myself, I know I'm always going to be to heavy ! I went on  alone 100k (62 mile) ride back in the 1070s when I was young and not bike fit (use to commute short distances).  I bonked 10ks from home, Legs just went to jelly, couldn't even walk properly. If I only knew I just need to eat something. These days with all the gels and energy bars and nutritional info around, one should not be bonking !
even with correct nutrition an unprepared rider will suffer in that distance,
 

vspa

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Jan 11, 2009
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edd said:
Having been away from this forum for a good while, I was kinda weirded out that ten years on the discussions on training are still pretty much the same. I started this thread in the hope that I and others can shed some light on some basic underling principles.
checkout the powermeter subforum, most of the new findings and methods are underlined there, or the its killing me thread on this one,
 

JibberJim

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Aug 25, 2009
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Originally Posted by Felt_Rider .
What I have been impressed is a few random times someone would break a cable and someone else in the group would say, "I've got a spare cable in my bag." Now that is impressive. /img/vbsmilies/smilies/smile.gif
I was quite surprised when I joined a ride in a completely flat part of Canada, where there's no issue with carrying as much weight as you want - that when someones chain went, I was the only person (other than my wife...) with a quick link or a chain tool, despite the fact I was carrying less than normal being a long way from home. Not everyone on the ride even had puncture stuff with them. Friendly enough group that it didn't matter when there was a puncture, but it didn't even seem to be worth a mild rebuke.

At home the 1.5kg saddlebag I ride with may well be hurting me in the Strava KOM stakes, but phoning to be rescued or walking home is a real PITA.
 

edd

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Jul 8, 2003
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Originally Posted by vspa .


checkout the powermeter subforum, most of the new findings and methods are underlined there,
or the its killing me thread on this one,
Cool, I will
 

edd

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Originally Posted by daveryanwyoming .


Well my point in the response above was that neither of these things are directly attributable to a rider's percentages of fast vs slow twitch muscle fibers so attributing blowing up or bonking to muscle fiber types is misleading.

But from what you posted the main points seem clear and were stated above but to be explicit might be something like:

- If you blow up you either lack the specific fitness for the effort or are pacing poorly.

- If you bonk you are not managing fuels well on or off the bike and or are pacing poorly for your current fitness.

But either of those things can happen to riders that lean towards the fast twitch or slowtwitch ends of the spectrum and blowing up can happen in very short primarily anaerobic efforts or in very long primarily aerobic efforts.

-Dave
Well stated /img/vbsmilies/smilies/duck.gif
 

edd

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Jul 8, 2003
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True or false ?

1) When we go the gym and and train in the eight to fifteen rep range with the aim to train the muscle to failure we stress fast twitch muscle fibres that respond by growing thicker (hypertrophy), we get big muscles.
Or alternatively we train for 30 reps or possibly for even 10 minute to build some endurence. The adaptation part occurs in the rest/recovery period directly after training.


2) When we train at long very easy constant cycling pace for one or more hours (base building), we build the aerobic ability (mitochondria) in our muscles durring the exercise. This aerobic ability begins to diminish as soon as we get off the bike.

3) When we put in hard longish efforts on the bike we experience a bit of both.
 

daveryanwyoming

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Oct 3, 2006
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Originally Posted by edd .

True or false ?

1) When we go the gym and and train in the eight to fifteen rep range with the aim to train the muscle to failure we stress fast twitch muscle fibres that respond by growing thicker (hypertrophy), we get big muscles.
Or alternatively we train for 30 reps or possibly for even 10 minute to build some endurence. The adaptation part occurs in the rest/recovery period directly after training.


2) When we train at long very easy constant cycling pace for one or more hours (base building), we build the aerobic ability (mitochondria) in our muscles durring the exercise. This aerobic ability begins to diminish as soon as we get off the bike.

3) When we put in hard longish efforts on the bike we experience a bit of both.
Literally as written I'd say:

1) False

2) False

3) False

With the devil being in the details. Muscle hypertrophy from lifting weights that are a substantial percentage of our one rep max isn't limited to just the fast twitch fibers

Aerobic ability does not peak during the workout and begin to immediately decay as soon as we get off the bike. Many of the adaptations also happen during recovery. We generate new cells all the time and if we've been applying enough but not too much stress those new cells adapt towards greater fitness. That applies to endurance training as well as strength training though the adaptations are quite different.

Hard longish efforts on the bike in general have almost no maximal strength or hypertrophy effects. In general because I'm sure someone can point to a study of severely atrophied people who underwent substantial muscle hypertrophy through low force riding but cycling forces even at very high power are a very low percentage of one rep max strength for healthy adults and the hypertrophy related from vastly submaximal very high rep activities is very minimal if at all. Think about a three hour ride at 90 rpm that's over 16,000 reps, think about how little hypertrophy you'd experience by going into the gym and doing 16,000 reps of a weight light enough to actually pull that off, don't expect to gain a lot of muscle mass on that program but if you do it quickly and continually enough you may gain quite a bit of aerobic fitness and sustainable power.

-Dave
 

edd

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Originally Posted by daveryanwyoming .

Aerobic ability does not peak during the workout and begin to immediately decay as soon as we get off the bike. Many of the adaptations also happen during recovery. We generate new cells all the time and if we've been applying enough but not too much stress those new cells adapt towards greater fitness. That applies to endurance training as well as strength training though the adaptations are quite different.

Hard longish efforts on the bike in general have almost no maximal strength or hypertrophy effects. In general because I'm sure someone can point to a study of severely atrophied people who underwent substantial muscle hypertrophy through low force riding but cycling forces even at very high power are a very low percentage of one rep max strength for healthy adults and the hypertrophy related from vastly submaximal very high rep activities is very minimal if at all. Think about a three hour ride at 90 rpm that's over 16,000 reps, think about how little hypertrophy you'd experience by going into the gym and doing 16,000 reps of a weight light enough to actually pull that off, don't expect to gain a lot of muscle mass on that program but if you do it quickly and continually enough you may gain quite a bit of aerobic fitness and sustainable power.

-Dave
Ah yes, the devil is always in the details - aerobic ability is not only a very complex adaptation process, there are also individual who respond to aerobic training so successfully we may even describe them as unique and talented.

I'm only going to ask for some evidence that point 2 is false

Appreciating the fact that we all need to recover from fatigue and once we have recovered from the fatigue we a better than we were the last time we were on the bike and if we manage the mix of recovery and training stimulus we improve. I'm not arguing that this is not correct, of course it is. I simply make the point that the body is always trying to adapt to be energy efficient and the construction/destruction of mitochondria happens while we are on/off the bike.
 

daveryanwyoming

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Originally Posted by edd .

Ah yes, the devil is always in the details - aerobic ability is not only a very complex adaptation process, there are also individual who respond to aerobic training so successfully we may even describe them as unique and talented.

I'm only going to ask for some evidence that point 2 is false

Appreciating the fact that we all need to recover from fatigue and once we have recovered from the fatigue we a better than we were the last time we were on the bike and if we manage the mix of recovery and training stimulus we improve. I'm not arguing that this is not correct, of course it is. I simply make the point that the body is always trying to adapt to be energy efficient and the construction/destruction of mitochondria happens while we are on/off the bike.
Well I don't know of any science that tells us exactly 'when' fitness happens but back out and think about some of the adaptations that we're targeting. Increased heart stroke volume, increased red blood cell count, increased capillary densities in the working muscles, increased mitochondrial densities in the working muscles. All of those things require tissue and or cellular regeneration and there are well defined time courses of adaptation for regenerating cells. While you're actually riding the bike new capillaries don't just pop up suddenly and then wither away when we stop pedaling those are changes that are relatively slow and require generating new tissue. Same for all of the big items mentioned above, heavy exercise does not instantly make new red blood cells appear but over time RBC count can increase given the right kind of stimulus and enough recovery time.

Sure there are likely some instantaneous changes as well such as hormonal or general blood chemistry, endocrine system changes and some of those could be quite rapid but that's not the big ticket items that we associate with greater cardiovascular fitness, greater aerobic fitness or increased sustainable power. Those things take time and I'll argue the vast majority of those changes actually happen after we get off the bike and not while we're actually applying the exercise stimulus that is the reason for the subsequent adaptations.

-Dave
 

bgoetz

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Wow, I really like this debate! If i read correct the two of you may have slightly different perspectives on this. So, given what you wrote above. Lets say my training program consists of 2 days a week of focused harder workouts where I repeat the same workout in the evening. I can typically complete both workouts, sometimes not. I have a job that induces minimal fatigue so I can rest well in between. Is there a chance that the second workout is still effecting recovery in such a way that if I were to only do the one workout per day I could see the same or better adaptation? Or if I am able to rest well in between and complete both workouts is the increased stress from the second workout more likely to result in more adaptation?
 

daveryanwyoming

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Originally Posted by bgoetz .

Wow, I really like this debate! If i read correct the two of you may have slightly different perspectives on this.

So, given what you wrote above. Lets say my training program consists of 2 days a week of focused harder workouts where I repeat the same workout in the evening. I can typically complete both workouts, sometimes not. I have a job that induces minimal fatigue so I can rest well in between. Is there a chance that the second workout is still effecting recovery in such a way that if I were to only do the one workout per day I could see the same or better adaptation? Or if I am able to rest well in between and complete both workouts is the increased stress from the second workout more likely to result in more adaptation?
Wow, if that's the debate going on then I've totally misread Edd's questions but that's a distinct possibility as I wrote that as I waited in an airport at the tail end of a travel day from hell and I was pretty punchy.

I took this question as 'when do actual adaptations occur' and I strongly believe they occur post workout not during the workout for the reasons listed. IOW, we stress our bodies with the work but it's when we get off the bike and recover that our bodies begin to adapt. Yeah, maybe that's too black and white as we're adapting every second of every day or IOW we're regenerating cells and tissue every second of every day and the question is whether that next batch of cells is just slightly better adapted to the stresses we're applying during training. But it takes an awful lot of new cells to see measurable improvement and that takes time as in days, weeks, months, and years. So from a practical standpoint we're not measurably fitter during the current workout but that fitness comes post workout(s).

So the part I was debating was the assertion that we are aerobically fittest as we step off the bike and then the fitness decays with time. That doesn't jive with my understanding of the time course of physiological adaptations or the general model of training stress, recovery, and super compensation.

But I don't see any of that as leaning towards single workouts vs. multiple daily workouts from a 'which is better for progress' standpoint but then maybe I'm missing something.

-Dave
 

bgoetz

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Well, I took your perspective that adaption occurs during recovery vs workout and applied it to something I have been pondering. So maybe in my own desire to gain a perspective on something I have been wondering I twisted they way I interpreted. But I read that you are saying adaptation primarily occurs during recovery. So one would say there could potentially be a point of diminishing returns to multi workouts per day as you are shortening recovery time by half, especially if you move into the next day with an a.m. workout or even another two a day. However, on the flip side adaptation requires stress which this type of schedule is applying a more of. I guess I was not looking for right, wrong, or otherwise. I think the answer may be that if you are not riding yourself into oblivion you must be recovering and therefore from your perspective adapting. Really the whole stress/recovery/adaptation thing is what hooked me and it seemed that there are two logical minded individuals who may have slightly different perspectives to what plays a larger role stress or allowing your body to recover and adapt. Sorry if I attempted to steer the thread off track.
 

daveryanwyoming

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I see where you're coming from but I guess my perspective is that the time scales of adaptation are much longer than days so whether you do one long workout on a given day vs. split workouts on the same day don't really change things when the adaptations to that particular day's workouts occur over many days or weeks. Realistically it doesn't seem possible to track what adaptations map to a particular day's workout(s) when someone is engaged in a regular training program but conceptually I doubt it matters whether you split or go long from an adaptation standpoint though it can matter from a recovery standpoint if for instance you try to do many split morning/evening days in a row and struggle to recover sufficiently from the evening work as you set out to do the following morning's work.

If adaptation time frames were on the order of hours it might make a difference but that's the part I don't agree with considering the typical time course of adaptations on the order of 6 weeks or so to adjust to a manageable step function increase in training stress. IOW, IIRC it's pretty well accepted (or at least I've come to accept) that it typically takes about 6 weeks to adapt nearly completely to a reasonable step function increase in training stress and it's typically modeled as an exponential response over that time frame. That's not the same as trying to pin down adaptation times to a single dose of training stress but it still indicates that these processes take a lot of time which is consistent with things like healing time from injuries and other processes that require generating new tissue and new cells, we can't rush that part of the process.

As I'm writing this I realize that Bannister's impulse response model which is the basis for the PMC and things like CTL and ATL effectively tries to model the adaptations due to singular doses of training, how well those models have been empirically verified on the per workout level as opposed to the overall training effect and overall fatigue level is something I don't know.

-Dave
 

quenya

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Jan 14, 2010
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Looking at the PMC I can see where one might be led to believe that fitness begins to decay as soon as one steps from the bike, because the CTL (or LTS in skiba's terms) behaves that way and CTL for better or worse is often equated to 'fitness.' IME a big training stress one weekend with a lighter than average week leaves me riding well a week later, once the fatigue has subsided, but I often find I'm really flying 2 weeks after a big weekend or big challenge ride even if I'm not as fresh as the prior week. I know that 2 weeks is less than the 6 weeks generally Dave mentioned (and has valid science/physiology whereas I have anecdote...) but I think these may be adaptations that happen in a shorter time frame that get lost in the 'wash' of a whole 6 week training cycle.
 

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