Ultrarunner Podcast Claims Bruce Fordyce better than Kipchoge

Camille I'm a big fan of yours. I would be honored to go for a run with you sometime and it would be great to go for a coffee with you. I want to get to know you.

Certain mental toughness? Like running a 2:01:40 marathon? Who is to say he hasn't had blisters all the time training on dirt roads at his home?

Back to the OP's point: So do most people on here not think that Kipchoge could go sub 4:50 for 50-miles on a flat road/track?

I totally agree that sometimes "flat out distance running speed" can be a sort of liability in ultra marathon races (esp for over 100km and with lots of climbing/duration). Sometimes the 2:20 guy beats the 2:08 guy. He probably has a better chance at 50-miles + though compared to a 50km for sure. Running Economy at more sub maximal paces is the name of the game....not Vo2max or lactate management.

But if we look at the bigger numbers and high correlations of data I'm pretty sure a 2:20 marathoner going to have a lot of advantages and more likely outperform the 2:40 marathoner....even at an ultra long distance race (on a flat uniform surface). So it is really that much of a stretch to say that the 2:01 marathoner probably has some ultra marathon potential over the 2:20 marathoner?

Is a 50-mile really that much different from a 50km in terms of physical demands and energy systems being used? People get caught up on "twice the race distance!"...but would you tell a fast 5km runner that they probably won't do well in a 10km because it is "twice as long."? Similar energy systems. We've already found with a lot of endurance events and performances that you don't even have to slow down your pace that much to run twice the distance!

I agree. The difference between a 2 hour maximal effort and a 3+ maximal effort is not linear for most (let alone 4+). If you think of it as a pace-duration curve, individual variability is high. Just because a runner's maximal 2 hour sustained pace is high, does not mean there will be an even reduction in the curve down to max 3 hour pace or max 5 hour pace. Just based on Kipchoge's marathon time and log of training paces you could estimate his aerobic threshold around 5:20-5:24/mi pace. *In theory* one could predict this is what could be run for 50 miles. But there are too many other factors to consider at that point. To just say someone could run that pace because it looks good on paper doesn't cover it. When the clock turns over 3-4 hours things can change. Fuel utilization, running mechanics, fatigue resistance are big factors in how long someone can sustain what is an easy pace for them. This could be trained, and he may even be able to run faster than 5:40/mi for 50mi. But we would never know unless he trained and went for it. Also like Sage mentioned, variable running economy at different paces. I don't see a whole lot of running between 5:40 and 5:20 pace in his training logs that are available, and zero sustained running at that pace. To just bounce off his marathon training and head right out the door for 50mi would not guarantee his best possible time. Is it possible he could beat the record right now? Maybe. He likely won't try. Is it possible he could fail on the first attempt(s), train specific and then go and crush it? Maybe. He likely won't try. Is it possible he will head into a lab and perform some muscle biopsies and event-specific fuel utilization and O2 testing for this thread? Not likely.

I think Kipchoge could do a really fast 50 miler. BUT it's all talk until it actually happens. 50 miles and 100k are a lot longer than an Marathon. The added time is a lot more than going from 5k to 10k which are less than 15 minutes for these great runners.

Running 5-6 hours and you add a whole new set of problems. Nutrition, blisters and weather are probably the most important once.

"So it is really that much of a stretch to say that the 2:01 marathoner probably has some ultra marathon potential over the 2:20 marathoner?"

Yes it is. The 2:20 -2:30 marathoner who moved up to ultras is just one of many 2:20-2:30 marathoners who didn't move up. You have to be attracted to the longer distances and then it might work out or not.

I think the conclusion that a 2:15 marathoner would be a lot better than a 2:25 marathoner in ultras is wrong. I base that on reality. Yiannis Kouros had a 2:25ish Marathon best. He might have done a little better if he would have tried but he shifted to ultras in an early age.

But he didn't and instead he set ultra records which might stand in 25 to 50 years time.

Former world class ultrarunner Rune Larsson wrote a great piece about this topic:

http://www.loparlarsson.se/articles-in-english/speed-and-ultradistance/

S. Canaday wrote:

Is a 50-mile really that much different from a 50km in terms of physical demands and energy systems being used? People get caught up on "twice the race distance!"...but would you tell a fast 5km runner that they probably won't do well in a 10km because it is "twice as long."? Similar energy systems. We've already found with a lot of endurance events and performances that you don't even have to slow down your pace that much to run twice the distance!

Bingo. Once you are above 3 hours, the difference in energy systems is very small. Individual differences at that point are decided by genetic factors such as muscle fiber make-up and body mechanics, internal drive (motivation), and training specificity. Every hour beyond 4 hours, the importance of these factors increases.

S. Canaday wrote:

Is a 50-mile really that much different from a 50km in terms of physical demands and energy systems being used? People get caught up on "twice the race distance!"...but would you tell a fast 5km runner that they probably won't do well in a 10km because it is "twice as long."? Similar energy systems. We've already found with a lot of endurance events and performances that you don't even have to slow down your pace that much to run twice the distance!

Yes, it is. I cited 50K WR holder/South African, Thompson Magawana, only had a best of 5th at Comrades (his only top 10 finish in 3 tries). No amount of money and prestige could help to elevate him. Watching several marathoners step up at Two Oceans this yr (56K, closer to marathon pace), they started to crack around 42-50K, probably around the point of glycogen depletion and the shift in greater slow twitch fiber recruitment.

In a marathon, you've got a max of 20-22 mi of stored glycogen and can take some gels/drink to get you through the final few miles, no problem. For 50 mi and beyond, you're going 15+ more miles beyond the glycogen depletion point. It's played out over and over again how critical this period of longer depletion and how the slower marathoners have unique traits to overcome the faster marathoners.

Camille, really appreciate your posts and of course greatly respect what you have done at Comrades and the 100-mile etc.

However, I don't understand your point on stored glycogen and these distances of depletion in an ultra? Many people (regardless of pace/intensity) will "hit the wall" and run out of stored glycogen at mile 20-22 of a marathon. It is a simple work output. We're always riding the line thin line of bonking in the latter stages of an ultra or marathon if we are pushing hard.

Now a well trained (high mileage runner and long run adapted to burn fat as fuel more efficiently) athlete who paces themselves well in a marathon/ultra wants to just "brush up against the wall" ideally. Of course this only happens when one executes a very good race. Despite running at sub maximal paces and trying to utilize a high % of body fat to burn as fuel they are generally also taking in carbs during the race so that they do not go hypoglycemic. Didn't you even have some beer in your 100-mile record?!

In my mind whether one "hits the wall" at mile 16 or mile 48 depends on: how well trained they are, how well they are managing their intensity/pace, how many calories/carbs they are ingesting during the event, and how efficient their running economy is at different points in the race. Of course with sheer muscle failure or something like dehydration this can alter form to become very inefficent and cause debilitating cramps/stomach issues.

I think Comrades are Two Oceans are more likely to throw some "Fast marathoners" for a loop because they have significant hills. Some runners are definitely not as good at climbing. We use Comrades because it is one of the fewer ultras where a decent number of sub 2:20 marathoners (and sub 2:40 for women) have raced....and because it is not on a trail. I think 50-miles/100km on a flat track/road would have a better conversion for the super fast marathoners.

And to the Forest Gump poster: Dude you are obsessed with these "blisters" as a limiting factor?! Get a well fitted shoe, some of my Drymax "Sage Runner" socks and lube up with some Squirrels Nut Butter and you don't have to worry about blisters anymore!

The sample size is really too small to know. Yes, some “slower marathoner” have beaten guys that were faster marathoners. That happens as you move up in every event. I beat guys in a 10k that beat me in 5k.. but then a lot of other guys beat me in both. Ultra runners don’t necessarily have unique traits... they just actually train for Ultras.. do some quick research on fuel utilization... it’s pretty trainable. Heck even just changing your diet to high fat for 3-5 days has been shown to increase the percentage of fat you burn at a given intensity. Adjusting your diet and training methods can greatly influence you fuel utilization as evidenced by 100’s, probabaly 1000s of studies.

Plus, running economy at specific paces is also trainable. So these fast marathoners don’t have ideal fuel utilization and specific running economy for 50+ mile races.. several posters have mentioned this and they are absolutely correct. But they’re training for a marathon so they shouldn’t. If they train for a 50 miler (including dietary changes and stride modifications) a handful (not all) would make the adaptations necessary and would beat the ultra guys (just like they did at every event from 800-Marathon). But right now the percentage of sub 2:12 marathoners that seriously (and correctly) train for 2+ years for Ultras is insanely small. Almost 1900 guys (according to iaaf) have broken 2:12. Name 19 (1%) that have seriously and correctly trained for a 50+ mile race.

And to follow up: If the "depletion point" in a 50-miler is at mile 35...then what is the "depletion point" in a 100-miler? Mile 65? Mile 80? On the trails people seem to bonk pretty bad (even at like mile 40 in a 100) and then they eat something and are able to run fast again.

S. Canaday wrote:

And to follow up: If the "depletion point" in a 50-miler is at mile 35...then what is the "depletion point" in a 100-miler? Mile 65? Mile 80? On the trails people seem to bonk pretty bad (even at like mile 40 in a 100) and then they eat something and are able to run fast again.

This whole depletion thing is influenced by pace and training. By consuming a mix of fructose/glucose you can digest 90g of carbs per hour.. (some cyclists have been shown to get close to 120 g/hour). So if you race a 50 miler in 4 hr. 30 min, you have about 4 hours or so to get carbs in. So 90x4 is about 360 grams of carbs (realistically highly trained elite athletes could digest more but 90/hr. is the average in research. Let’s say a person starts with 500g of muscle glycogen (again highly trained elites may have more). So 860 grams of carbs. You can completely run out so you have 800 grams to work it. That’s 3200 calories. One mile= 100 calories *for the average population.. a lightweight highly efficient athlete would burn less). So using all of these conversative numbers you have 32 miles that can be fueled solely by glycogen.. or 64% of the race. The other 36% will rely on fat. That’s not that crazy and a couple trips to a lab will help these crazy fast elites determine a proper pace based on fuel utilization.

50 miles just isn’t that long and doesn’t require super unique traits for fuel utilization as long as you know how to train. 100 miles may be a bit different though.

Delusional ultrarunners? wrote:

Just heard that Ultrarunner Podcast's Eric Schranz claimed that Kipchoge would not be able to break Bruce Fordyce's 50 mile work record (4h 50min, 5:48/mile...). Kipchoge could run a 4:2x 50 mile easy. Even Jim Walmsley who is far from an elite marathoner could probably break the 50 mile WR if he really tried.

Are ultrarunners really this dellusional to what kind of talent and ability someone like Kipchoge/Bekele has?

Kipchoge could not break it. He's smart enough to never try.

Ultra-marathoning is a form of mental illness. So they are by definition delusional.

I'm talking about the ability to cope with "the bonk". The bonk is inevitable in ultras. Someone who's more slow twitch and a better fat metabolizer is better able to cope with it and continue to maintain a high intensity without fatiguing and breaking down to the same extent. I don't think whether there's hills or not really matters cause the bonk is still going to happen, and if anything a flat course is harder cause of the likely faster pace and more repetitive stress and strain.

ahhhh ultras, the hot dog eating contest of the running world.

sure it's terrible and of extremely of low quality, but darn it there sure is a great quantity!

all that's missing is joey chestnut.

jaguar1 wrote:

I'm talking about the ability to cope with "the bonk". The bonk is inevitable in ultras. Someone who's more slow twitch and a better fat metabolizer is better able to cope with it and continue to maintain a high intensity without fatiguing and breaking down to the same extent. I don't think whether there's hills or not really matters cause the bonk is still going to happen, and if anything a flat course is harder cause of the likely faster pace and more repetitive stress and strain.

*Absolute Pace doesn’t determine fuel utilization- Intensity does. So a faster pace on the flats can still lead to a higher percentage of fat being burned because the intensity (or oxygen consumption) is lower. *However uphills have less impact so you’re right that uphills could limit muscle damage. But most races with uphills have downhills and the net effect usually causes more muscle damage than ‘flat’ only.

And again, you can train fat utilization, and it’s not as much of a factor in a 50 mile race which is what this thread addresses. 100 mile + races and you have to be a fat-burning machine and “fat-burning” genetics (don’t know what they are but I’m sure they exist) will play a larger role.

I don't think the "bonk" is inevitable. It usually happens though because we are pushing our limits and riding that fine line with taking in carbs, burning fat, and managing possible stomach/digestion/dehydration issues with our caloric intake on the run.

I could go out and run a fairly relaxed 2:35 marathon as a training run (take 2 gels) and not bonk. If I tried to race another sub 2:20 marathon though, there is a good chance I would positive split the last 10km and maybe I would epically "bonk" at mile 22....and start running over 6:00/mile pace even after taking in 4 gels along the way.

Now I can only speak from personal experience of racing a lot of 50-mile-100km events on trails/mountains...but there is a common occurrence were runners who go out too fast tend to "bonk" and slow down exponentially after 20-22 miles (sometimes earlier if it is a hilly course at altitude). It doesn't matter if it is a 50km or a 100km. Usually they aren't fueling properly and have been running at too high of an intensity relative to their fitness level. Maybe they push a big 3000' climb and don't take any gels or something. There is a certain work output we can calculate and compare it to our relative efficiency (Running Economy).

But if someone wants to "just finish" an ultra efficiently and they run it very controlled and take in plenty of carbs during the race...then I think they can make it without totally running out of glycogen and "bonking." Realize when I say "bonk" I mean going hypoglycemic and having to slow down a lot.

With mountain/hilly ultras the limiting factor is often sheer muscle fatigue (quads that blow out on the downhills etc.) and cramps (which may or may not be caused by dehydration). If people are eating enough, managing their pace, and not getting stomach distress than they should be able to not go hypoglycemic. Whether or not their "legs hold up" or they are able to keep their body core temp cool (or warm enough in cold conditions) can be another limiting factor though.

[quote]c7runner7 wrote:

Yep, intensity. The cardiovascular effort is the same (~80% of HR max), but the pace is different-- on road you'd hit the point of glycogen depletion sooner. Hills change up the muscle usage. Even just 1 good hard hill session to the point of muscle fatigue is protective for wks-months. As someone else characterized, running a nearly flat course is almost like if you were running the whole thing downhill cause you're in the same repetitive muscle usage and footstrike.

For fat utilization, your muscle fiber % is fixed at birth, and then you develop what you have. A sub 2:05 marathoner who has more fast twitch fibers is going to be at a disadvantage no matter how fat adapted they try to become. Once the glycogen is depleted, they simply don't have the slow twitch fibers to shift to fat metabolism.

Sage, you don't really bonk in a marathon if you're fully glycogen replete and take a few gels/drink to get through the last few miles. For an ultra, you absolutely deplete your glycogen no matter what. You're going far beyond glycogen depletion. If you don't have as many slow twitch fibers and aerobic adaptations once the metabolic shift happens it's going to be a struggle. You're only topping off with gels/etc. as a quick energy source. Otherwise the energy demands exceed what you can consume, so you're relying on your own fat metabolism.

Wow, so is it true that Alberto Salazar is the fastest 5000 runner to ever race Comrades and he WON?

There goes the theory that fast guys can't win ultras.

"Sage, you don't really bonk in a marathon if you're fully glycogen replete and take a few gels/drink to get through the last few miles."

Hey Camille! Big fan.

I think both you and Sage are correct that not every fast marathoner is going to make a great ultra runner, but I would personally not bet against Kipchoge smashing the 50 mile record if he decided (for whatever reason) to do it.

There's obviously some correlation between being a good marathoner and a good ultra runner, and Kipchoge is the undisputed best marathon runner ever, and it's not even close.