I'd love to see anyone stick a 30 ft dyno, 120lb or not

I'm gonna go out on a limb and think that any climber, working a route at their limit is probably burning similar amounts of calories.

Put it this way: When I was a fatty, just trying to make it up a 5.7 would make my hear pound, my palms sweat and I'd be out of breath 4 or 5 moves in. Now I have more muscle, less fat and actually last a hella lot longer on 5.11s than I did on those 5.7s. I'd almost say I burned more calories struggling up those easy routes than I do now on the harder ones.

Not scientific, but just an example of personal experience.

Probably not as impressive as a 150 foot offwidth. Commas and punctuation are over rated - especially in the middle of a rant.

You are going to have a hard time convincing me that a 120b pound kid pink pointing a 30 foot dyno, dyno, done 14 in < 1 minute is using more calories, using more calories per unit of body weight or using more calories per unit of time than a burly dude lugging a rack of Bigbros up a 150 foot offwidth 12. You are way overestimating the effort involved and further muddling it with vague lifestyle assumptions.

Sure, I'd like to know what you think.

When I consider this difference in my mind I think of a few different things.

1. 5.14 climber climbs one 5.14 and 5.12 climber climbs one 5.12, what's the difference in calories burned?

2. 5.14 climber, on average, has more muscle than 5.12 climber, more muscle burns more calories even when not climbing.

3. 5.14 climber climbs more days/year and climbs more climbs/day=more calories burned.

OK. Here goes.

Bertuzzi et al¹ found that highly skilled climbers burned 17.1, 19.3, and 22.0 kcal climbing a single 10-m gym route rated 5.10, 5.11, and 5.12, respectively. Let's assume that the average outdoor route is twice as long (20 m) and that the energy expended is proportional to the length of the route. Then climbing the average outdoor route burns twice as many calories as the average indoor route. Now, from just three data points it's difficult to determine the true relationship between route rating and calories burned, but an exponential relationship seems like a reasonable guess, and as it turns out, fits the data well. Fitting our exponential model and extrapolating to 5.13 and 5.14 shows the following:

[img]http://jt512.dyndns.org/images/kcal.rating.png[/img]

The model predicts that climbing a 5.14 route burns 56.5 kcal, just 12.5 kcal (28%) more than a 5.12 route.

Now let's assume that a climber climbs 10 routes in a typical climbing session: 5 routes at his limit and 5 routes at the next lower number grade. Then a 5.14 climber burns 532 kcal climbing per session, compared with 413 kcal for the 5.12 climber—a difference of 119 kcal.

Now back to the "night and day" analogy. You said that the difference between climbing 5.12 and 5.14 is like the difference between night and day. Now the actual difference between night and day is 12 hours, and a typical 5.12 climber probably burns about 3000 kcal in a typical climbing day. Then a typical 5.14 climber would burn 3119 kcal in a typical climbing day, about 4% more. Four percent of 12 hours is 0.48 hours (29 min), which turns out to be embarrassingly close to a half-hour, my completely off-the-wall guess.


This is directly answered above.


I'm not sure that's true.


That's almost certainly true, and I did not take that into account. If you factor in the amount of energy a 5.14 climber has to burn training to maintain his climbing level, compared to what a 5.12 climber has to do, then yes, there will be a bigger difference.

Jay


¹ Bertuzzi RC, et al. Energy system contributions in indoor rock climbing. Eur J Appl Physiol (2007) 101:293-300.

So, one 5.14 requires 28% more calories than one 5.12, correct?

If you take that 28% and you add to that that a 5.14 climber climbs more days/year more climbs/day and that a 5.14 climber has more muscle, even if that made a minor difference, couldn't we be close to 50% more total calories burned/year from climbing?

If that's accurate or thereabouts, a 5.14 climber could eat approximately 40-50% more calories than a 5.12 climber w/o gaining weight.

How are you going from a 28% difference in calories burned on a single climb, then say the 5.12 and 5.14 climber each climb ten routes/day, and conclude that the difference in that day is only 4%?

Another thing is that the climbers doing the climbing are skilled, right?

I feel like it it safe to say that a .11 climber's technique is going to be a lot worse then a .14 climber's technique, so they will likely use more energy in doing a route from making inefficient moves.

Seems like that could tilt the chart towards people climbing easier routes not burning as much energy.

Just a thought.

As someone who is 6'3" and rail thin, your son sounds way too skinny.

you could do that, in a thought experiment, but jay was using numbers from a study where they actually, you know, measured it. (albeit a small sample size.)

Right.


That seems reasonable.


No. We're saying that he burns 40–50% more calories climbing than a 5.12 climber, that would be a total of 413 kcal × 150% = 620 kcal/day burned from climbing, or a difference of 207 kcal/day. So, that's how much more he could eat per day than the 5.12 climber: about 1 PowerBar.


I explained that in my previous post. If you assume (reasonably) that the 5.12 climber burns 3000 kcal/day total (413 kcal of which is from climbing), and the 5.14 climber burns 28% more energy climbing, then he burns 532 kcal/day climbing. That's only 119 kcal/day more than the 5.12 climber, so the 5.14 climber burns 3119 kcal day: 4% more.

Jay

Another thing is that the climbers doing the climbing are skilled, right?

I feel like it it safe to say that a .11 climber's technique is going to be a lot worse then a .14 climber's technique, so they will likely use more energy in doing a route from making inefficient moves.

Admittedly, I'm not as smart as some of you nor put this much mathmatical thought into my diet or training. So for my simple mind, I'm skinny climb as hard as I can eat before I go and eat when I'm done. And yet I am still skinny. I feel strong don't look strong. Does all this math really help? And after doing all the before a meal doesn't that ruin your appetite? Seriously this just confused the sh*t out of me . If I followed at all the gist is I'll have to eat more carbs as I progress in grade levels to not burn out quicker. Is that about right?

Carbs should make up most (60%) of your energy intake, and most of them should be low GI (slow release), you should get enough protein (this should be 25% of your calorie intake) and lastly fat should be around 15%. All of these are rough figures.

Where are you getting these numbers from? They're quite similar to my recommendations for weight loss, but they're not what I'd recommend for long-term weight maintenance in general, much less to someone who (as best I can tell, given his grammar and punctuation) thinks he's too thin. First of all, your protein recommendation is too high. I'm not aware of any literature to support your recommendation, and the long-term health effects of such high protein intake are unknown, AFAIK, and potentially detrimental. Secondly, why only 15% of calories from fat? What's wrong with (much) higher fat intake, assuming it's primarily from plant oils?

The rest of your post seems pretty reasonable.

Jay

Bertuzzi et al¹ found that highly skilled climbers burned 17.1, 19.3, and 22.0 kcal climbing a single 10-m gym route rated 5.10, 5.11, and 5.12, respectively. .
.

Thia could be the root cause of some of the issues. Are these "highly skilled" climbers the same or different. If they are all 5.12 climbers it is pretty intuitive that they will work less hard climbing things below their limit. How hard does the my-limit-is-5.10 climber burn on a 5.10? about the same as any other climber climbing a route at their limit. All the fancy graphs and extrapolations don't make up for flawed assumptions,

Lies, damned lies and statistics.

Seems obvious that a better formula (than grade of the climb) to determine calories used on a route would take into account the muscle groups used (why off-widths are going to use more then those nancy-boy crimpfests thar the sportos like) , the length of time on the route, maybe heart and respiratory rates..