UKC

I've done a few long bouts of exercise over the last month that have, through bad planning of what I've been eating, left me completely wiped out. One was a climb on the Ben where I basically forgot to eat, one was a big yoga then circuits session where I hadn't got anything to eat, and yesterday was a 3 hour boulder session followed by a surprise 18 mile run. It used to take me days to recover from going to completely empty but I seem to be coping much better with it now.

So... is going to the point of bonk a way of training your body to adapt to this, and is it worth it (definitely doesn't feel like it...)? Is it mental or physical adaptation, or both?

In reply to Mr Fuller:
you did 3 hours bouldering followed by 18 mile run; all on an empty stomach? I think you should stop doing that man, its pretty good for you to atleast have some thing for your body to call upon.

In reply to Mr Fuller: wow, I have done that once were I ran out of fuel in the lakes in winter, I just had to stop and rest got the full on hypo shakes an all. Can't say I'd want to repeat the experience myself.

In reply to Mr Fuller:

Though I have no qualification to answer this, I imagine it depends what you're completely empty of. If it is energy and sugars, you'll burn fat. That is normal and healthy, though if you are completely fat-less your body starts destroying muscle. But if you are low on sodium/minerals/stuff you can probably hurt yourself. If I don't eat enough I sometimes feel dizzy and things, which means I wouldn't be willing to try it out on a big climb for safety reasons, but pushing yourself really hard somewhere fairly safe (a run in or near town with mobile signal?) you are probably ok? Though you probably want to make sure you re-fuel afterwards. Pushing really hard when you're tired is definitely a good idea as long as you don't hurt yourself. When I was bike racing training was always a game of pushing until I had nothing left, and then pushing for a little bit longer. For me it was mostly mental, realising I could always go a little bit further.

I'd really like to hear a qualified opinion on this though!

Also, how do you go on a surprise 18 mile run? If I could work that out I might actually go running more often!

In reply to Mr Fuller:

"I basically forgot to eat"

No, can't say I've ever had that problem. Those who know me probably say it shows.

Neil

In reply to Mr Fuller:

Bonking out is when your body switches from burning sugar ( primarily ) to burning fat ( primarily ). It's not that simple and is not an on/off switch but for this discussion it's good enough.

Whilst switching from one to the other you feel like your legs go to jelly, dizzy, faint etc etc. This is the wall in marathons as well. Normally around 20miles for most people i believe.

If you do it often your body will get more efficient at switching from one to the other.That's how ultra athletes get through it - and by remembering to eat and replace energy in the first place.

I doubt you will burn up your body's ( easily available ) supply of glycogen bouldering but a Winter day out would a big day of aerobic exercise like circuits etc.

If you've a reason to do it i.e. an ultra race coming up then keep practising but if not you'd be better remembering to refuel while you go.

In reply to CrimpShrimp: Haha, not quite. No, I had a fairly standard-sized lunch of pasta/black pudding/veg at the bouldering wall and then ran to join my friend, who had told me were off for a run, but I had no idea how far. On the way round I had two bits of dairy milk and 4 fruit pastels, kindly donated by said friend!

In reply to Neil Williams: It's not a problem I usually suffer with either... It was just I was at a cramped belay and couldn't be arsed to get food out of my bag. Not a mistake I'll make again.

In reply to Bob_the_Builder and biscuit:

Cheers, that pretty much confirms what I thought - not necessarily the best idea unless you need this sort of training. I'm training both for mountaineering and a triathlon at the moment, but neither require the sort of abuse I gave my body recently (definitely not the routes I do, anyway!) so perhaps I should just plan my meals better...

In reply to Mr Fuller:

When I did a lot of winter climbing we used to start the winter taking lots of food onto the hill with us and eating most of it. Invaraibly, as the winter progressed, we found ourselves eating less and less even though the amount of energy expended per day remained much the same. We never hit any walls, not a good idea in winter.

That suggests to me that your body will increase the amount of energy it stores if you excercise it appropriately, even if you don't run out of energy during your "training" sessions.

In reply to Bob_the_Builder: Actually Your body will be burning muscle long before you run out of fat, and particularly post exercise if you don't get some food in you. When you get to the point of going bonk your body really will be burning muscle a lot more than you want it to be if you do any strength based activity.

In reply to Removed User: Yeah, I'd agree with that. If I'm out on a long hike I tend to eat/need a lot less over the course of a day than some of my less-experienced mates (obviously a lot of factors at play there though).

Burning muscle doesn't sound ideal, but then if I'm going to split my time between high power stuff like bouldering, and endurance exercise then obviously the body is going to have to compromise somewhere.

I had a funny one last Monday. I'd done a few hill reps on the bike at lunch and then went track training in the evening. Jogging down to track over the hill I felt light headed and a bit jelly-legged. Thought about turning back but stubborn-ness kept me going.

On the fartlek sessions I was off the back, walking some of the jogs and basically getting caned by people I should be in front of. It wasn't motivation - I just couldn't go any faster. 20 mins later I was going really well on the hill reps and third in our group. Just in front of a fast Bob Graham Rounder. Funny old world.

In reply to Mr Fuller:

I noticed that for me it's important to eat the day before. As don't really have appetite during or after exercise. For that reason I stopped taking any food with me when out climbing. But everyone's different, I know some people need to eat constantly to "refuel", stuffing themselves on every belay.

In reply to Kirill:
But everyone's different, I know some people need to eat constantly to "refuel", stuffing themselves on every belay.

Yup, that's me! ;}

In reply to Kirill: I was going to say the same; I can go for miles on an empty stomach but only if ive had a decent carby meal the day before. I dont eat breakfast until ive been up for at least an hour usually which means i ride an hour into work with no food but feel absolutely fine.
Even on long rides I barely eat; I have no appetite at all when exercising.

In reply to Removed User:

Funny you should say this, I was thinking it the other day but thought I must be imagining it. Last year I used to shovel down food and water constantly during a winter hill day, now I can make it through 6 hours or so on a banana, a couple of cereal bars and under a litre to drink. Just don't feel the need to take in any more, although part of me suspects I would move that little bit quicker if I made the effort.

In reply to Mr Fuller:

i think cover both bases: train 'depletion', and carry snacks in pockets, not your pack.

some good info above re the glyco/fat conversion.

In reply to Bob_the_Builder: Your body turns to burning muscle no matter if you are a low or high level of fat. If you don't consume enough calories or have a high enough glucagon store in muscles (from carbs) then your muscles will be greatly affected. Fat will be burned as well as using up the glucagon store with certain types of exercise but generally going for long sessions or runs on empty will almost certainly depleat muscle. It's also crucial to re fuel as you say after, within an hour buy eating a high carb snack/drink (SOREEEEEEEN!!! ) and if your doing 2 bits of work like climbing then a run to have something high energy/carb but also easily digestable like the energy gels or a banana etc in between.
Recently I have had to increase calorie and carb intake as due to not consuming enough cals/carbs (and doing a huge amount of exercise) I was actually gaining fat and losing muscle.....crazy right.
Oh by the way....I'm in no way qualified but very into sports nutrition.