LCHF - Low Carb High Fat Diet Ver 2

[jcza]

tombeej it was not a decision taken lightly. I don't eat processed food as a rule but bonking properly a couple of times caused me to search for the answer. Training is on water only and without breakfast, however racing is a different story because of the demands of very high HR. Consumption is roughly 40gr of carbs (1 x bottle & 1 x GU) per hour when racing but I find I can get away with less at times.

 

I'm very interested to see what the consumption ratio between fat/carb/protein is at very high HR. I don't think I can race carb free without fully depleting glycogen stores.

[Grondpad]

tombeej it was not a decision taken lightly. I don't eat processed food as a rule but bonking properly a couple of times caused me to search for the answer. Training is on water only and without breakfast, however racing is a different story because of the demands of very high HR. Consumption is roughly 40gr of carbs (1 x bottle & 1 x GU) per hour when racing but I find I can get away with less at times.

 

I'm very interested to see what the consumption ratio between fat/carb/protein is at very high HR. I don't think I can race carb free without fully depleting glycogen stores.

 

jcza – just a quick question. Do you use carbs before the race? Like I said a page or two back, I also use carbs on long rides and during races, but I usually only start consumption about 30min in and for me it works a charm. I think my “reserves” can manage for longer but I don’t want to bonk (again).

[McD23]

My two cents,

Have been LCHF committed for 9 months, log on average 30 hours months, but all done with watts in structured sessions. So very little riding and mostly training, there is a massive difference in intensity between the two I find.

Initially I had a good response and felt no real difference in my ability and output, taking no carbs and significantly less water on rides up to 3 hours ( don't really do much training longer than this currently ).

Then after couple of months found that on higher intensity rides over 2h20 the wheels literally came off, obviously a problem when doing mtb races.

I persisted for a awhile thinking it was a process of adaption, but have come to realise the simple fact, if you are going to exercise at 85% plus of heart rate for more than 2 hours, fat oxidisation is not going to be able to provide you with sufficient fuel quickly enough to prevent you from depleting your onbody fuel faster than you can replace it.

I now take a 50% diluted 32gi fluid mix and a energy bar that has the highest fat and protein content I can find.

I start consuming before the intensity has been sustained for long, as if I wait I find it is too late to try and recover the deficit created in glycogen stores.

I did a 3 stage race this weekend.

 

58km 2h27 avg hr 157

65km 2h45 avg hr 153

57km 2h45 avg hr 153

My max heartrate on bike 178 ( 41 years old )

Each day I had 1 750ml bottle of diluted 32gi and one hammer recover bar on the ride, this kept me strong until finish.

 

I have noticed that the rpe for me is different now than how I remember it, my legs feel tired and as if lactic acid is building up way sooner that when I was carb fuelled, but this is a mind game, as if committed I can push and hold this feeling despite not enjoying it and achieve as good a number in watts as when carb fuelled.

I have for some time done 2 x 20min intervals on Kloof in CT for my threshold power.

When carb fuelled my recent avg 299 watts ( weigh 69kg ) and drop 4/5% on second one, I seem to recall it a case of the heart and lungs feeling like they where the restrictive part of my performance and less the legs.

I recently did the 2x20min fully fat adapted, it dint feel good and legs felt like they struggling from early on in the interval.

The big surprise for me was a pb this year of 306 and 305 watts for the two intervals ( still 69kg ) . Had I not had the numbers to compare there is now way I would have ventured them to be my two best intervals this year.

It taught me that I need to get used to a different feeling when in the 'hurtlocker' than I have been used to.

This brings me upto my last observation, I have been carb fuelled teaching my body how to react under stress in exercise foe over 20 years, now that I am fat adapted for 9 months how realistic and reasonable is it to expect my body to come anywhere near the efficiencies and feelings I know with the latter system ?

I do wonder what would be achievable under multiple years of sustained high intensity training as a fat adapted athlete, in my mind I am sure the body will continue to improve the 'system' as it comes to realise it is adapt or die time ..

 

a side note, prior to really embracing LCHF I was weighing in consistently at 73kg , subsequently I am now at 69kg, if one looks at my watts/kg , then actually despite struggling with intensity I have had a solid improvement on that figure.

Edited September 17, 2013 by McD23

[Roux 1]

Another question:: do you increase protein according to distance/intensity done for day or to a race.

 

Example:: use rule of thumb 1,2g/lean kg mass and if very active up to 1,5. But that is not enough if intensity was high or long duration. It might increase to 2g/lean kg mass.

[jcza]

jcza – just a quick question. Do you use carbs before the race? Like I said a page or two back, I also use carbs on long rides and during races, but I usually only start consumption about 30min in and for me it works a charm. I think my “reserves” can manage for longer but I don’t want to bonk (again).

 

It depends how I feel when I wake up, first choice is bacon & eggs but now and again I'll have a muffin or cookie. During the race I drink when thirsty and will take the GU when cals expended are between 600 - 1000, again depending on how I feel. At times I don't feel I need the GU but as you say, don't want to bonk cause then its too late.

[tombeej]

Jcza, I didn't mean to say it's wrong to have GUs; I'm sure they are excellent products. Just a personal choice thing. I'm actually with you in terms of the need for quick release carbs during high intensity exercise. In fact, those with a long memory will remember that at one stage I was almost alone in my defence of the humble carb on the old thread, and my experience that my performance on the bike only started really improving when I started bringing more (top quality) carbs back into my diet. A similar journey that HMT has just been on.

 

So just to reiterate, I'm with you all on the need for high GI during intense exercise. But just cautioning on WHEN to take them.

 

And re. GU, I try eat similar, but are high GI dried fruits, etc. This means I might have to start eating them slightly sooner than you'd start on the GUs coz their rate of absorption is a little slower .

[jcza]

Jcza, I didn't mean to say it's wrong to have GUs; I'm sure they are excellent products. Just a personal choice thing. I'm actually with you in terms of the need for quick release carbs during high intensity exercise. In fact, those with a long memory will remember that at one stage I was almost alone in my defence of the humble carb on the old thread, and my experience that my performance on the bike only started really improving when I started bringing more (top quality) carbs back into my diet. A similar journey that HMT has just been on.

 

So just to reiterate, I'm with you all on the need for high GI during intense exercise. But just cautioning on WHEN to take them.

 

And re. GU, I try eat similar, but are high GI dried fruits, etc. This means I might have to start eating them slightly sooner than you'd start on the GUs coz their rate of absorption is a little slower .

 

I remember when we did the comparison between bananas and GUs etc. This thread is a great journey of discovery for me. I also add butternut & other veg to pre-race dinner for carbs. Generally I don't take the high GI stuff pre-race but during race.

 

I agree with McD23 regarding the fuel at high HR. Protein is not really a source of fuel and the body does not necessarily have enough left to convert fat to fuel, which leaves carbs.

[Riaanvt]

A graphical representation of what normal blood glucose and insulin concentrations looks like over time after a meal:

 

http://www.phlaunt.com/diabetes/pics/164224951NormalBGGraphs.jpg

[davetapson]

Re. the carb fuel thing.

 

Jeroen Swart tweeted a link to a study a while ago that discovered that you got as much 'response' to carbs by just swishing them around your mouth and then spitting them out than you did by swallowing them.

 

I will try this sometime by taking energelly jelly babies and just noodle one around in my mouth rather than chowing them down and see if this is right.

 

I suspect there may be truth in this. When I was doing my death march Sabie earlier on this year, I took genucan with me. When I started dying on top of the climb, I chowed down some ucan and immediately felt better. I was sure that the glucose could not have been absorbed as quickly as the time taken to feel better. Particularly with a slow release carb product.

 

If this is the case, it might be one of those central governor things CG says you are short of BG - you feel k@k. CG tastes sweet stuff in your mouth and says 'Cool, ok, GO!!' Something like that.

 

 

Re. the 'you can't maintain intensive exercise on fat only' - if so, how did Oscar Chalupsky win the Kona surf ski challenge on water only?

 

One observation I have (and I'm not having a go, just observing) is that folk battle through the adaption phase and in desperation re-introduce carbs. The observation is then 'when I re-introduced carbs I was fine'.

 

My experience was that it took > 4 months to adapt. I rode first day of Sani on water only (rode, not raced) and it was a bit touch and go which would indicate that I was only just getting adapted. This was after probably 2 months of Paleo and 4 months of LCHF. Im not sure that trying to race on 3 - 4 months adaption is feasible, and I'm not sure that failing to be able to race on water after 3 - 4 months adaption is a true indicator of 'you can't race on water'... <- add Joe Friel defensive tone here!!

 

I'll carry on with the LCHF thing (because not doing it causes me more discomfort than doing it) and will see how I do at next year's sani. If I can do it on water, I will come back and update this post!!

 

PS: I took some carbs for Sani day two because I didn't want the risk of dying half way, but I have to admit, when I got to the end, my feeling was that I'm not sure the carbs made as much of a difference as I was expecting.

[McD23]

Jeroen Swart tweeted a link to a study a while ago that discovered that you got as much 'response' to carbs by just swishing them around your mouth and then spitting them out than you did by swallowing them.

 

I often swill my liquid around in my mouth for long as possible before swallowing, it definitely leaves me feeling like I have had more than a little sip.

I also take a bite of bar and then store it in side of mouth like a hamster letting it slowly dissolve instead of wolfing down mouthfuls.

[jcza]

One thing that is always mentioned when discussing LCHF and specifically training to become a fat burner is that training should be at low HR. Some say below 75% of VO2Max other say even lower.

[htone]

Love where this discussion is heading. Most of us have been doing LCHF for less than a year. MY guess is that in a year or two from now we may discover astounding things about our bodies' ability to burn fat a lot quicker than we do now - I agree on the Oscar Calupsky (and Bruce Fordyce) story - they have trained to do extreme events only on bodyfat and water, there must be some learning in that for us.

 

I don't dispute for a second that we run out of glycogen quickly (now) at levels well into our VO2Max zone, but I suspect with enough time and by systematically training at lower and lower levels of carb intake we will be able to perform at levels we can only speculate about now. At least I hope we will.

 

My real battle right now is with my weight that is just absolutely not moving, from next week I am going to severely restrict my milk intake to see if that makes any difference at all.....

[Sniffie]

Descent.

 

Had to look at the site to see which one is was and I see it's 11, 12, 13 th Oct. Damn, but I've cut this one fine!!

Will be seeing you then!

[Roux 1]

One thing that is always mentioned when discussing LCHF and specifically training to become a fat burner is that training should be at low HR. Some say below 75% of VO2Max other say even lower.

 

Fat Burner or Ketone "burner" i.e. using ketones for energy

[davetapson]

Will be seeing you then!

Lekker man! Will contact you closer to the time to get meetup details...

[davetapson]

Love where this discussion is heading. Most of us have been doing LCHF for less than a year. MY guess is that in a year or two from now we may discover astounding things about our bodies' ability to burn fat a lot quicker than we do now - I agree on the Oscar Calupsky (and Bruce Fordyce) story - they have trained to do extreme events only on bodyfat and water, there must be some learning in that for us.

 

I don't dispute for a second that we run out of glycogen quickly (now) at levels well into our VO2Max zone, but I suspect with enough time and by systematically training at lower and lower levels of carb intake we will be able to perform at levels we can only speculate about now. At least I hope we will.

 

My real battle right now is with my weight that is just absolutely not moving, from next week I am going to severely restrict my milk intake to see if that makes any difference at all.....

 

My view on this is that the liver can (should be able to?) produce sufficient glucose to fuel the body during competition, but that conditions need to be set up to enable the liver to do this. Why do I think this? Because I read it somewhere - probably on this thread! How to do that? I suppose train and race on water.

 

I imagine that it might get ugly during the adaption phase, but I don't really see how else to do it? If you race on carbs, the biochem pathways required for the liver to produce sufficient glucose at high intensity will never need to be set up.

 

Well, that's my theory, anyway.

Edited September 17, 2013 by davetapson