Dietitian's corner

[Patchelicious]

Google Ancel Keys and the 7 Country Study.

[Barend de Arend]

You will probably find that is because when most GPs were in medical school, many of the studies they were taught on we're based on incorrect and sometimes even falsified information from the 50s, 60s and 70s

 

That's still the state today.  Nutrition science today is often incorrect, deliberately broken, junk science.  For example, you can find research that says eating chocolate will make you skinny.

 

Nutrition science is very, very difficult to get right, because it's difficult to get an accurate control group over the long term.

[Barend de Arend]

See the below article, interesting reading, seems to be supported by research and aimed at cyclists.

 

 

http://cyclingtips.com.au/2015/06/why-you-should-think-twice-before-trying-a-low-carb-high-fat-diet/

 

Good article.

 

And that's why there's a difference between the ideal diet for someone trying to finish a 100km race in the middle of the open pack, and someone trying to race a 200 km race for first place.

 

Both are "cyclists."  You have to know your goals, and then find out what eating strategy will support that goal.

 

If you go to the gym once a week, don't eat like a body builder.

[Sports Certified Dietitian]

Good article.

 

And that's why there's a difference between the ideal diet for someone trying to finish a 100km race in the middle of the open pack, and someone trying to race a 200 km race for first place.

 

Both are "cyclists."  You have to know your goals, and then find out what eating strategy will support that goal.

 

If you go to the gym once a week, don't eat like a body builder.

Really good article.

[Sports Certified Dietitian]

That's still the state today.  Nutrition science today is often incorrect, deliberately broken, junk science.  For example, you can find research that says eating chocolate will make you skinny.

 

Nutrition science is very, very difficult to get right, because it's difficult to get an accurate control group over the long term.

I think it depends where one looks for scientific evidence on nutritional science. One has to be critical about how data is obtained and what conclusions can be drawn from it. I'm not aware of doctors being taught intensively in a formal setting on nutrition, hence the need for dietitians in hospital settings. 

[Barend de Arend]

I think it depends where one looks for scientific evidence on nutritional science.

 

Yes, it does, just like it did in the 50s, 60s and 70s.  And so does peer review.  And disclosing any sponsors.  And fully disclosing your method.

 

And you have to know this when you read this month's magazine -- or bestseller -- and try to out-think your doctor.

[Sports Certified Dietitian]

Seems everyone wants to state a claim about what is the best. IMO the body is an amazing adaptive organism.......if you feed it carbs for sport performance it will adapt to utilise carbs. If you feed it fat, it will adapt to utilise fat. Almost the same as the body adapts to different kinds of training.

 

But even more important, dietary guidelines for health (normal population) does not completely fit the dietary requirements for sport performance. Regarding the discussions on energy sources in the body.......have seen how elite ultra-endurance athletes (ie Comrades) at 95% of maximum intensity (performance) still have a respiratory exchange rate (RER) below 1 and simultaneous blood lactate concentration below the "magicall" 4mmol/L. With a profile of physiological parameters like this indicating energy system and substrates utilsed, it would be interesting to read other opinions and ideas on this.

 

Seems there might be a bit of a gap between theory and rea life............especially when it comes to high intensity activity over prolonged periods.

One would expect these elite athletes to have an RER above 1 at those intensities, indicating predominantly carb fueling. It wouldn't surprise me to hear there is still mixed substrate utilisation (see graph at 65% VO2 max) even at these high intensities. If I'm not mistaken there is far greater lactate clearance in athletes as the level of fitness rises. Perhaps this accounts for the lowish level despite the intensity?

[Sports Certified Dietitian]

I think the reason why the science behind LCHF has yet to be accepted by the majority is because it had been labeled a "diet" and the perception of another "fad".... Tis a pity. Being anti Noakes is the "new cool" kind of like it was cool 2 years ago to bant. Hype cycle stuff again....

 

Have a read on the cardiac benefits of LCHF.

 

I myself was born with a heart condition which was treated by operation a few years back. When I started training really hard (12 hours plus a week) some symptoms started to retun. But since I increased my fat intake I have felt a remarkable difference in its negative effects on me. I unfortunately do not have data to support that it's purely LCHF as my overall fitness has improved too.

There have been some good studies by Louise Burke if I am not mistaken showing mixed to no benefit with LCHF diets. Inbox me your email and I can hopefully find and send you an article or two if you keen to read them. Just to clarify - I'm referring specifically to sport performance and not different areas of health.

[Sports Certified Dietitian]

There are some challenges but most places you go out and eat there are vegeterian options.

Can I assume that you are a dietician? I would like to be able to discuss my diet with a dietician who understands cycling and a vegeterian diet.

We pretty lucky in this era in that generally there is lots of provision for different ways of eating, such as vegetarianism, gluten-free etc.

 

I am a practicing dietitian, and would be happy to assist you. My original post has my contact details.

[BarHugger]

Publication:

 

"Training with low muscle glycogen reduced training intensity and, in terms of performance, was no more effective than training with high muscle glycogen. However, fat oxidation was increased after training with low muscle glycogen, which may have been due to enhanced metabolic adaptations in skeletal muscle."

 

Training with low muscle glycogen.pdf

 

 

[NotSoBigBen]

I reckon if you find something that works for you then that is great and do it, if you struggling with that then pay some one to help you .....

 

I'm not going to try to convince anyone that 'my way' is right and it will for work anyone else, in fact I know that my wife has tried and it had no effect for her as far as weight loss goes .....

[Patchelicious]

There have been some good studies by Louise Burke if I am not mistaken showing mixed to no benefit with LCHF diets. Inbox me your email and I can hopefully find and send you an article or two if you keen to read them. Just to clarify - I'm referring specifically to sport performance and not different areas of health.

Thanks, I have most of them.

 

Like I said, I agree that for high performance events and sustained training above 70% VO2Max that you need to compliment your LCHF diet with additional slow release carbs.

 

So for my midweek intervals (anything shorter than 2 hours body stores are enough) and weekend LSDs I dont take extra carbs at all, water and biltong with some nuts. For races and race simulation type rides, I do, usually in the form of a carb dinner the night before and carby breakfast then gels during the race as well as a carb based drink.

 

I think the fact that most of us are not "high performance" athletes doing sustained high intensity sessions and regular races means we can reap the other benefits of LCHF. As said my main motivation is it helps knock the weight off ( my current biggest challenge when it comes to Power to Weight is weight, well its the easiest gain) so there are very real performance benefits for me. The health benefits of LC are indisputable.

 

As a diet (as in what I eat everyday, not a "fad") I think its great, and I will continue on it. As a race fuel at intensity it does not suffice for me, hence me introduction some extra carbs. But I am not going to drop LCFH and eat according a standard western diet again, just because I need some extra carbs 6-8 times a year

[cadenceblur]

That's my philosophy as well. I'm just conflicted around my post exercise nutrition. What does one replenish with?

[Sports Certified Dietitian]

Thanks, I have most of them.

 

Like I said, I agree that for high performance events and sustained training above 70% VO2Max that you need to compliment your LCHF diet with additional slow release carbs.

 

So for my midweek intervals (anything shorter than 2 hours body stores are enough) and weekend LSDs I dont take extra carbs at all, water and biltong with some nuts. For races and race simulation type rides, I do, usually in the form of a carb dinner the night before and carby breakfast then gels during the race as well as a carb based drink.

 

I think the fact that most of us are not "high performance" athletes doing sustained high intensity sessions and regular races means we can reap the other benefits of LCHF. As said my main motivation is it helps knock the weight off ( my current biggest challenge when it comes to Power to Weight is weight, well its the easiest gain) so there are very real performance benefits for me. The health benefits of LC are indisputable.

 

As a diet (as in what I eat everyday, not a "fad") I think its great, and I will continue on it. As a race fuel at intensity it does not suffice for me, hence me introduction some extra carbs. But I am not going to drop LCFH and eat according a standard western diet again, just because I need some extra carbs 6-8 times a year

Like what you had to say. Makes good sense. If it works for you and you happy eating like that then I say go for it.

[FlyingScot]

Great topic!

 

I have a question - I have been seeing a sports dietitian for the past few months and have seen big gains in terms of weight loss (specifically body fat). I am 1.82m tall and weigh 78kg. Since seeing the dietitian I have lost 8kg, but most of my muscle mass has remained untouched, the approach being to protect the muscle by taking in enough protein, through the day and especially after training. Realistically I could lose another 2 kg in fat, bringing my weight  down to 76kg. However, I would like to weigh 72kg...for them hills! The only way I see this happening is by losing muscle mass - it is already clean muscle (85%), so I don't see huge gains in cleaning it up more.

 

Would you agree that my best approach is to lose the 2kg fat and then limit my protein intake for the last 4kg? Can I expect a loss in power by doing this?

 

I will get my dietitians opinion tomorrow morning and let you know her thoughts and suggested approach.

[Patchelicious]

Great topic!

 

I have a question - I have been seeing a sports dietitian for the past few months and have seen big gains in terms of weight loss (specifically body fat). I am 1.82m tall and weigh 78kg. Since seeing the dietitian I have lost 8kg, but most of my muscle mass has remained untouched, the approach being to protect the muscle by taking in enough protein, through the day and especially after training. Realistically I could lose another 2 kg in fat, bringing my weight  down to 76kg. However, I would like to weigh 72kg...for them hills! The only way I see this happening is by losing muscle mass - it is already clean muscle (85%), so I don't see huge gains in cleaning it up more.

 

Would you agree that my best approach is to lose the 2kg fat and then limit my protein intake for the last 4kg? Can I expect a loss in power by doing this?

 

I will get my dietitians opinion tomorrow morning and let you know her thoughts and suggested approach.

That is a great question, and one that I am dealing with too.

 

I am also 182cm, and my target weight by end the start of the next racing season is 72kg - 73kg... I am currently 79kg.

 

People are often surprised by how much more they can lose before muscle performance is affected. We carry much more fats than what you can see.

Go check these guys out http://www.dexacpt.com/I am still needing to go.

 

Edit: You can also lose muscles where it doesnt matter. I used to gym a bit and did triathlons... I looked at a Tri photo from 3 years ago, and my arms/shoulders are way smaller. so muscle mass loss doesn't necessarily affect power output.

 

I would venture and say that I think we can go well below 75kg before the W/Kg number starts being negatively affected.

 

Go buy the latest Tour de France magazine, they have all the riders heights and weights, most of the 180cm type height guys are below 70kg. I am sure that if their power loss being that light outweighed the benefits of their weight, they would not be that light.

 

I am by no means comparing you/us to pros but more pointing out that they would only do it if it helped them.