Whats the best value for money race drink to have in your pack ?

[jcza]

What a cool thing to have The Doctor supply this forum with his insights.

[emoji1476]

Agree and I like the research published on the Cadence site.

[Patchelicious]

The carb / fat question is a very interesting one for which we don't have enough answers yet.

 

We are doing quite a bit of research in this domain at the moment and recently published a paper on this. Link here:

 

https://www.ncbi.nlm.nih.gov/pubmed/26918583

 

Here is what we know at the moment:

 

During exercise the primary fuel source is carbohydrate. Peak carbohydrate oxidation rates are as high as 8g/min at very high intensities in elite athletes.

 

We used to think that peak fat oxidation rates were always below 1g/min as nobody had ever reported higher than this in any study. Most elite athletes have peak fat oxidation rates of about 0.6g/min

 

When people started banting and also exercising new data emerged that showed that on a LCHF diet, peak fat oxidation rates could reach as high 1.8g/min in a small number of athletes. That is more than twice what we previously thought was possible.

 

This is still quite a few orders of magnitude lower than CHO oxidation rates though.

 

However, that changes our paradigm to some extent with respect to fuelling for endurance sports.

 

A fat oxidation rate of >1.5g/min can sustain an intensity equivalent to approximately 65% of VO2max power. Which is a fairly easonable pace.

 

It is therefore possible to fuel without any carbs for an ultra-endurance event when the pace is not excessively high and is kept constant. A good example would be an age grouper or competitive Ironman athlete on a relatively flat course profile.

 

Things get a little more complicated when you start looking at sports in which the pace varies significantly e.g. road or MTB

 

Habitual LCHF athletes have down regulated CHO absorption rates and also have lower oxidative and glycolytic capacity for CHO. As such, the carbs that they do have stored are not as accessible as they would be in a mixed diet athlete. In addition, they cannot absorb CHO at the same rate as a mixed diet athlete.

 

The study posted above showed that they also do not convert fats or proteins into glucose (gluconeogenesis) at a faster rate than mixed diet athletes. So they are somewhat dependent on fat as a source of energy (or so it seems from our data to date).

 

The upside is that fat is a virtually limitless energy supply and you will therefore never bonk as a LCHF athlete. Many LCHF athletes are completing events like the Ironman on fluids alone. No exogenous fuel!

 

Whether the LCHF diet is a good diet for overall health in the long term is still unclear. So the above points relate solely to performance.

 

The downside is that LCHF can result in greater fatigue in the first few months and may also suppress the immune response. We have unpublished data from ironman athletes that demonstrates higher rates of infections for LCHF athletes than their traditional counterparts. Monitoring fatigue is therefore very important when following a LCHF diet. Adaptation to LCHF as an athlete also takes a few months. It's not something you can switch to overnight.

 

A new strategy that has emerged in recent years is one which attempts to gain some benefit from both fats and CHO. This is know as periodised nutrition.

 

It involves 2-3 fasted exercise sessions each week to stimulate fat oxidation rates. The other 2-3 sessions are down with maximal CHO feeding rates (60-90g/hr) to stimulate the up-regulation of CHO transporters in the gut (training the gut) and to maintain CHO oxidation capacity and glycolysis in the muscle. It also results in a leaner athlete.

 

In races (particularly ultra-distance) the athlete will sometimes fuel with a mix of carbs and fats in the first few hours and then switch to CHO in the last 2 hours. Typical is a Tour De France mountain stage in which the first few climbs are ridden at a lower intensity and then the attacks start to happen on the last climb.

 

With this strategy we can get athletes to achieve fat oxidation rates that are higher than traditional mixed diet athletes but they are still below 1g/min. However, it creates a larger fuel tank while maintaining the ability to perform very high intensity exercise.

 

We are busy writing up data on a LCHF ultra athlete that was tested in LCHF state and again in when using periodised nutrition. The periodised nutrition improved 20km TT power but did not improve 100km TT. So this does confirm our hypothesis to some extent. We will be publishing this data soon.

 

I hope that gives some clarification. We still need to do answer a lot of questions but the science is definitely being conducted and will be published in the coming years.

Thanks Doc, as always.... more data is needed ????

 

Can we say that with current reasearch, that for 3 hour races at high intensity ( the median for most SA road races ) that some good quality carb drinks are indeed needed?

 

I for one often ride 4-5hours with no breakfast and only on water, but if if the intensity picks up to IF 0.8 plus for more than 2 hours, that I need to supplement my intake with carbs.

[Patchelicious]

Agree and I like the research published on the Cadence site.

The one thing that I have always liked about Dr J is that he engages as a true researcher, and supplements his statement with caveats. Many others will simply state something as an absolute.

[V12man]

Jeroen - I am curious as to the latest positions regarding ketones as race fuel- so far I have only seen speculation rather more than hard science.

[The Doctor]

Thanks Doc, as always.... more data is needed

 

Can we say that with current reasearch, that for 3 hour races at high intensity ( the median for most SA road races ) that some good quality carb drinks are indeed needed?

 

I for one often ride 4-5hours with no breakfast and only on water, but if if the intensity picks up to IF 0.8 plus for more than 2 hours, that I need to supplement my intake with carbs.

 

That is a fair interpretation.

 

Just note that you could also do 3 hours of hard riding with a LCHF strategy. 

 

However then it would ideally need to be a constant intensity.

[The Doctor]

The one thing that I have always liked about Dr J is that he engages as a true researcher, and supplements his statement with caveats. Many others will simply state something as an absolute.

Thanks. I appreciate the acknowledgment.

 

As a scientist it is always important to remember that there are absolutely NO scientific facts.

 

There is only scientific consensus. Consensus often changes based on the existing evidence.

 

New evidence -> New consensus.

 

So I keep an open mind and let the data tell us what we currently know to be best practice.

[The Doctor]

Jeroen - I am curious as to the latest positions regarding ketones as race fuel- so far I have only seen speculation rather more than hard science.

 

Current evidence for exogenous ketones as a fuel source is not at all convincing. 

[shaper]

The carb / fat question is a very interesting one for which we don't have enough answers yet.

 

We are doing quite a bit of research in this domain at the moment and recently published a paper on this. Link here:

 

https://www.ncbi.nlm.nih.gov/pubmed/26918583

 

Here is what we know at the moment:

 

During exercise the primary fuel source is carbohydrate. Peak carbohydrate oxidation rates are as high as 8g/min at very high intensities in elite athletes.

 

We used to think that peak fat oxidation rates were always below 1g/min as nobody had ever reported higher than this in any study. Most elite athletes have peak fat oxidation rates of about 0.6g/min

 

When people started banting and also exercising new data emerged that showed that on a LCHF diet, peak fat oxidation rates could reach as high 1.8g/min in a small number of athletes. That is more than twice what we previously thought was possible.

 

This is still quite a few orders of magnitude lower than CHO oxidation rates though.

 

However, that changes our paradigm to some extent with respect to fuelling for endurance sports.

 

A fat oxidation rate of >1.5g/min can sustain an intensity equivalent to approximately 65% of VO2max power. Which is a fairly easonable pace.

 

It is therefore possible to fuel without any carbs for an ultra-endurance event when the pace is not excessively high and is kept constant. A good example would be an age grouper or competitive Ironman athlete on a relatively flat course profile.

 

Things get a little more complicated when you start looking at sports in which the pace varies significantly e.g. road or MTB

 

Habitual LCHF athletes have down regulated CHO absorption rates and also have lower oxidative and glycolytic capacity for CHO. As such, the carbs that they do have stored are not as accessible as they would be in a mixed diet athlete. In addition, they cannot absorb CHO at the same rate as a mixed diet athlete.

 

The study posted above showed that they also do not convert fats or proteins into glucose (gluconeogenesis) at a faster rate than mixed diet athletes. So they are somewhat dependent on fat as a source of energy (or so it seems from our data to date).

 

The upside is that fat is a virtually limitless energy supply and you will therefore never bonk as a LCHF athlete. Many LCHF athletes are completing events like the Ironman on fluids alone. No exogenous fuel!

 

Whether the LCHF diet is a good diet for overall health in the long term is still unclear. So the above points relate solely to performance.

 

The downside is that LCHF can result in greater fatigue in the first few months and may also suppress the immune response. We have unpublished data from ironman athletes that demonstrates higher rates of infections for LCHF athletes than their traditional counterparts. Monitoring fatigue is therefore very important when following a LCHF diet. Adaptation to LCHF as an athlete also takes a few months. It's not something you can switch to overnight.

 

A new strategy that has emerged in recent years is one which attempts to gain some benefit from both fats and CHO. This is know as periodised nutrition.

 

It involves 2-3 fasted exercise sessions each week to stimulate fat oxidation rates. The other 2-3 sessions are down with maximal CHO feeding rates (60-90g/hr) to stimulate the up-regulation of CHO transporters in the gut (training the gut) and to maintain CHO oxidation capacity and glycolysis in the muscle. It also results in a leaner athlete.

 

In races (particularly ultra-distance) the athlete will sometimes fuel with a mix of carbs and fats in the first few hours and then switch to CHO in the last 2 hours. Typical is a Tour De France mountain stage in which the first few climbs are ridden at a lower intensity and then the attacks start to happen on the last climb.

 

With this strategy we can get athletes to achieve fat oxidation rates that are higher than traditional mixed diet athletes but they are still below 1g/min. However, it creates a larger fuel tank while maintaining the ability to perform very high intensity exercise.

 

We are busy writing up data on a LCHF ultra athlete that was tested in LCHF state and again in when using periodised nutrition. The periodised nutrition improved 20km TT power but did not improve 100km TT. So this does confirm our hypothesis to some extent. We will be publishing this data soon.

 

I hope that gives some clarification. We still need to do answer a lot of questions but the science is definitely being conducted and will be published in the coming years.

Thanks for the write up, having recently been diagnosed pre diabetic, who has gone on to a low carb high protien diet, am reading, experimenting with periodic carb intake for high intensity and much reduced carbs during my endurance events and more protein intake. Will be interested when you publish your research.

[IH8MUD]

According to Carte Blanche last night, a veterinarian, and some input  from Prof Tim.

 

We should eat only  one meal a day, at night. 

 

So on your bicycle you should be fine with just water and perhaps an Eisbein in your bottle cage for long rides. 

 

 

 

 

PS . . I have been to Jeroen's talks and his approach and advice have worked best for me over the years and makes sense.  

[Duane_Bosch]

For what it's worth.

 

For short rides. <50km. Just water and a post ride coffee

Anything over 50km. 1 bottle water. 1 bottle Game with a bit of salt and a date every 7-10km.

 

I try to use the Game & Water together but I like to have a little Game to finish. The effect is probably all in my head tho.

 

Living in HB All my rides tend to start with a climb and finish with a climb. I find Suikerbossie on cold legs particularly tough.

[jcza]

Cadence CarboFuel on special at CWC for R149

 

PS: I'm not employed by CWC in case you're wondering. 

[V12man]

Cadence CarboFuel on special at CWC for R149

 

PS: I'm not employed by CWC in case you're wondering. 

Are you ordering? add 2 in for me... Please...

[jcza]

Are you ordering? add 2 in for me... Please...

 

Will check when I get home but I still have 2 x tubs from Dec special I think

[V12man]

Will check when I get home but I still have 2 x tubs from Dec special I think

Dankie Troep...

 

Seems like you need to go racing a bit...

['Dale]

Cadence CarboFuel on special at CWC for R149

 

PS: I'm not employed by CWC in case you're wondering.

But are you not a Cadence Brand Ambassador then maybe ????

 

 

????

[jcza]

But are you not a Cadence Brand Ambassador then maybe

 

 

 

 

Hope the sponsor sends new kit before world champs in March