Dan Plews (strong LCHF proponent, Plews and Prof) just put up the Ironman Kona AG record at 8:24, pretty impressive. Not entirely sure what his in-race nutrition looks like, but certainly trains in an LCHF manner. I know it’s more steady-state than explosive, but still a pretty impressive raw power output on that style of nutrition.
Train low, race high.
With cannabis set to become “legal” in Canada, that advice has a very different context for your neighbours to the North.
From the Prof:
All we can say really is that if you want to optimize your diet in relation to exercise performance, you need to figure out what works for you. LCHF is clearly working for some at the pointy end, but not for others.
@Captain_Doughnutman Yep, they have definitely been pretty open about it not working for all athletes, but Plews & Prof do seem to advocate for it being the primary option, and only checking away to something else once LCHF (with higher carb during racing) doesn’t work.
From personal experience, LCHF definitely worked for me in both general life as well as general fitness endeavours – up to a point. Even though all my KOMs (<60 sec short burst/sprint) were done LCHF and should have relied on carb power, once I started training seriously, LCHF didn’t serve me well for Z4 Z5 efforts; long 4-5hr rides were the same. A much higher carb intake during training and racing made me feel and perform much better (I still try and limit carbs on my off days though). I guess you could say what works for me is a mix of the two…I’m now getting 5-10min KOMs if that’s any indicator of carb power(?).
From personal experience, LCHF definitely worked for me in both general life as well as general fitness endeavours – up to a point.
That was my experience as well, I gave LCHF a ~4 month try about 2 years ago, I was great on the long endurance stuff (although my HR did pop about 10 bpm higher on this diet) and the very short sprint stuff was fine, but for any sustained efforts my legs were trashed. At least for me, carbs = sustained performance.
Captain_Doughnutman basically describes strategic fueling. LCHF has its limits which are found in the higher intensity ranges. Once the glycogen is gone, well, it is gone. Our muscles, for the most part, can store up to 1,200 calories of glycogen as compared to 40,000 calories of fat. The rate of burn on the glycogen is effected by the IF and our efficiency. From my experience, I can push my glycogen stores out to the 4-5 hour range, but this is at a pretty low intensity (think small fire versus big fire). If I add a carbohydrate based fuel source (think sugar and poring my fuel on the fire), I can increase my intensity a fair amount. Overall, we are built for endurance. As we know, the glycogen is there for the high intensity efforts. In my mind, strategic fueling makes complete sense. I believe Chris Froom does a version of strategic fueling. When events are in the ultra endurance range, I believe LCHF is the way to go, but the transition period is rather lengthy. It takes most most of us a good 18-24 months to fully transition our bodies over to efficiently utilizing fat as a fuel source. In the end, we know as endurance athletes we need to figure out what works best for us. I am interested to see what Dan Plews used for nutrition during his race. This is a fascinating topic with more and more research becoming available.
`When events are in the ultra endurance range, I believe LCHF is the way to go, but the transition period is rather lengthy. It takes most most of us a good 18-24 months to fully transition our bodies over to efficiently utilizing fat as a fuel source. In the end, we know as endurance athletes we need to figure out what works best for us.
@gordon50 My understanding is that this adaptation is generally encouraged with a “big bang” of no/low carb to force the use of fat as fuel, and then to slowly reincorporate carbs to regain that high end. I wonder if you could do it more deliberately using increased frequency / duration fasted rides and maintain that top end while increasing metabolic efficiency…