Keto Cyclist, 1 month in - results and failures


(Jason Rodger) #1

Posting for accountability really

So, backstory I am a cyclist who for years has eaten the standard high-carb pasta and rice based diet that we all seem to follow. But I also struggle to take in food while riding, always have; it makes me a bit nauseous. This has been a limiting factor for me.

So the switch to Keto was an experiment to see if I could switch myself to fat burning, this would negate the need to eat while riding to some degree, Also I should disclose that I am considered heavy for a bike-rider, probably 30lbs more than my buddies, but my legs are strong, so I keep up.

I have been trying for 20g carbs a day and usually missing by 3-4 grams, but recording Ketones of between 0.2 and 0.4 on the meter and stick. I have however struggled to get my fat intake above 50% - I suspect years of programming are still pushing me towards the leaner cuts of meat. Most of my fat is coming from full fat yogurt and avocados.

Lots of positives so far - firstly is weight loss, 19 lbs in the first month, so I am now getting towards where the rest of my gang is weight wise, this wasn’t my primary goal but it is welcome. I also now have a lot more energy day to day.

One strange non-scale victory is that My hair, skin and nails seem to be in better condition than they have been in years, this could be down to me supplementing collagen, but the difference seems to large to be down to this alone.

However there are negatives; remember that 19 lbs I lost? its not all been fat, my peak wattage has dropped off by about 5% and the Garmin scales confirm that some muscle has gone - only to be expected I suppose.

In terms of cycling overall, its not been good. For the first two weeks I could barely ride my bike - for the first week I couldn’t even complete a 45 minute Peloton workout that I do every morning as a wake-up. And on the road even a flat 5 mile spin was killing me.

But it is coming back now, my watts are still showing low, but I am back to being able to ride for 2-3 hours, although not quite as fast just yet, I seem to have lost all ability to sprint.

I am going to keep at it, I am not super-concerned about any further weight loss, but I now need to read up on maintaining and indeed growing muscle mass, I would like to get leaner, but not necessarily lighter if that makes sense.


(Allie) #2

Sounds like you’re doing well. It’s very early days, the body takes time to adapt, and bio-impedance scales cannot be relied upon at all (helpful guide for trends, but nowhere near accurate). Your power will come back as you get more adapted and you’ll likely find that going forward, you can tolerate (and may actually need) a higher amount of carbs due to your training of choice.


(Bob M) #3

It’s going to take a while, probably a few months. And if you like podcasts, I recommend Human Performance Outliers with Zach Bitter. He’s an ultramarathoner who uses keto and carbs.


(Bacon is a many-splendoured thing) #4

If you are eating roughly equal amounts by weight of fat and protein, then you are getting 69% fat by calories, so you’ve already achieved your goal.

Fat is not magic on a ketogenic diet, it is merely a source of energy that doesn’t stimulate an insulin response, whereas carbohydrate, our other source of energy, stimulates a massive one.

Not only that, but fat contains over twice as many calories per gram as carbohydrate does (9 for the former, 4 for the latter), so if you cut your carbohydrate intake by 300 grams, it only takes 133 grams of fat to give you the same amount of energy. Eat enough fat to satisfy your hunger, and you’ll be fine.

This is perfectly normal. Don’t overstress your body till it recovers. Right now you are going through a phase we call “fat-adaptation” or “keto-adaptation,” and it will be a few more weeks before your muscles recover. They shut down their fat-metabolising processes because you weren’t using them; now they have to reactivate the processes, and it takes time. Eventually, your endurance will return (it takes six to eight weeks for most people), and you will become bonk-proof. Your explosive power will take a bit longer to return, but it will, as well.


(Bacon is a many-splendoured thing) #5

Forgot to mention The Art and Science of Low-Carbohydrate Performance, by Stephen D. Phinney, M.D., and Jeff S. Volek, Ph.D. Dr. Phinney is a long-time nutrition researcher and cyclist, Prof. Volek is a sport nutritionist and former power lifter.


(Jason Rodger) #6

Thanks for your comments, very helpful, I will order that book. I am reading a couple from Taubes at the moment, but this looks more specific to my needs.


(Bob M) #7

The way I think about it is that there’s a system in your body to replace glycogen (and perform other recuperation tasks). When you switch to low carb, it takes a while to convert that system to using ketones (and, I assume still some glucose). For instance, you will likely see high blood ketone levels.

But after a while, the system – and I guess I should include actual muscle cells here – will transition over. This typically means your requirements for ketones will go down, and potentially you’ll have some higher blood sugar, particularly in the morning.

I’ve noticed, even being keto for a long time, that there are times I cannot recover. I’m only exercising 4 days a week, so most times I’m fine. But if I exercise over the weekend (normal) while also doing a ton of physical work for the house, such as cutting down and moving trees), I can’t recuperate to do my Monday morning body weight training. I’ve had to delay it. If I eat some carbs on Sunday, though, I can perform my Monday training.

While Zach Bitter is on a different level (he’s running more in one week sometimes than I’ll “run” in a month or many months), he finds something similar. He can keep keto when he’s not training for anything, but once he starts ramping up the mileage and number of training sessions, he has to add some carbs.


(Bacon is a many-splendoured thing) #8

I’d just like to add a bit of nuance to this: skeletal muscles actually prefer fatty acids over ketone bodies (and glucose, too), hence the period of adaptation. The mitochondria have typically been damaged by excessive glucose metabolism, and there are other cellular processes, as I understand it, that have been deactivated from lack of use. The mitochondria need time to heal, and these other processes need time to be reactivated. But once that has been accomplished, the muscles are fully readapted to metabolising fatty acids, and they will refuse glucose and ketone bodies in favour of fatty acids (this is called, variously, “phyisological insulin-resistance” or “adaptative glucose-sparing”). This readaptation to fatty-acid metabolism, Dr. Phinney states, is the reason that endurance athletes on a ketogenic diet become effectively bonk-proof.


(Bob M) #9

That’s reasonable and helps to explain my ketones (once relatively high, now near zero). My body likely has figured out that if I’m using fatty acids, I don’t need as much “fuel” from ketones (or blood sugar).

It’s too bad fatty acids aren’t discussed more.