strange how this video is 2 years old?
EDIT: This was their previous experiment with running
He said "what if I told you..." so I'm out.
Guessing they were riding slowly?
He said “what if I told you…” so I’m out.
To be fair, that's just the words of a scientist who has had some media training and / or got better at using Twitter to attract attention. The 42-word title of his academic paper is unlikely to be quite as catchy.
It's a really interesting experiment. As long as you don't venture into anything anaerobic, you've got tens of thousands of calories at your disposal in your fat stores. It's just the not-anaerobic part that's tough - even a short climb when you've run out of gears, or accelerating away from lights, can feel REALLY tough when you're in ketosis.
Yeah that's my experience of riding with low carb stores (not zero!). I don't think it works well for me personally though as I'm heavily adapted to glycogen use. And well, just heavy in general.
I do wonder though if I should book myself a fortnight in say, the Netherlands, and just ride all day every day at z2 and eat no carbs, see if it sheds loads of weight.
Booked marked from a proper read later.
I did the 800 daily calorie thing for 9 weeks a few years ago to loose some weight I'd put on (middle age lethargy meets hip op had me put a load of weight on that needed shifting). I really surprised myself with how well I rode on very few calories. It was also something I got better at - not sure this that was a physical or phycological adaption. But I could eat a 300cal dinner in the evening and then eat nothing else and ride a 25 mile ride the next morning without suffering too badly. Yes, not mega fast and I would pop on the hills if not careful but it was far more possible than I thought it would be.
The data seems weird. Rider 1 reduced their bf% by 6% which is 4.8kg, but they only lost 2.7kg. Are we saying that on zero calories they built over 2kg of muscle over 5 days or have somehow overhydrated?
Riders 3 and 4 loose almost 10% of their mass, but only 2% of their fat. So burning muscle, or water loss? Where's the water %.
If you plot all of that, I'd bet there's barely a trend anywhere except for predictable weight loss and Ketone increase.
@molgrips don't underestimate the wind in the Netherlands, it's why they have so many windmills. A ride up the coast might be 3 hours out, 1 hour back, it's just like riding up a hill!
What is the point of this? Is it to understand the physiological changes that happen over the period, or to prove that it can be done, or to prove some point about fasting?
dinner in the evening and then eat nothing else and ride a 25 mile ride the next morning without suffering too badly
I do that every time I ride. I can't ride with food in my stomach as causes reflux issues so I ride early in teh morning (8ish) and never eat beofrehand. Never ride over 30 miles though which is probably why I get away with it I guess.
I do that every time I ride. I can’t ride with food in my stomach as causes reflux issues so I ride early in teh morning (8ish) and never eat beofrehand. Never ride over 30 miles though which is probably why I get away with it I guess.
I think the "300cal" you clipped off that quote was the important factor. Eating a 'proper' dinner and riding the next morning is pretty much normal.
He says the body "prefers it", but they averaged 10mph and there was no control group or comparator mentioned, so the body prefers it to what exactly? How has he concluded that?
"Key takeaway, the human body is designed to thrive and benefit from an occasional fast." How is that the key takeaway when the only data he has shown is during and directly after the event? His body may have been functioning or performing better directly before or not long after this study took place. What is the definition here of thriving or benefiting? In what way?
This is ****ing awful science and written up very poorly, which is a shame because it's an interesting experiment. As said above, none of the bodyfat measurements make sense when compared to the body weight measurements. Rider 5 has gained BF but lost weight, so all of the BF results are spurious at best.
To be fair, that’s just the words of a scientist who has had some media training and / or got better at using Twitter to attract attention. The 42-word title of his academic paper is unlikely to be quite as catchy.
Steve Bennett is a British gemstone expert, who has since focused on the health industry serial entrepreneur.[1] He is known for his online shopping businesses.[2]
"scientist"
Let these ****ers ride up a mountain in zone 4 with a few sprints Vs someone properly fuelled 5 days in a row. They won’t get anywhere if they are burning 4000 calories a day.
Key takeaway, the human body is designed...
Say what now?
The human body has evolved to be flexible and work in many situations.
to loose some weight
Lose
Riders 3 and 4 loose almost 10% of their mass
Lose
Key takeaway
I bet he'd have loved a takeaway after 5 days of not eating
This smells like junk 'science' from Mr @HealthResults.
That said, riding 50 hilly miles at a steady pace without snacks is more standard ride and works for me.
I think the “300cal” you clipped off that quote was the important factor. Eating a ‘proper’ dinner and riding the next morning is pretty much normal.
I didn't include it because I eat tiny meals in the evening as anything big causes issues sleeping. So still applies.
they averaged 10mph
There you go, no wonder they didn't need to eat. I don't think I have averaged even close to as low as 10mph since I was about 5 years old!
I didn’t include it because I eat tiny meals in the evening as anything big causes issues sleeping. So still applies.
So how many calories do you eat in the 24hrs before the ride then?
But maybe they were only averaging 10mph because they were riding Penny Farthings, while generally heading in a south west direction against the prevailing wind, doing 250W+ for 10 hours? 😆
So how many calories do you eat in the 24hrs before the ride then?
Haven't got a clue and don't really care. The point is all my rides are fasted in as much I haven't easten anything for around 14 hours. I don't ride far but I ride fairly fast.
The average 10mph makes the whole 'experiment' pointless anyway as of course you can do that for a while.
So what exactly is he trying to sell here, as that is where it seems to be going?
There’s no “I feel really shit” index on those charts.
I have a couple of mates who went ‘keto’ - even after a few months, they’re turn up on the group ride, ride steady for a couple of hours. We’d got to a cafe where they’d eat non-carbs and then still bonk on the way home, sometimes reduced to near walking pace - much to the amusement of the rest of the group at their self-induced plight.
There’s a lot to be said by adaptation and running ‘lean’ in comparison to what some nutritional ‘experts’ state you need to consume, but as carbs have a role in turning blood glycogen into energy and getting the knock / hitting the wall isn’t really conducive to having a good day on the bike.
Haven’t got a clue and don’t really care. The point is all my rides are fasted in as much I haven’t easten anything for around 14 hours.
I think this is the general definition of fasted, but there's a bit more to it. You'll have stored glycogen, and you'll use that on your morning rides. Then presumably you'll eat carbs after that and replenish the stores. However, if you don't eat carbs (or don't eat enough) you'll deplete your stores further and that's when the different stuff starts to happen e.g. ketosis, it promotes hormonal changes.
I have a couple of mates who went ‘keto’ – even after a few months, they’re turn up on the group ride, ride steady for a couple of hours. We’d got to a cafe where they’d eat non-carbs and then still bonk on the way home, sometimes reduced to near walking pace – much to the amusement of the rest of the group at their self-induced plight.
I really don't think everyone's suited for this. Just like everyone's not going to benefit the same from sprint training, we're not all capable of becoming a Chris Hoy.
You can do a couple of hours without eating at a good pace. E.g. commuting to work I used to do upto 2 hours without eating. You'd not attempt to work all day then ride back without food, nor would I now with an hour each way. Ride to work fasted, eat food, ride home.
Now at 10 mph, could manage some distance, but not at 16-20 mph.
We’d got to a cafe where they’d eat non-carbs and then still bonk on the way home, sometimes reduced to near walking pace – much to the amusement of the rest of the group at their self-induced plight.
I thought the point was that you were deriving energy primarily from ketones rather than glucose/glycogen? If they are hitting the wall after a couple of hours, it suggests to me that they were not actually fat-adapted at all, not in ketosis, and that it was just a standard bonk from depleting and not replacing the glycogen they were actually using. The body will convert fat into glycogen stores, but the actual aim is to be more able to burn it contemporaneously as an exercise response.
When I could be bothered with a Keto diet, I could ride literally all day at a steady pace on a handful of nuts and beef jerky (and quite possibly didn't even need that). Gave it up because it was dull and restrictive, but I miss that ability.
When I could be bothered with a Keto diet, I could ride literally all day at a steady pace on a handful of nuts and beef jerky
That backs up my theory that people are different and some will respond better to ketosis than others.
I once ran the Yorkshire 3 peaks fasted, i.e. I got up in the morning, ate nothing, did it then ate afterwards at about 7pm. No ill effects, however it was done at very low intensity as I was with my wife who's a much slower runner.
I thought the point was that you were deriving energy primarily from ketones rather than glucose/glycogen? If they are hitting the wall after a couple of hours, it suggests to me that they were not actually fat-adapted at all, not in ketosis, and that it was just a standard bonk from depleting and not replacing the glycogen they were actually using. The body will convert fat into glycogen stores, but the actual aim is to be more able to burn it contemporaneously as an exercise response.
Just to clarify, these guys are very experienced Ironman age-group and multi-Ironman World champs with years of experience but in the process of getting fat-adapted they were putting themselves through a fairly tortuous process, but it was fun to watch 😂 even though our rides were taking hours longer.
but in the process of getting fat-adapted they were putting themselves through a fairly tortuous process
I guess they were reprogramming a specific fuelling method that their bodies had been conditioned to expect over many years, whereas I spent years eating any old shite before 'exercise', so my body just worked with what it got! 🙂
Not read the article but spotted the " averaged 10 mph" on road? Jeepers that is slow. I do more than that on road and can get close offroad towing a trailer of camping kit.
On my first long tour I lost 2 stone over 11 weeks. Mostly in the first half of the tour at around half a pound a day. So I must have been burning fat every day.
The odd thing wasn't the weight loss but the fact it happened while I ate as much as I wanted. Other than the expected fatigue when riding a loaded touring bike uphill for a few hours here and there or into an all day headwind I never felt any lack of energy.
I went on tour after quitting a sedentary job with coffee and biscuits available in the same room. Totally lost my sweet tooth on tour though enjoyed a beer or two almost every night.
On my first long tour I lost 2 stone over 11 weeks. Mostly in the first half of the tour at around half a pound a day. So I must have been burning fat every day.
Of course - you burn fat all the time. When you exercise harder, you burn a higher percentage of carbs, but it goes from say 60/40 to 40/60.
Key takeaway, the human body is designed…
The human body is adaptable and you can force it to fuel in different ways but its not healthy or good for exercis. Mixed diet with decent amount of short and long acting carbs is best
Also most folk who claim to do keto are not.. putting your body into ketosis is not a healthy thing to do despite all the junk science about
500km slooowly. Fine. Fat burning and plenty of electrolytes makes sense. Now try and ride that in sun-18hrs. My best 12hr TT was 452km and 200W average (2.8w/kg) I ate a lot of calories. At 1.4w/kg I could imagine metabolism would be very different.
I could do it if I had the time. Give me a couple of weeks to get fully fat adapted and at that pace it’s not even a challenge.
This is a much tougher challenge I can’t even imagine running 118 miles let alone with zero calories
Not sure the point it proves. If you don’t eat and do exercise you’ll lose some weight. That’s kinds of obvious.
Personally if your not eating I think it’s more important to do weights to mimimise muscle loss rather cardio.
Not read the article but spotted the ” averaged 10 mph” on road?
Yes, which as I said debunks the whole thing. 10mph on the road is pretty much not even cycling. Bit of pedalling, bit of coasting, 30mph down hills allows 4mph up the hills etc,. It is such a steady pace that it is.
The human can do all sorts of things while not eating for days (see people that are in famine!) but "proper" cycling would not be one of them.
What is the point of this? Is it to understand the physiological changes that happen over the period, or to prove that it can be done, or to prove some point about fasting?
Content generation for a YouTube channel 🙂
Shock horror you can ride without eating for 5 days but you won’t be very fast but you may get more viewers for your channel.
Been on a hybrid keto diet for several years now. Less than 30g of carbs for 6 days then a carb up on a Sunday. Started doing it in my gym days and just stuck to it. Helps keep my weight stable. I’ve got an incredible sweet tooth so used to find that on a high carb diet I’d end up eating to much crap. By eating the way I do I can control my weight but one day a week I’ll eat anything I fancy so don’t deny myself of things I like. Be it chocolate or cake 😁
All my training rides during the week ( sometimes high intensity up to 3hrs) are carb free, often fasted. In fact I’ve done several 6hr, 100 mile + rides at a decent pace on the roads without carbs and sometimes even fasted. I think it helps me with the racing I normally target (long distance TT’s) in that although I do take on carbs during the race I’m able to use more of my fat as my primary energy sauce, only dipping into glycogen as and when needed.
