Evening all,

Starting to ride longer and further and I’m very conscious that I’m very reliant on carbs before and during a ride to keep me running well.

I’ve read a bit about becoming fat adapted and that im going to have to do a lot of zone 2 work whilst not very well fed to get better at going further without working so hard with my heart rate as high.

I’m aware this will mean I become slower in the meantime to get faster in the long run.

Does anyone have experience of making a conscious effort to adapt and how long did it take before you for back to carb fuelled levels of performance but with a lower heart rate?

+1 interested in this. Haven’t heard the theory before but it mirrors my experience of intermittent fasting i.e. I find i become much less sugar dependent.

Try fasted runs early in the morning. You will still use some of yesterdays carbs but you will start the reprogramming to use fat a bit more at higher heart rates. In truth, improving this is about doing long runs and taking in just enough carbs to burn fat. You never burn purely glycogen and sugars in a long ride as you simply couldn’t. The long term answer is go for longer runs over 3 hours and then you will burn lots of fat. At the same time if you are really wanting to train hard you must take in a large amount of carbs as you do not burn fat efficiently enough to fuel very high intensity rides. There you must have sufficient carbs on board or you will certainly bonk. If i’m doing a long sportive or enduro and I want to go as fast as possible then I will start swallowing glucose early on and keep doing so very regularly.

Doesn’t work for everyone and requires a process of adaptation. I managed fine on a regular diet for 4 days in the arctic down to -27c – the hard part was consuming the volume of calories, never mind worrying about their composition.

Get yourself over to reddit.com/r/keto. I’ve been on Keto which is a fancy way of saying fat adapted since October. I’ve lost about 17kg, 107kg down to around 90 but my scales ran out of battery two weeks ago so can’t give an up to date account.

I started the diet to lose weight after finishing my first and very painful half iron man at 107kg and deciding that enough was enough. Losing the weight has been great but the biggest advantage has been not needing to eat during extended exercise. I can now get back from a cycle in the morning with no more than some eggs for breakfast and forget to eat lunch, where before if I didn’t eat every hour on a ride I would feel awful.

YMMV and IAMNAD etc etc but it worked for me!

What you describe as “fat adapted” just sounds like being lighter and fitter! It also sounds quite difficult to properly manage and assess.

Going fully ketogenic is in some ways easier, as you control everything in your diet and you get good indications that you are in ketosis, but different people adapt differently and it’s not for everyone – I tried it last year and it had some benefits including lower weight, increased endurance and more stable energy levels: exactly what I was interested in. But there were a couple of parts that weren’t so good for me so I let it drop.

The most interesting thing was being able to step away from the idea that athletes must have carbs. And bulletproof coffee – I loved that bit.

So in answer to my question Tim how long did this process take?

Any observations as you went through a transition period/advice as what to look out for?

I get what happens at a cellular level and in some ways I agree it could be looked at as being fitter, but fitness has many different specifics.

I have great sprint fitness and if my glucose levels are up I’ve got decent fitness to sit with a fast bunch. So it’s not so much about my fitness as what energy source my cells are adapted to use. Being fairly carb dependent makes me pretty competitive on punchy climbs and rolling hills where you have to recruit a lot of power then back off bit as I’m a lot more efficient at taping into high power outputs for short periods of time than some of the guys I ride with who go out and do longer rides regularly. Probably as I’ve spent a lot of time on the mountain bike where you are on and off the gas a lot more than riding road which I’m moving over to.

I’m finding I’m not so great as you get into 6/7 hours in the saddle and there’s only so much food you can carry/get down you during a ride/race.

IME it’s as much about training adaptation and the long-slow-burn, as much about the diet. I have two mates who have gone keto, one very successfully and the other who is struggling to maintain any speed or high-intensity output. I did consider it, but I simply stuck to a balanced diet and regular rides of 12-24 hours – i have lost some of my top-end punch, but that probably as much down to the training. It really depends on the durations you’re planning to train for?

From what I have read the most important aspect in becoming fat adapted is diet, you need to reduce carb and replace with fat. Training in a low zone helps to burn greater % of fat for calories used but does not help that much to become fat adapted where your body uses fat for most of its engery all the time, especially if you are consuming a lot of carbs

If interested, check out Phil maffetone as some good info on there or a book that covers diet and training quite nicely is ‘primal endurance’ by Mark sisson

Can take quite a lot of effort and time but the pay of is you can ride a lot longer requiring less food during the ride. Oh and it appears to be genuinely quite healthy as you produce a lot less insulin but that’s a whole other topic.

I’ve read a bit about becoming fat adapted

no such thing, your body works a certain way with respect to carbs, fats and protein metabolism.

low intensity exercise pretty much fat is used as the main source of energy, as you start to increase your intensity then the body will switch to using carbs.

Think the OP’s terminology is maybe a little at odds with the modern interpretation of ‘fat adapted’.
I got the impression he’s not really after going keto, just improving his ability to ride a long way without relying only on glycogen stores + carb intake.

Does anyone have experience of making a conscious effort to adapt and how long did it take before you for back to carb fuelled levels of performance but with a lower heart rate?

From what I know of the process, you don’t get a lower heart rate – you just begin to burn a higher % of fat at higher heart rates. A lower HR for a given power would be a by product of being fitter rather than a change in fuel source.

I’ve been working at it for around a year with moderate success. I try to do my recovery rides and maybe a 2hr hr easy ride on nothing but water. Easy rides of 3-4hrs get short fuelled. Longer rides and intense rides still get fully fuelled.

I’m still definitely more carb dependant than others, but have definitely seen a notable improvement in sustainable pace once carbs are depleted.

Yeh absolutely that fifeandy.

Thanks for translating. No interest in Atkins, just getting a physical adaptation to riding less carb fuelled.

You say you’ve been at it for a year, can you elaborate a bit more about what you experienced on rides early on etc and how long before you noticed positive benefits?

Poah.. some literature would disagree. In the same way your body can adapt to training loads and get better at longer slower or shorter faster you can in some ways adapt to fuel sources (from what I’ve read anyeay) hence asking about people’s experiences.

You need to go keto, your body will use carbs as a priority over anything else. I’m in ketosis right now, how do i know? I have keto strips which you can buy online from pharmacies for peanuts.
How long does it take?Me personally 5-7 days, some people take a month though. Days 3-4 i have massive sugar cravings, by day 7 i don’t even look at or crave chocolate. Energy levels stay consistent all day, no ups and downs. I can eat as many calories as i want and not put on weight but i won’t loose weight u less I’m eating less than 2500calories but that’s with zero exercise. You have to eat a lot of green veg and be careful not to have too much protein otherwise in ketosis your body will turn excess protein into glycogen and knock you out. I buy meats that contain less than 0.5% carbs
I typically eat

Breakfast
2 bacon 2 sausage 2 eggs and some mushrooms cooked in butter.

Dinner salmon and a whole bag of rocket salad or mixed leaf

Tea chicken/steak with brocolli green beans

Supper minced beef with cheese grated on top.

I’m never hungry and probably eat too much protein but I’m never out of ketosis when i pee.

There’s more than enough calories in those meals for bike rides.

Poah – yes your body works a certain way and the term fat adapted can be misleading. But you can influence the % of fat burned at any given level of effort with the right diet approach and thus sparing your valuable glycogen stores.

At low efforts fat should be the highest % of fuel but this figure changes depending on you overall diet. So for example a hight carb diet person cycleing in zone 2 may use 50% fat 50% carbs they then change to a lowered carb diet and higher fat and then 6 months later at the same effort it may be 70% fat and 30% carbs hence they are more fat adapted.

Can use gas analysis which shows this.

My completely unscientific method was to ride progressively longer rides at a decent effort level and reduce the calorie intake progressively. It’s probably taken me a year but I can do a 3-4 hour high intensity efforts including periods above threshold unfueled, and longer periods at lower intensity. I’m not religious about it and I still take food on rides depending how I feel.. off out to ride 100k and about 1800m of climbing and will prob have one or two gels and one bar for all of that.

Thought this thread was going to be another ebike thread about people adapting to being fat.

Ho hum, as you were.

I think that it really depends upon what you call “riding for longer”, are we talking about changing from 2 hours to start riding 4-5 hours, or are you talking about riding 12 hours plus?

I think that you will see a lot written about these various keto diets and i think they may suit those people that are doing the long slow steady type of events more, where you are riding for 24 hours, but ultimately if you are wanting to ride 4-5 hours at a fairly quick pace, then a well controlled diet with a good balance of carbs is the answer.

As yourself, bearing in mind that they can afford the best sports scientists/ nutritionists in the world, how many pro-cycling teams had riders riding on a carb free diet at Milan – San Remo at the weekend, the longest day in professional racing on World Tour?

They will all do fasted riding to get the body to adapt to riding on less carbs/ more on fat, but none of them will be doing this full keto diet?

Poah.. some literature would disagree. In the same way your body can adapt to training loads and get better at longer slower or shorter faster you can in some ways adapt to fuel sources (from what I’ve read anyeay) hence asking about people’s experiences.

the only people that are going see a difference are the top end athletes. For the majority of us, doing low intensity work will make you last longer without having to take in carbs. This is easily seen when I ride with my son compared to on my own or friends.

Scud, yeh I get that. 2 hours is a sprint really and I dont need anything, barely water for that amount of time.

I’m talking about 6/7 hrs+

Up to 5 hours I can get away with my current metabolism just great.

In fact 5 hours seem to be a sticking point in that I think my liver and stored glycogen is done by then.

Good meal a few hours before hand and a whole soreen for a 5 hour ride usually eat half at 2 hours in then the other half at about 3hr30. Last 5 hours at a good pace no problem on that if I’m well fuelled before. Usually have a few min pork pies along the way for 5/6 hours too.

Did 7 hours the other day and took a lot of fuel along for the ride.. really felt it and needed all of it.

I’d like to be able to go out regularly at the weekend for 7-8 hours regardless cafe stops.

Does anyone have experience of making a conscious effort to adapt and how long did it take before you for back to carb fuelled levels of performance but with a lower heart rate?

I’ve done fasted riding – so longer slower rides without breakfast – start taking on carbs 45 mins into the ride. I’ve also done it with shorter higher intensity rides on an off-road commute.

It didn’t help me lose weight but it did radically improve my endurance.

your body will use carbs as a priority over anything else

At higher intensities. At lower, it’ll prefer fats. See this graph:

Where the graph starts to go up, that’s where the rider starts getting energy from carbs. Below that it’s fat (although a small amount of glycogen is used when metabolising fat iirc).

Zone 2 training is enough to move this upward curve to the right, but I suspect it’s more effective when riding fasted also. People who tend to be sprinters like to sprint, so naturally their graph has a short flat section, which is why we like to take on carbs and then use them, and then take on more etc. Sounds like the OP is a sprinter. Endurance based athletes (slow twitch, lots of Type I muscle) naturally burn more fat so end up thinner and like doing long rides, but can’t sprint so well.

I’m aware this will mean I become slower in the meantime to get faster in the long run.

Doesn’t quite work like that IME. You’ll always be slower fasted than you will well-fed. Your fasted performance will improve, but when you then ride with lots of carbs you’ll find your well-fuelled performace will also have improved.

From what I have read the most important aspect in becoming fat adapted is diet, you need to reduce carb and replace with fat.

For me, lots of zone 2 riding helped hugely, without changing diet.

I’ve read a bit about becoming fat adapted
no such thing

There is!

Does this zone 2 riding have to be for a long time? Or do multiple short z2 rides work too?

I usually get 2 rides a week in, one in a lunch time, one early Sunday and tend to just thrash my way round both. Wonder if there is any benefit in being more targetted, or if it just needs more time overall before specific intensities make a difference.

Does this zone 2 riding have to be for a long time? Or do multiple short z2 rides work too?

Overall yes. When I was being trained by a coach I did 10-12 hours a week. So ideally lots of long rides. I think they need to be at least 90 mins ish per ride though.

Wonder if there is any benefit in being more targetted

There is. Z2 aka base training does a different thing to thrashing. But it doesn’t sound like you have enough time to really do base training properly.

Ideally you’d have one or two lunchtime high intensity rides, and then your sunday AM ride would need to be long if it’s going to be slow. And possibly fasted. Also ideally on road. Base training off-road is really hard, because climbs tend to require more effort than you should be doing, and you can’t usually pedal hard enough on descents.

Doing a normal MTB ride slowly isn’t quite the same as doing base training. Base should be sustained and steady – so it feels really easy in the first hour but should feel hard to sustain by the 5th. Or if you only have three hours, increase pace slightly so you’re still feeling it in the third.

You say you’ve been at it for a year, can you elaborate a bit more about what you experienced on rides early on etc and how long before you noticed positive benefits?

I’ve taken a very cautious approach as my medical history makes me prone to weight loss, so riding on low/no fuel was/is something I didn’t want to just dive into.
This means i’ve also had no undesirable side effects either other than just feeling really low on energy towards the end of some rides (which is the whole point of the exercise – basically riding half bonked in a controlled way).

I probably didn’t notice any difference for the first month or 2, but gradually finding I can go further whilst feeling fresher on less.
Previously, once the fuel ran out, the pace dropped significantly and breathing was very heavy despite actual power output being low.
Now when I reach the point where i’m feeling really low on fuel, i’m able to sustain a solid endurance pace rather than performance tailing off horribly.

They will all do fasted riding to get the body to adapt to riding on less carbs/ more on fat, but none of them will be doing this full keto diet?

The odd one or two may be keto, but the vast majority are indeed training as you describe. I remember reading an article that Carlos Sastre would go on 6 hour training rides with 1 energy bar, have half 3 hours in, and only have the second half in emergencies.

Whilst certainly not full keto, you can however dig up several recent articles that show that many pro teams are now eating significantly differently day to day, and no longer massive bowls of pasta for breakfast etc.

Cheers, interesting thoughts there. 10-12 hours is going to have to wait about 12 years with the boys 🙂 – but always interested to make the best of what I have. I reckon I go too fast (relatively!) on the times I might get 3 hours plus, and not hard enough in the hour / 90 mins sessions, so don’t really train either end right.

it takes at least 6 weeks to become truly fat adapted, and you will only get there by cutting all carbs Except green leafy veggies, kale/broccoli/spinach/asparagus/cabbage, and upping your natural fats massively, ive been Keto for 2.6 years and can testify how good it really is for health And performance 🙂

Well I read this thread this morning and so went for an afternoon 3 hr road ride having had nowt to eat but a small breakfast, and took only water with me. It went well, which surprised me as I haven’t done any long rides (barring the Puffer in a team) for months. Normally I would make sure I was fuelled up for such a ride, and take a snack with me.

The weather closed in and I got a bit cold up in the Valleys, and when I got home I couldn’t get warm for an hour or so, despite tea, cake and a protein shake. So I must have been well glycogen depleted by then.

You keto guys, does it make your breath smell? Not that I would consider it anyhow, I did a 12 hr solo once and am not planning another.

smelly breath comes from over eating of protein and under drinking of water

My understanding is that breath stink comes from the acidic by product of burning fat cells.
I’ve been in keto for around 6 weeks and monitoring protein intake fairly carefully. My breath smells.

Althought I am a big fan of lower carbon eating and obtaining them from whole food sources for health and potential performance it’s important to find what works well for the individual as some people do not do well on really carb compared to others. Some people may kind full keto does not work great for them, a higher carb (but still low compared to typical western diet) may work better.

Also for pure performance using cards during an event and after can been useful. It appears that there is a general direction in sport of consuming less carbs overall but increasing during training or races.

Tim Noakes has spent most of his professional life researching and supporting high carb for performance but in recent years, after reviewing more recent research ,has changed his view. A pretty massive turn around and one that has brought him a lot of grief.

Unfortunately when there’s lots of money involved it muddys the water.

[video]https://www.youtube.com/watch?v=Nwd6InD2nDk[/video]