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Any Cyclists Here. Am Pre-diabetic, Have Dropped Carbs But Feel Weak.

B

Becr

Active Member
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Hi all,

I have been told I am pre-diabetic. Since then I have adapted my diet by swapping sugary carbs for slow release food. I have spread my carbs out across the day better too. I love cycling doing my first sportive a couple of weeks ago. I also love Watt biking. I have noticed I have no real power anymore, my thighs burn and I can't push hard. I am seeing a dietician at the end of the month but wondered if anyone else had experienced the same. I was also told I am slightly anaemic which probably doesn't help things. Thanks!
 
Hi @Becr, that's a few issues to cover there but here goes:

Yes there are lots of cyclists here but I'm not one. I'm sure they will drop by later on. It sounds like a great sport and way to exercise.

Well done on the carb changes - it sounds like you may need to increase fats and proteins to replace energy you need for cycling and everything else. Others here can advise on details.

For now, you might need to reduce your cycling a bit, until you have found out more about the anaemia and made some more food changes to help your energy levels.

I'm not confident the dietician will give you the latest advice on carbs but I could be wrong, you never know. Most of them give outdated advice about carbs and fats that does not help prediabetics prevent becoming diabetic.

It's a good idea to ask for a printed copy or online access to your blood test results. The actual number is much more useful to you than "fine" or "low." Anaemia may affect HbA1c (diabetes) test results, so your GP may need to order a different kind of blood test at the lab.

In my personal experience, it's also important to treat anaemia as early as you can with iron supplements, since it can take a long time to build up iron stores again. Hopefully your GP can advise.
 
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Hi and welcome!

How long have you been low carbing? There is a definite transition period during which people experience less stamina and strength, while their bodies transition into ketosis and Fat Adaptation. Nutritional Ketosis can usually be achieved quickly, anywhere from a couple fo days to a couple of weeks, depending on how low carb you go, and how big your glycogen stores are.

However, true Fat Adaptation is a slower business, and you won't get the full benefits (endurance and steady energy) until you have been in ketosis for a good few weeks, possibly months. Volek and Phinney talk about this in their two books 'The Art and Science of Low carb Living' and 'The Art and Science of Low Carb Performance'. In these books they describe the process of fat adaptation, how long it takes, and have done studies showing that their study group only achieved got back their full performance levels after around 6+ weeks, at which point they also ceased 'hitting the wall'.

Since I am certainly not an athlete of any description, I wouldn't dream of giving you advice on training, but I do recommend both of those books, since Voleck and Phinney have been working with athletes and doing low carb studies on them for over 20 years.

Regarding your anaemia, I would urge you to seek medical advice, since no one here should be offering advice on it, although they may be able to speak of their own personal experiences.
 
Not a cyclist (other than my 5 mile commute) but think a look at this book might help you both practically and to understand how to transition from running on carbs (glucose) to running on fat. The pioneering researchers Stephen Philley and Jeff Volek have also done loads of work on endurance s;ports and low carb as has Professor Tim Noakes who used to promote the high carb route until he became diabetic himself:
https://smile.amazon.co.uk/Primal-Endurance-Mark-Sisson/dp/1939563089/ref=asap_bc?ie=UTF8

In short aaenemia aside getting your body on fat rather than sugar takes time but will be beneficial and should not be to the detriment of your performance unless you are a sprinter in which case there is less evidence in support of going low carb!
 
Hello! thanks for the helpful reply. About two weeks ago I halved my carbs through the day so probably hitting around 100g of carbs. But I do a lot of physical activity, my job as a photographer is very physical so I think that is a low amount for me. My blood sugars are stable at around 4.8 - 6. I have cut out all sugary sports drinks that I would use to give me a boost when I felt knackered before an interval session or hard session on the bike. Now when I try to go hard I just run out of energy and feel rubbish. I do something called Watt biking where you can see the power you are putting out and mine has really dropped. I guess I just have to keep cracking on. Will I reach Ketosis on 100g of carbs? I guess if I am burning them up?
 

Hi,

There are some people who find they can get into ketosis at 100g carbs a day. I think they tend to be very fit muscly active athletes. There is a generally accepted idea that you can pretty much assume that you will be in ketosis at 50g carbs a day, or less. While the more sedentary amongst us (waves cheerfully from her armchair) may need to be below 20 g carbs a day to get there.

Did you actually WANT to be in ketosis?
The reason I ask is that it certainly isn't obligatory! I was reading an article a couple of weeks ago about how if you drop your carbs somewhat, you could experience a lack lustre loss of energy, without hitting low enough carbs to yeild the benefits of ketosis. I will see if I can backtrack and find the article, because it explained things really well.

Here it is
https://paleoleap.com/energy-paleo/
It is talking about Paleo, which is similar to Low Carb, so nearly everything they talk about is directly transferrable to a low carb way of eating.

Basically the choice is to fuel your exercise with carbs or fat. The latter takes being in ketosis, the former requires enough carbs to provide the fuel. Both of them require enough energy intake. And 100g carbs a day may put you right in the zone where you haven't hit ketosis, and aren't eating enough carbs/calories to fuel.

You are, of course, in the best position to assess if any of the above is relevant to you - since you know exactly how you are feeling, and what you are eating.

Hope that helps!
 
Again thank you SO much. I have been in Ketosis before when I tried Low Carbing years ago because I was suspicious that I might be experiencing problems with sugar and carbs. I found being there quite uncomfortable personally, I became very agitated and anxious. I was also waking every night at around 3am. I lost so much weight. I am pretty light anyway so I'd prefer not to lose more weight. It proved though that sugar and carbs are **** for me because the weight feel off effortlessly and I struggled to have an appetite for food.
 
I have not done sportives for at least four years but have been getting myself back into Ketosis lately and intending to restart once again. I've been working in the United States so I also have many pounds to shift first. I found on the 'Epic' courses I would Bonk around 70 miles when I was using carbs and need to ram carbs down my throat just before that happened. I then went into Ketosis around 20g a day whilst still doing around 300-400 miles a week never really having a great problem.

My natural cadence is only around 72rpm so I am more a Diesel type of rider and did find my peak wattage was lower until I fully tranistioned into Ketosis which took a long time 2-3 months. I would love to do the higher cadences but just cant whether I am on Carbs or in Ketosis. Once in Ketosis I could do a full 'Epic' without stopping or craving for food.

I did the the shorter London to Brighton on a fast as was too busy racking the bike on the car etc and forgot to eat before skooting down to London for the start and it really didn't matter. No Highs no Lows just cycling.

Now I am even more missing it and need to get some more miles in to shed these extra flabby bits
 
Thank you! Impressive what you have achieved on your bike. Yes, I was previously getting really good peak watt readings and feeling really strong uphill (helps that I have good power to weight ratio) but now I am just all limp . I bonk really quickly, after about 45mins. And my thighs just scream if I go up a steep incline. I am only two weeks into dropping my carbs down so I guess I need to be patient. I am also paying to see a sports dietician at the end of the month so that should help.
 
Hi, could you not eat a few carbs prior to cycling? you will likely find you will burn them off during the exercise. I'm prediabetic and my blood sugar reduces a lot after cycling and thats including having a carb snack prior to it.
Or you can go the whole Chris Froome thing and wait until your body completely learns to use fat as an energy source (i believe he is an ultra low carb eater).
 
In your shoes I would cut the carbs at least in half, switch to a 16 /8 or 16 / 6 eating pattern to speed up the transition to fat burning mode. Once you are fat adapted (if you go down this route) your performance should come back up, endurance improve with no requirement for gels etc.
 
I find that carbs are carbs - fast or slow release it makes no difference.
Are you eating enough fat now? Many people make the mistake of removing a sizable amount of their daily food intake without regard to their needs - and you might benefit from having a daily vitamin and mineral supplement just to top up any deficiencies. The micronutrients in foods these days are measurably less than they were a couple of decades ago.
 
Hi! I have tried this but sadly I am still getting that burning, lactic feeling in my legs and my heart rate is really high.
 
I have started upping fat this week I am going to see a dietician at the end of the month who also specialises in sports nutrition so I will ask her about more fat etc. Have been keeping a food diary along with my blood sugar readings. Thank you so much!
 
I am a leisure cyclist but there was something interesting on the TV last week . If you believe what you see on the TV ( in the recent BBC programme about carbs ) it is possible to get the benefit of the sport drink on your performance but not take in the Carbs . What you do is swill your mouth for 10 seconds part way through your exercise (they did it twice in a 30 minute static bike session )and spit out the drink and do not swallow but drink water to keep up hydration. Apparently your body get fooled into giving you the performance of the sports drink without the calories. Might be worth a try to see if it works for you. As you want to keep weight up I would also suggest the idea of increasing fats if you like something olives and or nuts might be worth considering as those will give you calories without many carbs.
 
Becr said:
Hi! I have tried this but sadly I am still getting that burning, lactic feeling in my legs and my heart rate is really high.
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Hi @Becr, are you referring to your heart rate during exercise, with your resting heart rate being within the normal range for your age?

I am no sports medicine expert (my idea of sport is playing an afternoon of social ladies cricket once a week in summer, fielding close in so I don't have to run as much, lol). But I know that professional trainers carry out a basic health check before starting a programme and they measure resting heart rate, blood pressure etc. Of course, you want your exercise heart rate high enough to help you achieve your goals, but hopefully not so high that it's an issue.

Good to see you are seeing a sports dietician as opposed to a regular one, since IMO there's more chance the dietician is up to date. If you can find out your iron blood test result (and previous test if available) and show it to the dietician, I think they would find it useful info.

Keep up the good work! You are an inspiration.
 
Bless you for your lovely response. I am just so determined to stay out of the Type 2 zone as my dad and brother are both type 2 and really don't take care of themselves. My ferritin level was very low on my blood test but B12 sky high so that is another thing to talk with the dietician about. I am someone who can get quite gloomy without exercise as it gives me an endorphin boost
 
Thanks @Becr. I haven't focused much on the T2 side of things because others are responding about that, but checking that your heart rate is within safe limits is a separate issue. I don't know much about heart health screening, just that nurses record heart rate when they do other observations like BP etc.

In my experience, my ferritin level fell to 17 (30 is the threshold used here for anaemia) and I felt very ill. If it dropped much more than that I would have started to potentially need some kind of infusion/transfusion (sorry I don't remember what was actually said). It took many months of treatment to get it back over 30, so the sooner I started the better.
 
Jenny, thank you again My ferritin level is at 8!! The doctor didn't seem to be worried and told me to take something called Spatone which is a very low dose of iron but easily absorbed. I think when I spoke to the doctor (a locum) on the phone he was more keen to discuss my HbA1c. I have felt so low over the last year or so too but just assumed it was my hormones as I am 45. At least I feel now I have something to explain how pants I have felt and I am throwing everything at getting it sorted. I wear a heart rate monitor when I cycle. My heart is working heart and I notice it takes a while to recover compared to the other riders (we do something called Watt biking where you are all linked up to a computer screen and can see each others stats). I will go and talk to my doctor and ask for something stronger for my iron!
 
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