Getting back to exercise!

[The_Bowlii]

Good stuff, and yes mistakes are part of the process.



I certainly eat early, if I leave it until my blood sugar on the libre is showing ~5 my power and stamina both fall off a cliff and I'm in trouble (likely already marginally hypo with the lag) - it depends on experience of what your blood sugar response is like, but I certainly aim to eat early and avoid dropping down too close to being hypo.

I also need to eat significantly more than a single jelly baby every 10-20min, more like 60g/hr (which I guess is only 12 jelly babies an hour, so not that much more...) For me that's usually a brunch bar and handful of sour sweets every 20-30min usually spread out a bit while I'm riding. I also try to eat savoury food from time to time - part-bake rolls are good carbs-bang-for-volume-buck (bacon rolls are great if I can be bothered to prepare them pre-ride, otherwise ham rolls it is). If I don't pay attention I'll need to eat more fast acting sweets to pull the levels up, though I don't much like having to eat lots of sweet stuff when hours in so this is not ideal.

Thanks @SimonP as always. Did Tour de Zwift stage 1 this evening eating a banana and drinking some lime cordial with no IoB since lunchtime and no food for 5 hours. Levels all fine which hopefully indicates I‘m getting the hang of it. Good call re bacon roll - that can be my target for next time I’m out!

 

[SimonP]

Thanks @SimonP as always. Did Tour de Zwift stage 1 this evening eating a banana and drinking some lime cordial with no IoB since lunchtime and no food for 5 hours. Levels all fine which hopefully indicates I‘m getting the hang of it. Good call re bacon roll - that can be my target for next time I’m out!

I've done some longish rides (6h) without eating as my blood sugar never started to drop. While I was pleased that I'd judged (lucky strike some might say) my basal correctly, I was pretty tired and performance wasn't up to much after about the 5h mark, so I now prefer to err slightly further on the side of needing to eat something and taking a bit more basal in the morning.

It is a case of trial and error though, sounds like you're definitely on the right track 🙂

 

[pistolpete]

Thanks @SimonP as always. Did Tour de Zwift stage 1 this evening eating a banana and drinking some lime cordial with no IoB since lunchtime and no food for 5 hours. Levels all fine which hopefully indicates I‘m getting the hang of it. Good call re bacon roll - that can be my target for next time I’m out!

Thats great news, so daunting to begin with but fantastic your getting on top of it.

 

[The_Bowlii]

Evening all. Quick update on the week. The Zwift ride was a real confidence booster and not far off my pre-diagnosis stats. I seemed to get the food and recovery about right - basically no insulin required for food taken during exercise and meals for the next 24 hours at half the normal bolus level. Sunday ride tomorrow with my lovely wife with a coffee halfway round is planned. Will probably take just 20% bolus with breakfast and see how it goes. Got a frame bag stuffed with gels and bars just in case…

Played squash several times this week too. 20g carbs up front (banana), 20g halfway through (gel) and sipping on 200ml orange juice diluted up to 500ml seems to work well (thanks @helli). Never eaten so much during exercise but hey ho, seems to work!

Best wishes everyone.

 

[SB2015]

You will gradually find what works for you @The_Bowlii and this will change with time, as well as with intensity of exercise. We just do the best that we can to match our insulin to each circumstance, and tapping inot the experience of others on here can be very helpful.

 

[The_Bowlii]

Successful ride this morning. Only 2.5 hours and a coffee halfway round but managed to keep levels within range through a mixture of snack bar, jelly babies and dilute orange juice.

Here‘s a question for you…I never used to bother eating and drinking when on my bike for anything around 2 hours in the saddle but now I’m eating to maintain glucose levels. What was my body using for fuel previously and why did I never suffer from hypos / the dreaded “bonk”. Confusing!

 

[pistolpete]

Successful ride this morning. Only 2.5 hours and a coffee halfway round but managed to keep levels within range through a mixture of snack bar, jelly babies and dilute orange juice.

Here‘s a question for you…I never used to bother eating and drinking when on my bike for anything around 2 hours in the saddle but now I’m eating to maintain glucose levels. What was my body using for fuel previously and why did I never suffer from hypos / the dreaded “bonk”. Confusing!

Fat, ketones and carbohydrates stored in the liver. In desperate situations your body will breakdown muscle and use that as fuel too. "Healthy people" as a rule dont go hypo your pancreas and liver see to that.

 

[The_Bowlii]

Fat, ketones and carbohydrates stored in the liver. In desperate situations your body will breakdown muscle and use that as fuel too. "Healthy people" as a rule dont go hypo your pancreas and liver see to that.

Thanks @pistolpete - I assume then that as the pancreas isn’t working, it can’t trigger the liver to release the stored energy. In that case, I’m going to have to get used to eating more frequently on the bike as that’s going to be the only source of additional fuel beyond pre-ride blood glucose.

 

[SB2015]

I am not sure about the science of it all, but I think even though our pancreas doesn’t produce insulin, our liver will still dump glucose for us when needed, and also in the morning when with the feet on the floor raise glucose levels.

 

[SimonP]

Successful ride this morning. Only 2.5 hours and a coffee halfway round but managed to keep levels within range through a mixture of snack bar, jelly babies and dilute orange juice.

Here‘s a question for you…I never used to bother eating and drinking when on my bike for anything around 2 hours in the saddle but now I’m eating to maintain glucose levels. What was my body using for fuel previously and why did I never suffer from hypos / the dreaded “bonk”. Confusing!

It sounds like you've still got "too much" insulin on board from basal and any residual bolus.

Too much is a relative term though, you don't actually want completely stable and flat BG while riding as then you can't eat (or need to think about some very small bolus quantities, which may or may not mean you need to eat lots). Better to end up with a gradual downward trend during a ride and to eat to cover that/ensure you don't bonk in the non-diabetic (they don't know what it's really like 😉) sense 🙂

 

[The_Bowlii]

It sounds like you've still got "too much" insulin on board from basal and any residual bolus.

Too much is a relative term though, you don't actually want completely stable and flat BG while riding as then you can't eat (or need to think about some very small bolus quantities, which may or may not mean you need to eat lots). Better to end up with a gradual downward trend during a ride and to eat to cover that/ensure you don't bonk in the non-diabetic (they don't know what it's really like 😉) sense 🙂

Morning @SimonP. Thanks for the note. Yes, I must have too much IoB when riding otherwise I’d have to tow a trailer with food in it to do a big ride! I’m taking 1 unit insulin for 25 grams carbs so will knock it back further this weekend. Did Zwift last evening with no insulin, ate a banana up front and sipped orange juice which worked a treat. It might be Sunday rides with no bolus is what’s required but taking it down slowly just to be sure.

 

[SimonP]

I think the interesting bit is what happens once your liver runs out of glycogen (at least that's what I theorise is happening), once you're ~3h+ into a ride - IoB left over from treating breakfast/pre-ride nerves/dawn phenomenon seems to have a significantly different (smaller) effect to IoB taken later in the day.

 

[The_Bowlii]

I think the interesting bit is what happens once your liver runs out of glycogen (at least that's what I theorise is happening), once you're ~3h+ into a ride - IoB left over from treating breakfast/pre-ride nerves/dawn phenomenon seems to have a significantly different (smaller) effect to IoB taken later in the day.

I don’t know but guess I’m going to find out! Really looking forward to the day I can get out and do 6 hours, lunch in the middle and not be panicking the whole time with too much IoB or not enough food. I’d just joined Audax UK before diagnosis which is ironic… . Did the NC500 in May so also want to get back to being able to do similar. Ups and downs along the way but it doesn’t seem impossible now.

 

[SimonP]

NC500 sounds like fun 🙂

Don't worry, I'm on the same journey, I've done a pair of 200km+ rides now over the past couple of months, and few 100 mile rides in addition this year and last, plus standard 100km+ rides other weeks.

I still take far too much food with me, but I think I can safely reduce this quite significantly if I have a planned stop every 100km, which is where doing an organised Audax might make some sense with food available at controls (the 100 mile+ rides I've done to date have stopped at friends'/family for food part way - visiting people was also a good reason for sitting on the bike for 7h+, though the sunshine and ticking veloviewer tiles helps too 🙂).

As I started riding during lockdown I almost invariably ride on my own and I've never stopped anywhere where I had to let my bike out of my sight and would probably prefer to bring enough food with me if I don't have a planned stop just in case I can't find anywhere I'm happy with - I realise that stopping at petrol stations/supermarkets is the done thing when Audaxing. I guess it will be less of a concern once I've done it once (using e.g. a lightweight café lock.)

I'm now feeling fairly relaxed about BG control over those sorts of distances/durations, but also feeling much more relaxed that unlike in normal life, if I start going low while riding, it will stop and I won't go any lower if I simply stop riding (or at least start crawling along towards somewhere I can source some food.) This is very unlike normal life where blood sugar dropping means potentially quite large amounts of food is required within a short time (because there's almost always IoB and a drop means a misjudgment). Therefore my concerns about needing to carry massive quantities of food (which are based on memories of my early days riding with full basal and residual bolus on board) are fading somewhat.

That was lots of waffle, but the message is it gets easier very quickly, and as with most long distance riding (afaiu and in my experience) it's mainly psychological fear of what might go wrong (running low without any food available being my concern), which is quickly kicked into touch by the realisation of what actually happens/how much you do need to eat, and when something unexpected does happen with blood glucose you deal with it and don't worry about it the next time round.

 

[The_Bowlii]

Thanks @SimonP. I am on fixed dose basal (Toujeo) so manage it all with basal (Fiasp) at the moment. I have drastically reduced insulin to about 1:25 if I’m about to go out cycling and that stops me dropping so quickly but perhaps room to reduce further still. I’m doing it stepwise at the moment so I’ll see.

When you head out, do you have food before you go (and any insulin?) on the basis you’ll burn it as fuel and then top up en route with bars, gels and drinks? I’m thinking if I have a big breakfast that should do me for about 90 mins before I need to start eating.

Sorry if I’m repeating myself - but overwhelmed at the moment with the whole situation.

 

[SimonP]

Don't worry, it's quite understandable to feel a bit overwhelmed, also I've posted loads of stuff, so it's probably quite hard to sift through what I've written/what I think. Do bear in mind that we're all different, etc., etc.

This mammoth effort is probably not going to be that easy to digest either, sorry!

I think you will probably need to drop your basal for longer rides [edit: ah, of course Toujeo is a very long acting insulin, so this is not so easy to do without changing to another insulin - so perhaps try bolus elimination first and see how you get on], as otherwise you will end up needing to eat loads in the 2nd half (once your liver has depleted its glycogen). There are caveats (of course), if you're stopping part way and can eat a decent amount, then you can boost your BG up and counter-act this. I ride to work (40km each way, not every day!) without reducing basal, because I know I will be there for a while and can eat/sort BG out, so it's effectively just a pair of 40km rides. I'd probably be happy with an 80km ride with normal basal, but would take a decent amount of food that I'd need to eat in the second half.

Onto the main question, do I eat and do I take bolus:

If my blood sugar is stable and in range, I will always eat something uncovered before I leave. If it's lunchtime I'll have something to eat (say 40g carbs - e.g. a sandwich) and ride, if it's in between meals I'll have a cup of coffee and a couple of biscuits (say ~25g carbs total). I do this in order to give my BG a quick bump up that will hopefully counteract the drop caused by exercise. This is mainly as it's more pleasant to eat at home than while pedalling 30min into the ride, so I may as well do it before I leave (and save the space in my framebag too). In the case of lunch I'm hungry so want to eat anyway but not take any bolus - I will therefore move lunch forward/backward to fit a ride if needs be.

If I'm high (and not dropping), even at lunchtime (and I'm hungry), I won't eat but will expect to eat during the ride, depending on how long it is. I won't generally do a correction and ride, unless very high, but that usually means I'm unwell so I won't be riding anyway.

I rarely leave at supper time, as I don't want to ride through the night and also because this tends to be my large meal of the day, so I will need to take some bolus. I do it (night rides) so infrequently that it's hard to remember, but I would guess I'd take perhaps 1/2 the usual dose (and I already split my dose for my evening meal, so this may only be 1/4 of the usual dose), and accept I may peak in the low/mid teens - this is similar to what I try to do for badminton in the evening.

Breakfast departures are different - I used to head off last year (for 140km+ rides) and eat breakfast (~35g CHO porridge) uncovered, which worked as long as I got out the door fairly quickly. I would end up peaking in the low to mid teens, then dropping to need to eat after ~2h30. However, this year, I have dawn phenomenon, so if I do this I end up shooting up to 20mmol/l+ which isn't ideal, and then I take 1U or 1.5U of bolus and end up dropping quite quickly (though this complete process usually takes on the order of 2h30). I can't say I've got this quite sorted, but I'm getting better at it, and I now try to take enough bolus to cover the dawn phenomenon part (i.e. the same quantity as on a normal day) and perhaps part of breakfast. This gave me a peak of 14mmol/l iirc on the last 200k ride which I thought wasn't too terrible, and then it gently dropped down into single figures.

To to summarise my thoughts regarding bolus - I try to avoid it completely except for fixing dawn phenomenon. I also try to avoid having any residual amount on board to avoid going low rapidly during the ride (I will drop anyway from basal, but I don't want it to drop through the floor which can happen with bolus IoB). I can live a bit of bolus IoB and needing to sort this out on short rides (an hour loop at lunchtime with left over from morning coffee, or my ~2h ride back home from work with some left over from lunch) but I know I will need to eat.

Having any significant amount on board is bad news IMO - I find my BG drops rapidly and I then need to eat quite a lot quite quickly to stave off/recover from a hypo, and it's then not much fun continuing to eat while you continue the ride. On my first 100 mile ride I stopped for lunch (sandwich, biscuits, coffee) and took ~3U to cover about half the total carbs. On my ride back I was eating constantly and bumping along just above hypo, wasn't much fun!

 

[The_Bowlii]

Don't worry, it's quite understandable to feel a bit overwhelmed, also I've posted loads of stuff, so it's probably quite hard to sift through what I've written/what I think. Do bear in mind that we're all different, etc., etc.

This mammoth effort is probably not going to be that easy to digest either, sorry!

I think you will probably need to drop your basal for longer rides [edit: ah, of course Toujeo is a very long acting insulin, so this is not so easy to do without changing to another insulin - so perhaps try bolus elimination first and see how you get on], as otherwise you will end up needing to eat loads in the 2nd half (once your liver has depleted its glycogen). There are caveats (of course), if you're stopping part way and can eat a decent amount, then you can boost your BG up and counter-act this. I ride to work (40km each way, not every day!) without reducing basal, because I know I will be there for a while and can eat/sort BG out, so it's effectively just a pair of 40km rides. I'd probably be happy with an 80km ride with normal basal, but would take a decent amount of food that I'd need to eat in the second half.

Onto the main question, do I eat and do I take bolus:

If my blood sugar is stable and in range, I will always eat something uncovered before I leave. If it's lunchtime I'll have something to eat (say 40g carbs - e.g. a sandwich) and ride, if it's in between meals I'll have a cup of coffee and a couple of biscuits (say ~25g carbs total). I do this in order to give my BG a quick bump up that will hopefully counteract the drop caused by exercise. This is mainly as it's more pleasant to eat at home than while pedalling 30min into the ride, so I may as well do it before I leave (and save the space in my framebag too). In the case of lunch I'm hungry so want to eat anyway but not take any bolus - I will therefore move lunch forward/backward to fit a ride if needs be.

If I'm high (and not dropping), even at lunchtime (and I'm hungry), I won't eat but will expect to eat during the ride, depending on how long it is. I won't generally do a correction and ride, unless very high, but that usually means I'm unwell so I won't be riding anyway.

I rarely leave at supper time, as I don't want to ride through the night and also because this tends to be my large meal of the day, so I will need to take some bolus. I do it (night rides) so infrequently that it's hard to remember, but I would guess I'd take perhaps 1/2 the usual dose (and I already split my dose for my evening meal, so this may only be 1/4 of the usual dose), and accept I may peak in the low/mid teens - this is similar to what I try to do for badminton in the evening.

Breakfast departures are different - I used to head off last year (for 140km+ rides) and eat breakfast (~35g CHO porridge) uncovered, which worked as long as I got out the door fairly quickly. I would end up peaking in the low to mid teens, then dropping to need to eat after ~2h30. However, this year, I have dawn phenomenon, so if I do this I end up shooting up to 20mmol/l+ which isn't ideal, and then I take 1U or 1.5U of bolus and end up dropping quite quickly (though this complete process usually takes on the order of 2h30). I can't say I've got this quite sorted, but I'm getting better at it, and I now try to take enough bolus to cover the dawn phenomenon part (i.e. the same quantity as on a normal day) and perhaps part of breakfast. This gave me a peak of 14mmol/l iirc on the last 200k ride which I thought wasn't too terrible, and then it gently dropped down into single figures.

To to summarise my thoughts regarding bolus - I try to avoid it completely except for fixing dawn phenomenon. I also try to avoid having any residual amount on board to avoid going low rapidly during the ride (I will drop anyway from basal, but I don't want it to drop through the floor which can happen with bolus IoB). I can live a bit of bolus IoB and needing to sort this out on short rides (an hour loop at lunchtime with left over from morning coffee, or my ~2h ride back home from work with some left over from lunch) but I know I will need to eat.

Having any significant amount on board is bad news IMO - I find my BG drops rapidly and I then need to eat quite a lot quite quickly to stave off/recover from a hypo, and it's then not much fun continuing to eat while you continue the ride. On my first 100 mile ride I stopped for lunch (sandwich, biscuits, coffee) and took ~3U to cover about half the total carbs. On my ride back I was eating constantly and bumping along just above hypo, wasn't much fun!

Thanks @SimonP. I’ve been afraid to eat without taking any bolus but it seems that you manage it well, relying on basal and cycling together. Plus I’m trying to maintain my time in range on an almost hourly basis right now as I get used to the condition. Perhaps I need to relax a bit if mid-teens BG doesn’t faze you, knowing it will reduce through exercise. Yesterday afternoon I did a 30 minute high intensity Zwift uncovered and drank carb drink which worked well. Unfortunately, I over-estimated bolus at tea time, dropped to 3.4 and spent the evening trying to catch up! Result was I spent a couple of hours between 10-12 mmol/l overnight. Not too concerning but shows how sensitive the balance is between BG, insulin and food intake. I’m just two months post diagnosis, returned to exercise 4 weeks ago so a lot still to learn. I really appreciate your help.

 

[SimonP]

It's very early days for you, so you also have the added difficulties of the honeymoon period to contend with, so don't worry. Experimentation is key though, even once you think you've got everything sorted, it (diabetes response) randomly changes in my experience, so you need to (re)start the experimentation, so you may as well get used to the process 🙂

You can calculate how high you may end up going without bolus, and decide if you're relaxed about that - taking 20g of carbs might drive my BG up 6mmol/l. It's not the end of the world IMO. Ideally I'd do without the transient high, but the only way to work out how to do it is to practice, so that's what I'm doing.

Having BG numbers available at all times and being able to see TIR at all times is probably not very helpful psychologically for anyone. It's very useful to have the data available but it can lead to attempts to overcontrol and to stress when the numbers aren't quite right, even if over a longer averaging period things are actually perfectly fine. Don't get me wrong, having BG data is useful and I'd not want to go back - for longer term control optimisation (i.e. basal rate and carb sensitivity fixes) as well as for shorter term control, understanding responses to specific foods and making split dosing decisions, but there's a fine line between this and attempting to overcontrol (ending up with stress about the values and annoying BG oscillations - I'm an engineer, can you tell? 🙂). I don't feel this is very helpful if you want to balance good BG control with leading a relatively normal life and doing normal things. Others may disagree, that's fine, I'm happy to discuss elsewhere, I like a good discussion 🙂

I tend to do at least a 1h ride most days for BG control purposes (though not this week due to rain and volume of work and my BG is running high because of that - I need to setup my turbo). This exercise means my BG is more stable and I run lower in general (and I get fitter too and probably accrue some other exercise health benefits as handy side effects). I sit in range during these rides without the transient highs caused by eating while riding (and the same is generally true for my commutes) or I use these short rides to fix highs rather than injecting a correction (though this is a "dangerous" thing as I sometimes don't bother to inject a correction expecting to go out soon, only to find someone books a last minute meeting so I've run high for no reason and still need to do the correction - setting up the turbo will fix this, Teams calls while riding 🙂).

Riding longer rides, which is where I tend to have the transient highs when I set off, is not essential for BG management, however I enjoy pushing the distances and seeing new things, so while I can't claim it has a diabetes-related physiological purpose it does have a quality of life purpose and I'm happy to trade off the transient high against that. There are no hard figures to calculate the cost-benefit trade-off between these psychological aspects and the bad effects of running high for a given period of time. If there were, I wonder if that would actually be better - more data to stress about 🙂

I feel I may have gone off track a little, nothing new! 🙂

 

[helli]

Most of this discussion is about what happens to your BG during exercise.
For me, managing the post exercise was as challenging - my BG could continue to drop for up to 48 hours after intensive exercise.
Depending upon the basal insulin you use, if you find your BG dropping and more hypos for a day or two after exercise, you may want to drop your basal dose. I also found that multiple days of exercise can compound this - on a 2 week hiking trip to the Himalayas (some pretty steep slopes to climb and a bit of altitude to deal with too), I ended up taking less than half my usual basal to stop the hypos.

 

[The_Bowlii]

Most of this discussion is about what happens to your BG during exercise.
For me, managing the post exercise was as challenging - my BG could continue to drop for up to 48 hours after intensive exercise.
Depending upon the basal insulin you use, if you find your BG dropping and more hypos for a day or two after exercise, you may want to drop your basal dose. I also found that multiple days of exercise can compound this - on a 2 week hiking trip to the Himalayas (some pretty steep slopes to climb and a bit of altitude to deal with too), I ended up taking less than half my usual basal to stop the hypos.

Thanks @helli. The dietician dropped my dose from 16 to 14 units recently because I was drifting down overnight. On a good night, I’m nice and flat but after exercise it often rises around midnight (whilst I’m asleep) and stays between 10-12 until 3am. By morning I’m back to normal. I do something almost every day, squash, cycling or weights so I’m basically always in a post-exercise state. It’s a minefield!