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Dropping too low when cycling home

Sgathach

Well-Known Member
Messages
75
Type of diabetes
LADA
Treatment type
Insulin
Hi everyone,

I'm having some issues with my blood sugar during exercise, in this case cycling. I started cycling to and from work, about 40-45min and I'm not a pro cycler, so fairly slow.
In the morning, I take my lantus, around 5 units atm, and a banana and I'm good to go. I spike to about 8.1/8.2 briefly but by the time I get to work am down to around 5.5/5.6, all good.
During the day I eat low carb and been mainly hovering between 5.5 and 6.6 after lunch and back down.

However, most of the week now I struggle to get home on the bike.
First time I ate a banana a bit late, about 15min before i cycled, so I dropped from around 6.6 to 3.8 by the time I got home.
Next time i ate the banana earlier, about 30mins before -same result, had to stop and take some glucose tablets too as I was around 4.7 and still far from home.
The other thing is, once I get home, I usually eat some carbs and go to training, but due to corona, the dojang is closed. So I wanted to get home, eat and do my own workout but the carbs just don't seem to catch up till almost 2h later? I guess in normal training we do the right amount of intensive bursts and normal cardio that it doesn't drop me quickly, but last time i went walking to a bit of a secluded training area outside (barely 15min) and sugars fell so quickly, from around 7.5 down to 5.5 and since it was dark by then i didn't want to be alone and hope sugars catch up, so had to ho home. It wasn't until again almost 2h after the meal that my levels started to rise.

I really want to be able to work out and i thought normally, 5.5 is the ideal level to be at but I feel i cant do anything as I'm dropping so quickly as soon as I go walking or anything.

Today I'm experimenting with eating a 14g carb chocolate brownie and 17g choco almond milk 2h before cycling and a small carton of chocolate milk about 30mins before i cycle and hope I can get home safely this time.
And that I don't need a long time to top up more carbs to exercise more after.

Any insights would be hugely appreciated, I want to do a lot more but I just can't seem to get the level safe enough and I've started to put on weight too, so more of a workout is really needed - and even if the choco milk works, that's not the healthiest or best way calories-wise to see that I can cycle home.

Thank you.
 
You my have covered it depending on how you go today.

I cycle alot. I was out on Wednesday and I did 46 miles

Before heading out I eat things like grenola bars and intake some sugars.
I stop every hour to check bloods and usually I'm heading low.
Throughout my ride I just take on jelly babies. I have one every 20-30 mins, when I stop I have a little bit of a cereal bar and an energy shot

It's all about trial and error. You cycle one way then the other, is it down hill on the way then up on the way back. Conditions always effect things more. I find breezy conditions are my biggest issue as you work harder.
Also what type of job do you do, is it active as this may also class as a workout and have an effect later in the day

I'm heading out this morning so all I do is not take my levemire and I don't have any novarapid with my breakfast.
 
I'm a teacher but this week we had no kids in so I was basically just sitting.
I was up at 8.7 at my usual time to finish work but a meeting went on for another 20minutes so I started cycling at 7.6 and 45 min later as I got home I was at 3.8. I did take 2 glucose tablets as I still had to walk uphill home.

So, jelly babies may be worth trying. What is your level when you start cycling? I just feel I'm dropping so fast, my only insulin atm is Lantus at 8am, but the cycling issue is around 5.30-6.30pm.

Uploaded a screen shot, I started cycling just before 6pm.
 

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Hi,
Hope today goes better for you! Are you also injecting any bolus insulin with lunch which might still be active when you're cycling home? It might also be worth lowering your morning basal a bit to see if this helps? My DSN is always an advocate of trying not to 'feed' exercise with snacks but instead lowering basal insulin (ideally before exercise, if you can plan that far ahead!). I'm on levemir twice a day so I appreciate this is a lot easier for me, as I just amend my morning dose if I'm planning more exercise that day. I also take quite low amounts of insulin so have a pen which does half units. I got one from my DSN then one from the GP on prescription (novopen echo). Hope you have a more relaxed cycle today!
 
Thank you, I don't have any bolus insulin, only Lantus in the morning and I only took 4 units this morning too, usually 5 or 6.
I know during honeymoon insulin production can go up and down, I'm really wondering if i should lower the dose even further and stay low carb and see.
I really want to work out a lot more and a lot longer and I hoped cycling may help me lose a bit more weight too - but not if I need to eat as much all the time ....complicated.

I'm also really surprised by the super quick drop, that's easily 70 points in 45min and that's not exactly speed cycling and only the last part is uphill and i walk that mostly....odd
 

Hi there, well I know we cannot tell you what to do medicinally BUT I had the exact same issue when first diagnosed. I was already an exerciser but became fed up when I had to keep eating snacks that I didn't want just to prevent hypos. My Consultant said generally speaking, if you are having to keep your glucose levels up by eating then you are taking too much insulin. I reduced my insulin to very low levels (they had been 10 units of Lantus and around 1 to 2 units of Novarapid per meal as I was also low carb). I was (and still am) in the honeymoon period and now am on 6 Lantus and novarapid if and when I need it. Although you are only on 4 units, you may find even that needs to be lowered. Keep testing. x
 
Thank you, yes I think you may be right, my endo did mention that I can adjust doses.
I was fine for a while on 5 units and 3h a day training, no cycling.
Then without work or training and only home training I needed 8 units to keep level. I don't work out that much at home but I guess cycling is a new enough exercise for me that it taxes my body enough to soak up extra glucose or something.
This weekend I have no cycling planned so I will observe how it goes and if I stay in good range I may reduce my dose for monday more if I want to cycle.
On monday I can possibly also phone the endo to get advise as my appointment isn't till May.

Just seems silly if I need to eat stuff that shoots me to 10 just to maybe make it home and then I miss the timing and all that was for nought anyway - frustrating.

Luckily got the cgm and that helps a ton. so I can experiment and stay safe too.
 

Hi there, just be aware if not already, when you adjust your basal dose it can take a day or two to have an effect and it's more for an ongoing effect so it's not really something that you would adjust say for one day to cycle, and then back up the next. In other words, it's not for using like novarapid for example, ie, one meal equals so many units. Hope that makes sense. x
 
Very strange how quick it drops. I can see you go high then jusy shoot down.

I do tend to find it can drop quickly. Like I say it normally depends on distance and how hard you cycle
It could be to do with your morning lantus but I wouldn't know 100%

This is my day today on the bike
I had 2 slices of toast with peanut butter on and a small bowl of porridge. I had these at 9 then went out at 10
I cycled 50 miles today and took in 2 big hills of around 900m ascent between them

I had a jelly babie every half hour and stopped for high 5 gels and carb bars after around 20 miles and 40 miles so you can see the little spikes but I still came down quickly
I got home at 2 and was down to 4.1

I think I'm going to skip my night time levemire next time I go out aswell as the morning one so Iv not had any in my system for 24 hours
 

Hi Mark, hope you don't mind me asking but what type do you have? I'm type 1 and aware I produce as good as no insulin, so have always been extremely strongly deterred from skipping insulin doses completely from diabetic nurses/consultants.

We know exercise makes you more sensitive to the insulin action, so I've always tried to gradually increase exercise if I've had a break from it, or want to increase what I'm doing. If you're suddenly doing a one off amount of exercise greater than the usual amount, I can understand greatly reducing insulin doses of course. Sounds like an impressive cycle today!

I have also been warned not to skip injecting too frequently, as the insulin is obviously needed to transfer glucose from the blood to your glycogen backup stores, so could increase hypo chances and extend recovery time in future.

It's very frustrating if you're already on low insulin amounts and don't want to have to eat just so you can exercise! Annoyingly it also takes a few days to level out a change in basal dose, I think they recommend trying changed doses for 2-4 days to check the effect. You might find you need different basal doses at the weekend compared to when you're cycling to work? Hope you're at least enjoying the cycle!
 
Good luck with the experimentation! i would agree that you need to play with the dose and not snack so as to protect your insulin cells that remain and to avoid unwanted gain.
Leisurely cycling or walking do tend to drop you lower than higher intensity bursts or weight training so if there's any way to change the order of training that may help but th emain thing will be the basal dose.
I always recommend Adam Brown's book Bright Spots and Landmines (Diabrribe for free or Amazon) because he is a keen cyclist and provides some useful ways to think about managing blood sugars during exercise. He is a low carber too.
 
Thank you for this, your eating scheme makes sense and you cycle huge distances, but I just checked mine and one way from work to home is about 5.7/5.8 miles...and I take about 45min for that, so it isnt a huge distance or at any great intensity. Im3not used to cycling much, I usually do martial arts, but I had never noticed that it would be this exhausting - I do feel tired at home and a bit shaky but mainly due to being super low not because cycling is killing me - so I'm really surprised how quick I'm responding.

Actually the big spike in my chart just before cycling around 3pm also came down quickly - I had trialled a brownie first, got spiked right up to 10, I did 5 minutes walking up and down stairs in the hallway (literally 5min, maybe 8 flights of stairs just up and down) and it also caused a very quick drop even after I sat down.

I'm aware Lantus isn't to be adjusted as a bolus would be, but if I'm dropping so quickly even after a rise to 10, it must be due to too much insulin, even if it was a low dose? Or does a tiny amount of exercise really do that?

At home I ate low carb and relaxed for about 2.5h and after that I did a 2h home workout with yoga, push ups, kicks, small weights etc and I stayed fairly level between 5 to 5.8 the whole workout, so no huge drops or anything then. I did have 3 jellys before I started the workout but if they did anything I'd have expected a bigger spike and bigger drop after.

Bright spots and landmines is a great book, also My Diabetes Science experiment is amazing. Now I've stsrted Diabetes Handbook for Athletes too.

The thing is, like @UK T1 said, it's tough if you are on a low amount of insulin, you only take basal as it is and need that to last all day but then still be ok to exercise.
Sadly I cant change the order of training, cycling wasn't even meant to be training, I just wanted to get to work without the subway and I just want to cycle home safely without risk a hypo. For any other exercise I seem to stay level enough but something about cycling....or sometimes about cycling in the afternoon, I guess in the morning Dawn phenomenon helps me carry it through without issues.

I will try reduce the dose further and see what happens, but it's very odd, I mean if I go from 4 to 2 units, I'm barely on any insulin then. I mean that's a good thing but really odd for a T1 diagnosis, no?
It can possibly be due to cycling being new to me and it may change when I adapt as well.

All your comments have been super helpful, thank you.
 
The exercise increases your insulin sensitivity for quite a while. In my case to the next day. So you'll need less insulin.

You may need to reduce your background dose - if you're on long- and short-acting.

You'll also need less insulin for carbohydrate.
 
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