Insulin Pump & Cycling

Diamant49

I am a Type I diabetic, been on insulin for 3 years now. I did the DAPHNE course 2 years ago and my control has been good (HbA1c 6.2 - 7.0) on a standard basal-bolus regime. I am cycling more frequently now and have had a few more hypos than usual recently (mostly at weekends when I do longer rides (40-50 miles) and the day is less structured than a working day).

Anyway, at my last hospital clinic my consultant recommended that I should go onto an insulin pump - the local Trust has just purchased 120. He reckons it would give me even better control and help reduce the risk of hypos. I am waiting now for an appointment to be assessed - I might not get through this stage, since my control is good, but my consultant is very supportive so I hope it will work.

Is there anyone with experience of using pumps?
If so how have you found it on longer rides of 50-100 miles - do you turn of the basal dosage for this?
How do you wear it?

I am not entirely looking forward to being connected 24 hours a days, but I also haven't gone over 50 miles since going on insulin and I hope being on a pump will make it easier.

Lots of questions - but its a big step that I hadn't expected to be given the chance to go for and I am quite excited about.

team47b

Don't quite understand the idea of setting the insulin dose for 'normal' eating, I use a basal insulin and adjust food to match insulin, opposite to DAFNE, and take the same amount of insulin everyday and calculate carbs based on the amount of exercise I do to maintain a balance (HBA1c of 5.8%. I don't see going over 50 miles a problem on insulin.

Can't you just eat more carbs to match the insulin on longer rides to avoid hypos?

Are you considering that a pump will give you better control/lower HBA1c?

I know we are all different but I eat every 3 hours anyway and I also eat 10 grams of carbs halfway between meals or snacks when cycling this keeps my blood glucose levels fairly even and I can cycle all day without a hypo. I also eat less on the days when not riding.

Anonymous

I know all people are different but I cant see how a pump would stop hypos? At weekends or when I tend to do longer rides I know my insulin right back both my background & quick acting and then just inject later in at the end of the day when I have my main meal.

This works for me, I will try and eat some flapjack or something every 45mins-1hour during my rides but it all depends on intensity of what you are doing I guess.

Like team47b says I would try more carbs & droping your insulin down and get you body better at burning fat reserves....

Duncanandthemachine

My girlfriend has just started cycling, she's been type 1 for nearly 7 years and on a pump for most of that. She reduces her basal rate by 30-40% when riding, as per other forms of exercise and gets on grand. Check out team novo nordisk (formerly team type 1) on Facebook and twitter, they've loads of good advice for diabetics.

Oh and you can buy pouches that strap your pump to your chest to keep it out of the way.

Good luck

Diamant49

Thanks for the replies - I should have said in my original post that the hypos are not when cycling, they are usually due to (muscle?) glycogen replenishment in mid-afternoon (I normally cycle early morning). I need to be more consistent in having a small meal in the afternoon to deal with that.

Otherwise when I am cycling I do as people have advised, which is to increase my carb intake and reduce my insulin. I know what way I will react to runs of up to 50 miles, going beyond that would just require some more monitoring, along with a sensible carb intake.

I have done a little more research into pumps and there are some advantages, and some things are not as good as I had hoped. The main advantage is being able to change the basal insulin, both during exercise (as above) and to have different rates at different times of day. I am pretty sensitive to insulin, so if cycling most days my bolus level is reduced to 0.5 U insulin to 10g carbs (would be less if doing >100 miles per week - this excludes carbs taken when cycling) and I only need about 6-8 U basal - but the latter is the problem.

I really need a higher rate overnight to keep my control good and then much less in the afternoon or when cycling - a pump would allow me to set a higher overnight rate and to have lower rates in the afternoon/evening when I am particularly sensitive to insulin. The basal insulin can also be reduced or stopped completely, with almost immediate effect, as its micro-doses of quick acting insulin.

Against that, my consultant was talking about getting a pump with continuous glucose monitoring (CGM), which I hoped would mean not having to take regular blood glucose readings. However, the GCM requires a separate line to inserted, lags behind BG changes by c.15 minutes and still requires regular meter readings to calibrate - though warnings can be set if BG drops below a threshold. So it probably wouldn't do away with the need to check BG levels on longer rides.

Anyway, I have a date for assessment on 15 April, so will see what the options are then - in the meantime I hope to get a couple of 75 mile runs in over Easter, so I don't plan to be put off by having a pump or not.

team47b

If you haven't already have a look at...

http://www.shootuporputup.co.uk/

Tim and alison who run this site have a lot of good info on pumps etc, very approachable people, they will be able to answer a lot of your questions.

Just don't ask Tim about cycling or in fact any form of exercise

Diamant49

Hadn't seen that before, looks interesting - liked the diabetic idiot one. My own diabetic idiot one was christmas a year ago, after a few glasses of wine I gave myself 18U of quick acting insulin instead of 18 basal :oops: Was nearly out before I realised the mistake - but the 180g carbs I had to eat were certainly good.....

team47b

My diabetic idiot one was deciding to cycle on the main road during a hypo and being confused and not remembering that we drive on the right here :shock:

Novomix30

Quick reply, you don't need a pump to sort out your hypos, not unless you want one.
Pumps are just a method of delivering insulin, and whilst yes they are more controllable than basal-bolus insulin, as you can adjust the insulin rate and get a quick respone, they still require a motivated user to operate them. I would generally expect more testing on a pump too.

The hypos you are describing are a classic description of Late Onset Hypoglycaemia, typically occurring 2-4 hours (but variable in different people) after exercise. This is due to increased sensitivity to insulin and results in increased muscular absorption of glucose and thus a fall in blood glucose and a hypo.

There are a number of ways to deal with it, but one that I advise my patients who exercise frequently is the 10s maximal effort sprint at the end of your exercise. It has an evidence base and works most of the time.

see link - http://care.diabetesjournals.org/content/29/3/601.full.pdf

Bear in mind this has to be MAXIMAL effort, not just pretending.

I would also heartily advise you visit http://www.runsweet.com which is a fantastic resource for exercising with diabetes.

Any further advice DM me. I'm an NHS Consultant Diabetologist.