Hi, first time posting ... I was actually diagnosed Type 1 in 2011 and have been successfully managing with insulin (novorapid/levemir). I recently started playing tennis and have found that if I eat beforehand and have taken insulin, when I play tennis (even two hours or so after) my levels will drop considerably even if I've taken a lower dose of insulin than needed. So I tried not eating and not taking insulin as usually when I do this my levels will stay constant but for some reason my levels are increasing rather than staying level or even going down which I might have expected with lots of running around! Does anyone have the same problem or any advice?
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Exercise and levels
- Thread starter beabso
- Start Date
SimonP78
Well-Known Member
How long do you play for?
The rise you see without any insulin (I assume you have some basal insulin on board though!) is your liver being helpful and providing you with some glucose. Depending on how energetic you are (aerobic exercise produces less or no initial rise compared to a definite rise caused by anaerobic exercise) and how long you play for (there is only a finite amount of glycogen in the liver, though probably more than enough for a set or two of tennis I fear) you will get different effects.
I play badminton in the evening once a week, I take half my bolus for supper (and supper itself!) before I head out to play, I may initially head high, but I then tend to head low towards the end of an 1h30 session, so have a snack at that point. When I used to play during the day I'd probably have some residual bolus on board and would typically need to have a snack beforehand or during.
If you're playing 2h after eating, I'd be tempted to take your normal bolus for the meal (to avoid going high afterwards) then have a decent pre-game snack (20g+ uncovered) and some other odds and ends to eat as you play as needed.
The rise you see without any insulin (I assume you have some basal insulin on board though!) is your liver being helpful and providing you with some glucose. Depending on how energetic you are (aerobic exercise produces less or no initial rise compared to a definite rise caused by anaerobic exercise) and how long you play for (there is only a finite amount of glycogen in the liver, though probably more than enough for a set or two of tennis I fear) you will get different effects.
I play badminton in the evening once a week, I take half my bolus for supper (and supper itself!) before I head out to play, I may initially head high, but I then tend to head low towards the end of an 1h30 session, so have a snack at that point. When I used to play during the day I'd probably have some residual bolus on board and would typically need to have a snack beforehand or during.
If you're playing 2h after eating, I'd be tempted to take your normal bolus for the meal (to avoid going high afterwards) then have a decent pre-game snack (20g+ uncovered) and some other odds and ends to eat as you play as needed.
Many thanks for the explanation which will help me to understand what's going on. I will definitely try eating with half bolus before I play and see what happens. I play two or three times a week (1 - 2 hrs) at different times of the day and this also seems to affect how my levels react. Like most issues I've had with managing my diabetes, I've learnt that everyone is different so what works for one person, doesn't for another. That said, it's always great to hear other's experiences and to know that you're not the only person struggling to make sense of it all. Even after 13 years, I still get surprised/confused by some of my readings! At the end of the day, I am so grateful I have a Dexcom sensor which makes monitoring levels and dealing with highs and lows so much easier.
SimonP78
Well-Known Member
Yes don't worry you're not alone in getting confusing readings and things changing depending on when you play (and which way the wind is blowing it sometimes seems). Certainly insulin sensitivity varies across the day which can have a large effect on me, equally if you have some particularly energetic games (or not) in a given session this changes things. All part of the fun 
