Swimming

Why does it have to be so difficult? Not swimming in itself, but the part about managing the BG.

From I was 6 years old, I have been swimming once a week. Just for fun and exercise, never competition-minded (except for the personal competition you would have with yourself :-)). I continued this routine until I moved to Odense 6 years ago. When I began my university studies, I even went swimming twice a week sometimes. This was because I would sometimes use an hour in between classes to go swimming with some of my fellow students. There are swimming facilities at the university, and they are of course used by the sport students, but the “holes” in the timetable are free for other students, as well as employees, to use.

Those of you having read my blog from the beginning – or at least the recent post of January 16 – will probably, with some quick mental calculation, have realized that the D was introduced during the years that I have been practicing swimming. Besides the swims at the university, we would always go swimming on Saturday afternoons, usually shortly after lunch. Only once did this routine cause me a severe low afterwards. I could have slightly lower sugars (2.5-3.5 [45-63]), but never really posing any problems, except for that single one some 13 years ago.

The last couple of years I haven’t gone swimming. There is really no good excuse for that, just plain laziness in working it into my lab-routine. I took it up again in the fall, though. This time, being on the pump in stead of injections, I thought a lot about how to tackle this workout. The time in the swimming facilities specifically allotted for employees at the university is Fridays 12:00-1:00 PM. Being a bit annoyed with the time being just around the time where I will usually eat my lunch, I decided that I would work it in anyway.

My initial approach was similar to the one I used for soccer practice in the spring, where I would also disconnect my pump during the activity. I worked a lot with the timing of the snack and the amount of insulin to cover it before going swimming. However, only once have I succeeded in avoiding a low afterwards, despite the fact that I, of course, copied my approach from this successful day to the following Fridays. I have a goal of 30 laps (40 m each), or 24 laps (50 m each) when the pool is not split in two, within approximately 35 minutes. I have only fulfilled my goal a couple of times so far, because usually I will begin feeling this special fatigue and missing coordination in my motion, clearly telling me that I am low, at about 24-26 short or 20-22 long laps. I leave the pool, shower and get dressed, and usually get a reading of 2.5-3.5 (45-63). That I can handle without a problem. Sometimes I don’t even bother to chew more than a couple of glucose tabs (which is about half the amount that I will actually need to correct this if only treating with glucose tabs), while walking back to the lab (approximately 600 m) to get my lunch.

Since being on the pump I have had a fare greater share of readings below 2.0 (36) than I ever had with MDI. I believe the lowest reading after swimming have been 1.8 (32) or so. Until last week, that is.

Last Friday the pool was divided into two, and thus my goal was 30 laps. I had reduced my basal to 60 % a couple of hours before, and at 10:30 AM I had a snack of ½ slice of rye bread, a banana, and a few M&M’s. I bloused conservatively for this, using a combined bolus where a fraction of the bolus (0.3 U or so) was delivered during the course of an hour. Before heading for the swimming facilities I tested 6.9 (124), which I thought would be okay as I knew I would be disconnected from the pump for approximately 1 hour. However, once again I felt a low creeping up on me when I reached 26 laps. The symptoms weren’t too bad and I actually debated a little with myself, whether I would do 2-4 more laps before stopping. I didn’t though. I capitulated and headed for the shower. I didn’t feel too bad so I didn’t head for my locker right away to test and correct. I remember some music being turned on and one of a technician, who sometimes comes to perform experiments in our lab and whom I occasionally run into in the swimming facility, commenting on it, but I wasn’t really listening. Once I was dressed and sat down to test I got a reading of 1.2 (22). Damn! Just seeing such a reading automatically can make me feel bad. I was able to treat it myself, but I must admit that I felt a bit run-over when I made my way back to the lab to get my lunch. It scares me that sometimes I am apparently capable of functioning quite normally despite such a dangerously low BG. It also makes me seriously consider getting a medical ID that I can wear when going swimming too (I know, I know, I should wear one at all times, but the truth is that I never really have. I have a talisman-type ID, but never wear it because I am annoyed with it. It swings too much around my neck if I move just a little faster than slow walking, and I cannot tolerate that).

This scary post-swimming low was one of the things that I discussed with my favourite nurse, Alice, at my appointment with her this past Thursday. She suggested that I simply turned off the pump/set the temp basal to 0 % an hour or more before going swimming, as she believed that not only the swimming, but also my morning bike ride getting to work, is affecting my BG during this 30 min swimming work out. Also, to prevent those significant drops in BG that I still tend to see in the late afternoons around my bike ride going back home from work, she encouraged me to try to turn the pump of approximately 1 hour before my anticipated departure from work.

I set out to try this the following day. At 10:15 AM I set a temp basal to 0 % for 90 minutes, while getting my snack and a conservative bolus. I was busy in lab the whole morning, and just did a quick test before hurrying towards the swimming facility at 11:45 AM. I was 9.7 (175), and though about whether that was actually a little too high. I didn’t do anything about it though, just headed for the pool. This time the pool wasn’t split in two, so I was doing 50 m laps. I felt full of energy. Passing the 20 laps I began feeling a little tired, so I decided to end my session with just 2 more laps of slow, cooling down breast swimming. In the shower I ran into one of the technicians from our lab. We talked a bit, and I told her (she had heard the story of my scary low the Friday before, as I told the other technician about it one morning in the lab, where she told me that the music was folks music for a special team occupying the pool after us) that I felt a lot better today. I actually expected that I would be in the high 3’s (63-70) afterwards, but as you can see from my chart below, I wasn’t. 2.8 (50) was all it could be.

Why does it have to be so difficult to figure this out? Anybody have some experience with swimming and pumping that they would like to share with me? I would like to make it work, and even if I don’t, I am not the type to give up because that would that I let the D rule my decisions in this matter. Only I don’t want to risk going completely sugar cold because of my stubbornness, so inputs are more than welcome to help change this pattern of lows caused by swimming :-)