Hi
@Fern Hopper , welcome to the forum.
I'll state first that I'm a T2, so what I say may not be entirely relevant to T1.
As a T1, I can confirm that everything
@Paul_ has said is true for me.
I have my usual long amount of long acting and at least 1 unit of short acting and no food.
I like to start Parkrun with a BG of less than 5. But I know by the finish (about 24 minutes as an average) I will have spiked at about 12. A slow warm down of at least another mile and a half helps a bit but usually I require more insulin to bring BG down.
There are some things I know make me rise every time (apart from food, obviously). My liver likes to dump glucose upon waking, when I visit the gym, as soon as I walk into the dentists practice, and at my annual endo appointment.
To my thinking, glucose from my liver isn't any different than glucose from food. I take insulin before eating because I know the food will raise me, this way I prevent going high.
For those few things I know my liver will add glucose to my bloodstream, I also take insulin before it does. My endo thinks it's pretty hilarious and somewhat unnerving I dose for seeing her just like I would for lunch.
But it's much easier for me to prevent those highs than to correct them afterwards, and it saves me from feeling rubbish and frustrated.
Mind, there are situations where I rise without food in an unpredictable way, and of course I can't dose for them, but I can for things that have proven to cause a predictable rise for me.
I only wish my liver dumps came with a carb count, the amount of insulin I need varies a bit, like Paul_ suspected. Trial, error, and gut feeling are my guides on this. Especially the gut feeling part, if it tells me to take a bit more or less insulin than logic tells me, I tend to go with the gut feeling, it's often correct.
I don't run, but I'm still trying to find a way to go to the gym (rise), followed by a short cold swim (steep drop). I'd want to dose for the gym, but this means the insulin will be most active during my swim, so a bad idea.
How often do you do those runs and for how long have you been doing them?
When I started going to the gym last summer, my spikes were much higher, apparently my body is getting used to this weekly torture.
And equally, when I started open water swimming in October, the drop was much more spectacular than it is now I'm used to going in at least twice a week.
So things may improve all by itself if you're lucky!
And well done on doing those park runs, I couldn't do them if my life depended on it, and I'm twenty years your junior!
I'm with you on the tight control and the hba1c range though, if not on the BMI at 35.
One of the downsides of tight control is feeling rubbish at relatively low numbers, starting at below 10 for me.