High Blood Sugar after Long Run?

Hey All! I am new to Diabetes (dxed T1 in April 2012). I am honeymooning at the moment, so I am only on Metformin and Levemir at night. I ran a race last year in the height of my symptoms and only made it 9/13 miles. This year, I wanted revenge on the race because I have a better handle on my health. My last a1c was 5.9, and things are going well. However, some of these long runs - using Gu at the hour mark - are causing me to spike after the run. I was 72 mg/dL right when my run ended, then it just proceeded to rise. Is there an explanation and possible way to prevent this? Here I think I am going to benefit from a nice stretch of lower blood sugars, but I was wrong:) Any advice would be great!

Best
Jordan Holt
Memphis, TN
Female, 26

I love the idea of "race revenge"! I had that at the Chicago Marathon last year!

I am not a huge fan of Gu unless it's a really long run as I find that I get spikes with them a lot of times. For half marathons, that's sort of my "if I'm low at the start, I'll get a Gu..." plan. I have like one in a marathon, in Chicago, they pass them out somewhere like 17 or 18 miles? I like to use more frequent "doses" of fast carbs. I usually hit the Gatorade stands at 1/2s and full marathons pretty regularly. Last year, at the Chicago marathon my CGM showed my BG running up so I had water instead for quite a bit of the race but eventually got back on track and finished around 78, right where I wanted to be since there were potato chips and beer waiting for me.

If you are pushing your pace and getting anaerobic/ sprinting at the end, that can push your bg up too.

i agree w/ AR about the anaerobic aspect. Also many of the gels on the market today are actually composed of a large chunk of complex carbs...so while they may be "quick" to take, they are not quick to enter your system b/c it takes a while to get the body to convert them to a digestible form of simple glucose.

Something else that could be happening is that there is a delayed emptying of your bowel (or rather into your bowel). So the gus you are eating are sitting in your stomach b/c your blood supply is being diverted to your muscles (more metabolically active b/c of the activity and the body says "not now stomach, I'm busy". After the run, the food is still there and stomach is still saying "do something with this stuff", and so your body lets the food empty into the GI system, and then the glucose from that 'hits' your system, causing the spike.

The other thing that could be happening is that your liver has been releasing glycogen into the blood stream to help combat a low BG (b/c of your activity, and it wants your body to have plenty of 'food' to eat at the muscles). When you stop running, your liver doesn't really get this signal, and (not knowing that your pancreas is broken so it can't release insulin to combat extra glycogen/glucose), it continues to release glycogen after the exercise has ended, causing a spike.

The first situation could be handled by not taking gus or other carbs within about 1 hour of getting done w/ exercise. This will vary from person to person, according to exercise intensity, duration, etc, so that's a vague starting point at best. However, continue to take water and/or electrolyte replacements, especially if it is hot.

The second situation could be mititgated some by sending a signal to the liver so it knows the activity is over and it can stop. I've done this in the past with a recovery shake. The large amount of fluid that enters the stomach helps to signal to the liver. Alternatively (for a more economical option w/o the protein shake stuff) is to drink a glass of milk...it's got a good carb/protein mix so it helps with recovery in a similar fashion as the protein shake, but at a much more wallet-friendly price.

In both of these cases, depending on what my ending BG is, I may bolus insulin (on top of my food bolus) to help combat this rise in BG that seems to happen (since again the pancreas is broken and can't do this, and the liver may not get the signal in a very timely fashion).

Hi Jordan,

a few thought to consider:
1) what is consumed during the run continues to metabalize after the run so be wary of what and how much you consume during the run. Gels and GU have 70-80% complex carbs (GU has 25g carbs and only 5g sugars). Experiment with other supplimentation tools that offer a higher quantity of simple carbs (Cliff Bar shot Bloks, etc...).

2) as you conditioning improves, so too does your muscle capacity to store higher quantities of glucose. As your run ends, move quickly to consume a quantity of fuel higher in protein as this will comunicate to your muscles to stop releasing glucose and begin the recovery phase.

3) depending on how hard and long you have run, sometimes an intense and long duration run can damage the muscles ability to recover muscle glycogen (see: Post-marathon Paradox in IDDM: Unchanged Insulin Sensitivity in Spite of Glycogen Depletion</a>) which show clinical evidence that intense muscle depletion causes build-up of lactid acid which causes insulin resistance within the muscle. (http://www.ncbi.nlm.nih.gov/pubmed/9113484)