How can somebody with Type I diabetes keep blood sugar levels acceptable during and after a multi-hour ride? I recently upgraded my bike to a Merckx EMX1 and started doing some serious riding.  I am riding 50&ndash;70km(30&ndash;45 miles once a week usually including a second cat climb and sometimes one or two 3rd and 4th cat climbs.  I have read through some of the nutrition questions and although the answers and suggestion apply in a general sense.  I have more often than not had problems of super high blood glucose after a ride, not problems with hypoglycemia.  This is because I am very worried about have a hypo while on a long ride.  I would be stuck far away from my car or possibly anywhere where I could get the instant help I need.  I am also usually alone (though I am looking to get involved with a group ride).

I am looking for some help and advice on how to effectively eat before during and after a ride.  I usually stop half way through and test my sugars to make sure I am ok and see if I need to add more food.  I don't usually drink electrolytes but I make sure to stay well hydrated.  I carry nutrition bars and energy gels on my rides, usually way more than I need.

I do this excercise to stay fit and to lose weight.  I am 185cm (6ft 1") tall and 87.5KG (193 lbs), I would like to get down to around 80kg (176 lbs).

My question is really how can I eat and take insulin effectively avoiding high and low blood sugar whilst making sure I am not eating too much that I have no net weight loss.
I too am a type one diabetic and I understand your concerns, how ever I might have some suggestions to help with your problem. I always make sure to carry a Camelbak pack with me to enure I have my Glucometer and other supplies along. I check my sugars before I start the ride, if possible I might have a little extra food at the time, just to get me started. 

I also make sure to carry along some chocolate bars if my sugars get low. I find Oh Henry or Mars Bars to be good, since they have various types of sugar in them and they also have peanuts to help sustain the glucose intake. In addition to the sugar I bring along, I also bring protein bars since those have carbs in them, but also a lot of protein to help release the glucose in to your system slowly. 

The name brand or protein bars I use is called "Clif Builders" and you can get them at Costco in Canada, hopefully you could get them in your area as well or a similar product, the important thing is that the protein bars release the carbs slowly. 

I also drop each of my insulin dosages by 2 units on my morning dose and sometimes my evening dose also gets adjusted because after a long ride your body continues to burn sugar at an accelerated rate. 

This helps me not need to overeat, the high problem of high sugars after a ride is due to over compensating for the amount you fuel being burnt on the ride and most important of all at least until you get to know you routes really well and what you truly need for food intake, make sure to check your blood sugars on the ride before you eat and on a regular basis and bring along extra protein and chocolate bars, they don't take up much space and the Camelbak will have lots of room for them. Remember the Chocolate bars are only for when your sugars get low, otherwise stick to the protein bars. 

You will also find your rides will be better and more energetic if your sugars are in the nominal range. The other advantage to lowering your dosage on riding days, is that it will help you lean down. It doesn't help you at all if you have to overeat to keep your sugars at a normal level, but if you lower your dosage and understand that the bike riding it self will lower your sugars to a degree it will make it easier, it really is about knowing your body how it burns sugar and how to balance it all on days you ride.

P.S. My longest ride so far was 55Kms and I found by dropping my morning dosage, it helped me out in not battling the insulin to keep my sugars up at a normal level. Perhaps if you are going on a longer ride you might need to lower your dosage another unit or two, don't make huge changes in dosages until you know your insulin needs. 2 units less is quite safe and make sure even if you lower your dosage to bring plenty of food along.

I hope you find this information helpful, enjoy the rides.