By Russel Cobb
I have had Type 1 Diabetes now for nearly twenty years and, despite this, believe I am fitter now than I have ever been as a result of running. I typically run between 10 and 20 miles a week and this year will run three or four half marathons.
Starting Running
I started three years ago when I was approaching 16st and realised something had to change…A friend helped me work up a program. He was very clear that to make any difference I needed to exercise for a minimum of three times a week, for at least twenty minutes and that I should get a heart rate monitor to measure that I was exercising at the right level.
I am a big fan of the heart rate monitor as it ensures that you don’t overdo it to start with. I am convinced that many people think they must make a big impact at the start of their exercise program and go for a decent first run that leaves their muscles hurting the following day…requires a day off and then the next run hurts even more! By using a monitor you can get into it gently…by walking or run/walking if’s a sustainable way of getting going…and I still use it for every run.


It is key to have an outcome goal for your exercise... What do you want to happen as a result? Lose weight…feel fitter...complete an event...achieve a level of performance? Improve your blood sugars…Or something else…?
If you have a goal then it helps you keep exercising. Mine is to keep my weight down and feel fit. This has allowed me now to go no more than a week at any time over the last three years without running and most weeks to run three to four times. I even surprised myself by running three times a week before work (which requires getting up at 6am!!) so I can spend more time with my family in the evenings.

Pumped up Running!
heart rate monitor
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I have now had an insulin pump for 10 months and have really appreciated the flexibility it brings, especially to exercising. The pump works by continuously drip feeding a basal level of insulin and enables bolus insulin on demand using a few clicks of a button. No more injections just a new canular (small plastic tube inserted using a needle to deliver insulin under skin) every three days. The benefits are ability to give insulin very discretely (looks like texting!), gentler low blood sugars and the ability to flex insulin up or down quickly and easily whether deciding to exercise or eat on the spur of the moment.
How does it help running?
The pump is very flexible. If going for a short run (under 45 mins) then I tend to disconnect and then correct basal delivery on my return. If going for a longer run I temporarily reduce the basal delivery depending on mileage. Very simple to do, few clicks and you tell it to reduce normal rate by any percentage between 0 and 100 – generally further mileage greater reduction.
The pump also has a continuous glucose monitoring capability. This requires a second canular to be inserted (these are not funded and they are expensive!). This sends the pump a continuous blood sugar estimate. This is great for longer runs, as whilst not as accurate as blood sugar meter, it shows you how your blood sugar is trending, so whilst out you can look at the screen, feel confident and focus on your running!
Pump Screen showing blood sugar estimate and trend
Personal Best!
I recently ran the Silverstone Half marathon in a personal best of 1.37.06 with pump and continuous blood glucose monitoring attached! I started with a blood sugar of 6 mmol, reduced my basal to 25% of normal, ate a Mars Bar and drank a bottle of Powerade ( approx 70g of carbohydrate) and set off! The pump screen showed a gradual rise in blood sugar up to approx 11 mmol after 3 miles when it stabilised at this level for about 2 miles and then started to come down. At 10 miles it was at 7mmol and falling so at this point took a couple of Go-Gels (approx 50g) and finished with a 5.6mmol.
I was delighted to break 1.40, for the first time, and strongly believe that part of this was enabled by feeling more in control, which meant I could focus on my performance rather than worrying about what my blood sugar was doing!
Overall I am delighted to have a pump. Once you get the hang of it, it really helps with control and it is great not having to inject and worries about being permanently “attached” and sleeping with it proved not to be issues and from a running point of view brilliant!
Russell Cobb
May 2008


By Ben Buchanon
Having been diabetic for 11 years. I have opted for short-acting insulin before meals, combined with long-acting overnight, for most of that time. I appreciate the flexibility of activities, timing and food-types that this regime allows me. It means I fit my diabetes around my life rather than vice-versa. It also allows the opportunity to exercise in a variety of ways without diabetes presenting anything more than a consideration.

My typical insulin requirements are:
Day time (Humalog):
Breakfast (apple & banana): 2-4u
Lunch (sandwich & crisps): 4u
Dinner (pasta/curry/roast): 8-14u
If I have a pudding, or a particularly large portion for dinner my dosage may increase by up to 50%.
Night time (Humulin I*):
after a typical day of moderate activity: 18-24u
*from time to time I take a small dose of Humalog as well, if my blood sugar is a bit high ie greater than 9 mmol/l.
Height: 6’2”, weight: 14st 8 lb
My preferred form of exercise is running, although I also enjoy cycling. In either case the major concern as a diabetic is the endurance factor – maintaining blood-glucose at a safe level, and an adequate level for my energy requirements. The following is with reference to running; as a rule I find the energy demands from running are up to 50 % greater than with cycling.
As a simple rule I undertake 3 kinds of running:

a) short runs (4-8 times a month)

b) long training runs (1-3 times a month)

c) very long (event) runs – these are rare

In all cases above I try to avoid running less than 2-3 hours after taking insulin, so that ‘insulin uptake efficiency’ is not a complicating factor.

a) Lasting 20-45 minutes I will generally run quite quickly (for me! – 8 to 9 minute miles), often off-road and over hilly terrain. Typically I do not find that over the exercise period low blood sugar is a concern. Preparation will consist of a check to ensure my blood sugar is between 7-10 mmol/l, and consumption of a Mars Bar or approximately 200-250 ml Lucozade. For blood sugars outside of that range I will adjust my initial glucose intake accordingly, by up to +/- 100%. Although I take ‘emergency’ glucose tablets with me, they are rarely needed. Upon return my blood sugar is normally 5-9 mmol/l and the ‘honeymoon’ effect of exercise on my blood sugars will last for 8-12 hours afterwards, meaning I reduce insulin dosage by up to 50%, or eat up to 50% more.

b) Long training runs would generally be 1 hour – 1hour 50 minutes. I would typically run more slowly, at about 10 minute mile pace. Preparation is as for short runs, but hydration and re-stocking with glucose are further considerations. I have tried drinking orange juice and water (50/50) en route which provides excellent salt and water replenishment, but generally needs to be supplemented with a couple of glucose tablets every 20 minutes. Alternatively a brief stop after an hour or so and a (330ml?) pouch of a proprietary energy drink will suffice. Frequently after such a run the ‘honeymoon’ effect will last for up to 24 hours (in a diminishing capacity) and for even a substantial meal such as a baguette and crisps I may not take any insulin at all if eating within a couple of hours of return. Night time insulin requirements will generally be reduced by up 50 %.

c) I have run a couple of half marathons and a full marathon. For such distances, preparation and management are the same as above, but it is imperative to maintain hydration and fuel intake for the duration. Hydration is essential and I plan to experiment with adding sugar to my orange juice / water mix for a single source of hydration and fuel. Experience so far is based upon simply extending my management for longer runs, but in practice I find the body ‘settles’ after an hour or so and while I think hydration needs decrease as I sweat less, digestion can become harder. Experiences of having drunk too much lead me to believe that over an hour, little and often is the best approach for hydration; fuelling requirements remain the same. Potentially a greater factor than the distance covered, is the time on your feet. I completed the London Marathon in 5 hours 18 minutes – no records broken then! But I was running all the way and on my feet for all that time. My body went way past anything it had experienced before and ‘hit the wall’ at about 3 ½ hours. Little can be done to address this, what a diabetic can do is ensure that diabetes doesn’t further complicate matters. Following the management outlined above, my blood sugar level after the marathon was 11 mmol/l – about right for endurance sport in my view.

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