Skip to content

Type 1 Diabetes and Endurance Sports

Hi there,

I am a Type 1 diabetic diagnosed at 33 years. I am now 42.

Exercise used to be such a big part of my life, including mountain biking and gym. Recently I had an incident with low blood sugar.

I don’t have any self belief in starting to practice again as this happened during practice. My sugar levels seem to be very sensitive when exercising: for example, I did a normal 20 minute treadmill walk and run. Before this my sugar level was 13 and after it was 7.5mmol/l.

What is a safe sugar level to have when mountain biking? When is the best time to practice? And what is the best food to eat during, for example, a 40km race to maintain sugar levels?

Will I as a Type 1 diabetic be able to do endurance races like JHB to Sea?

Thanks for making it easier to live with diabetes.



What to read next
Join South Africans with Diabetes on Facebook

Join our diabetes community


  1. Leon Grobler Leon Grobler

    Don’t be discouraged, I was diagnosed as a diabetic Type 1 at the age of 48. Am now 56. I have maintained a consistent level of fitness throughout my life and am of the belief that I already had diabetes without knowing it- this as a result of my fitness. I too , like you, enjoy mountain biking and road riding, and have at times found it challenging to control my sugars. However, I would encourage the use of low GI foods whilst on the ride, such as brown bread rolls with peanut butter and cheese, water and 32Gi ENDURE low GI drink (available from Dischem). At least 2 hours before the event I have a light breakfast of a slice of brown toast with peanut butter and a cup of tea or coffee. I still find training early morning the best time to exercise.
    I have participated in and completed Sani2C, Imani Wild Ride (4day event), Berg n’ Bush Descent, and more recently the Hill2Hill, amongst other events.
    Ensure that you are taking the correct dosage of Slow Acting insulin at night.

  2. Guy Meredith Guy Meredith

    Hi Danie. I have been a Type 1 diabetic for 44 years. In that time I have run 3 80km Puffer trail runs, 11 Two Oceans marathon, 10 3 Peaks and numerous other ultra runs. You can certainly exercise with Type 1 and you can definitely do endurance events. The key for me is to test frequently (usually every hour, which I realise can be inconvenient when cycling but it is better than having a low). I typically run with Super C sweets, and just have one every now and again if my blood sugar drops. I am also on Dr. Bernstein’s low carb diet and eat only 30g of carbohydrates per day, which is an excellent method of control as you very seldom have serious lows, because you take far less insulin than when you eat carbs. So, you could try this approach too. I don’t know if this will help, but don’t stop your training whatever you do – it helps keep your blood sugar under control and is also heaps of fun – and it is also great when you can beat many of your non-diabetic friends!

  3. larry dolley larry dolley

    Ihave done 20 Argus Tours, 20 years of squash and now am diabetic. I stopped cycling 3 years ago and do not know whether I was diabetic during my fitness days – highly likely though.
    I want to go fit again at 59 but am confused about sugar control where I am on metformin. Only sugar highs but no lows.


What do you think?

Sweet Life is a registered NPO/PBO (220-984) with a single goal: to improve diabetes in South Africa. We are funded by sponsorships and donations from aligned companies and organisations who believe in our work. We only share information that we believe benefits our community. While some of this information is linked to specific brands, it is not an official endorsement of that brand. We believe in empowering people with diabetes to make the best decisions they can, to live a healthy, happy life with diabetes.