Updated 25 November 2013

How to exercise as a diabetic

Exercising as a diabetic can be tricky. We spoke to Crossfit coach, Mark Koekemoer, a type 1 diabetic, about how he trains and what advice he has for other diabetics.


Mark Koekemoer (32) was diagnosed with type 1 diabetes at age 15. Type 1 diabetics cannot make their own insulin, and to keep functioning they have to either use an insulin pump or injections.  Yet despite his condition, Mark is a CrossFit coach at Cape CrossFit where he trains and regularly takes part in athletic competitions.

Anyone who knows anything about diabetes will probably be surprised at this intense level of exercise given his diabetes. But according to Mark his regular vigorous exercise, coupled with a ‘clean’ diet is what’s key to managing his condition.

“You can’t really ever ‘control’ diabetes – every day is different. But good management means having good blood glucose levels, which I manage with insulin injections, the right food, and exercise. It's also important to have a good attitude, otherwise this disease will get you down,” he says.

Diabetes  is a disorder of carbohydrate metabolism. In type 1 diabetes, the pancreas cannot produce the hormone insulin. Insulin is produced by the beta cells of the pancreas which is secreted in response to an increased concentration of glucose in the blood and is vital in controlling blood glucose levels. A person with diabetes cannot control their blood glucose and they become hyperglycaemic – meaning that they have abnormally high levels of glucose in the blood.

Mark believes exercise is vital for managing glucose levels, as it makes the body more sensitive to insulin. This in turn means he can eat the same amount of food and use less insulin. “It's a little more tricky than just doing exercise, though,” he adds.

Different types of exercise

 “I've always been very active and in my experience I found that different types of exercise affect my blood sugars differently. Anaerobic sports – short bursts, high intensity – such as lifting weights and sprinting raise my sugar levels. While aerobic sports – longer duration, low intensity – will quickly lower my levels. There are other contributing factors, but that's generally the effects that different sporting activities have on blood sugar.”

In order to keep a check on his glucose levels during his workouts, Mark tests himself regularly.

“As a diabetic my body cannot respond to high or low glucose levels very well due to lack of insulin, so I need to pretty much manage it by regularly checking my levels and either taking glucose to raise it, or insulin to lower it. I've experimented quite a bit, and this has given me some guidelines on what to do before, during and after exercise. 

“Different types of exercise have different affects. If I don't have enough insulin on board before I go into a CrossFit workout for example, my glucose level will tend to skyrocket, and I will be very weak during the workout. However, if I head for a climb up Table Mountain and don't eat a banana before I go, my sugar will probably go very low and I will need to take a break to recover from hypoglycaemia.”

Research has also shown that people with type 1 diabetes may have better blood sugar control during workouts if they lift weights before cardio exercise. In the study researchers interrupted participants if their blood sugar fell below 4.5 mmol/L and got them to eat a snack.

When they did aerobic exercise first, their blood sugar dropped closer to that threshold and remained lower for the duration of the workout than when they lifted weights first and ran second.

Lifting weights first was also associated with less severe drops in blood sugar hours after exercise, and post-exercise drops that did occur tended to last a shorter period of time. In this instance the researchers concluded that people with type 1 diabetes who have a tendency to develop low blood sugar during exercise should consider performing their resistance exercise first – which is often the way crossfit workouts are structured and how Mark workouts out.  

‘Eating clean’

Yet, while regular exercise is part of Mark’s life, he says that diet remains the most important pillar of managing his diabetes.

Type 1 diabetes is treated primarily with insulin therapy either injected through shots or a pump that delivers it through a tiny tube placed under the skin. Although a diet change cannot prevent or eliminate the need for insulin in type 1 diabetics, they can still generally can eat most foods as they then give themselves a dose of insulin based on the carbohydrates in the meal they're eating.

Experts do recommend that people with type 1 diabetes consume the same sorts of healthy foods they recommend to everyone to prevent heart disease, cancer and other life-threatening conditions.

Mark however, says that he has noticed a big difference since he started eating ‘clean’.

“I will always need insulin, but by making conscious decisions about the food I eat it makes it so much easier to live with the disease. For a long time while growing up with diabetes I always felt like I could never really understand how it worked – what made my sugar levels go up and down, etc. After many years of self study and experience, however, I became more adept at handling the situation.”

“Then in 2011 I switched to eating ‘clean’, and for the first time I felt I could really manage my disease. I felt empowered, and it's that feeling I want to share with other diabetics by means of the health and lifestyle coaching I do.”

Training with type 1 diabetes

So while Mark is a great role model for type 1 diabetics, he does point out that its taken him a while to get the formula that works for him, right.

Before you jump into any heavy lifting exercise as a diabetic, Mark advises you check your blood sugar before you start your workout, during a workout and afterwards.

“If you go into the workout low, you risk passing out from hypoglycaemia. Normally you’d feel it though, as symptoms include shakiness, feeling hot and bothered, irritability, not making sense when speaking,” he says.

So if you’re at the gym and someone you know is a diabetic feels any of these symptoms and has very low blood sugar Mark says you need to get them sugar/honey/fruit juice – and put it in their mouth and under the tongue if they cannot do it themselves.

If they pass out, you will of course need to call an ambulance.

To find out more about Mark, his philosophy to coaching and how he can help you reach your health goals, click through to his about.me page here.


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