Getting in the game: Nutrition and exercise for adults with type 1 diabetes
At Type One Summit 2019, ex-pro cyclist with type 1 diabetes (T1D) and session facilitator Justin Morris called it his favourite topic of the day. After all, who doesn’t love food and getting out there and getting active, right? Keep reading to find out more about the nutrition and exercise session designed especially for adults with T1D, from the 2019 JDRF Type One Summit.
Session Facilitator & Speakers
Justin Morris was the perfect choice to host a session on nutrition and exercise. He has travelled the world as a pro-athlete, training and competing all whilst living with T1D. Justin opened the session by introducing the two presenters, Dr Sybil McAuley and Dr Kirstine Bell.
Dr Kirstie Bell is a dietitian and credentialled diabetes educator (CDE) and research fellow at Sydney Uni. Following a PhD in T1D and food insulin index, Dr Bell continued her research at Harvard and the University of Newcastle. Dr Bell is currently running clinical trials in insulin dosing for fat and protein as well as a T1D prevention trial. Dr Bell’s work has been incorporated into international diabetes guidelines for care. She has also spent 6 months living in the deep snow of Montana, studying dietetics.
About the session
Dr Sybil McAuley took to the stage first to talk general principles of exercise glucose and insulin. She acknowledged that motivations to exercise might be quite different depending on the goal – weight loss, fitness, competition, enjoyment or all of these – and that’s how we need to approach T1D management and exercise. Your individual motivation may point you down a path of how you will adjust insulin or have supplemental carbs. For the general population, recommended exercise guidelines are 150-300 minutes of moderately intense activity over the week. Or around half of that for vigorous exercise. We should aim for muscle strengthening twice a week.
“How can we work type 1 diabetes management, so that exercise doesn’t impair this. It can be tricky. It can be hard to get balance. But it can be done and has been done. Justin is a great example of this.”
Dr McAuley explained that many Olympic athletes have been diagnosed before they reached such a level, and during their peak. British rower, Sir Steven Geoffrey Redgrave, won a number of medals before he was diagnosed with T1D and a fifth Olympic gold after diagnosis. US swimmer, Gary Hall Jr, also won an Olympic gold medal while living with T1D.
“Every sport you can think of has been conquered at elite level.”
So, what are some of the barriers to exercising with T1D, according to Dr McAuley’s research?
- The fear of hypos
- Going high with exercise
- Instability of levels
- Own fitness level
- Health status
- Being confident with T1D management and strategies
What are the factors to consider when planning an exercise strategy?
- Are you on a pump or injections?
- What are your exercise goals?
- The timing of your meal before you exercise
- Your starting blood glucose level in considering whether to have supplemental carbs.
- The length of exercise and if supplemental carbs are needed. e.g. marathon runners will need to refuel
- The type of exercise – light, moderate or intense
- Whether the exercise is planned or unplanned
Dr McAuley explained that all these factors play into the body’s hormone effects – adrenaline and cortisol released during exercise affect the body’s glucose response.
Knowing what type of exercise you’re going to do is vital. There are two types – aerobic and anaerobic. Aerobic is when oxygen is supplied to muscles, like during a long run or ride. It’s exercise of a continuous moderate intensity that can be sustained for a period of time. During aerobic exercise, it’s expected that glucose levels will trend down – and you generally might reduce insulin onboard quite a while in advance.
Anaerobic is exercise in short sharp bursts e.g. sprints, interval training or lifting heavy weights. It causes lactate in blood to rise. High bursts of activity mean glucose can go up quite quickly, as adrenaline is raised. Due to this, the insulin requirements for anaerobic exercise are much higher.
For a mixed exercise picture which includes both aerobic and anaerobic e.g. a sports match or gym session, your blood glucose levels might go up or down. It’s really hard to know without being familiar with your body’s own response.
