By Ffion Bardouille Thompson – Exercise Physiologist
When it comes to managing blood sugar, doctors encourage us to eat healthier and exercise more. But the question is WHY?
Risks associated with high blood sugar
Along with potential development of type 2 Diabetes Mellitus (T2D), chronically untreated high blood sugar levels may lead to.
- Loss of sensation in the extremities
- Blindness through damage to the small vessels of the eye
- Cardiovascular disease
- Kidney disease
- Foot problems such as ulcers
- Surgical intervention
What causes high blood sugar/ glucose?
Our body uses sugar for energy and naturally stores some of this sugar in our blood stream as glucose.
Blood sugar levels spike around 60-90 minutes after a meal.
These spikes are quicker and higher when eating refined sugar and slower when eating complex carbohydrates such as grains.
The liver then releases insulin in response to blood glucose spikes, this tells our body to store the glucose away in the liver and skeletal muscles.
Type 2 diabetes mellitus (T2D) occurs when blood glucose levels are continuously high, insulin levels become continuously high. Leading to decrease insulin sensitivity leaving the liver struggling to keep up.
Type 1 diabetes mellitus (T1D) is a chronic autoimmune condition in which the immune system attacks insulin creating cells. Type 1 diabetes mellitus is often diagnosed at a younger age but can also be diagnosed in adulthood.
How does exercise help?
- Increased Muscle mass
- Our body stores glucose as glycogen in the muscles and liver. If we have more muscle, we have more space in which to store the glucose. More muscle mass also means we utilise more glucose whilst at rest as well as when we move.
- Increased insulin sensitivity
- Maintaining a regular exercise routine has been shown to increase our sensitivity to insulin. Which is particularly useful in those who are prediabetic.
- Increase energy usage
- When we exercise, we burn energy. High intensity exercise relies on the breakdown of the glucose within our blood stream to provide energy quickly.
- Steady state exercise allows us to use up the glucose stored in our muscles and liver as well as body fat which in the long term can assist with weight loss.
- Regular aerobic exercise such as swimming, cycling, jogging or running are good ways to achieve this.
What type of exercise is best
The Australian physical activity guidelines recommend a minimum of 30 minutes of planned moderate intensity exercise at least 5 days a week.
As well as breaking up prolonged periods of sedentary behaviour particularly at home or in the workplace.
The effects for exercise on blood sugar levels are shown to be best with a variety of resistance training to build muscle mass and cardiovascular training to increase glucose utilisation.
How do I start?
If you require assistance in building a physical activity program to minimise the risk of developing T2D. Or if you have already been diagnoses with T1D or T2D and would like help in planning your exercise around blood sugar spikes and drops. The best person to contact is an Exercise Physiologist.
For the keen readers…
1) Exercise and Sports Science Australia position statement https://www.diabetesresearchclinicalpractice.com/article/S0168-8227(20)30438-1/fulltext#
2) Department of Health Physical activity Guidelines 24-hour movement guidelines for all Australians | Australian Government Department of Health, Disability and Ageing
3) Effects of exercise timing on metabolic health. Obesity Reviews, 24(10), p.e13599, Martínez‐Montoro, J.I., Benítez‐Porres, J., Tinahones, F.J., Ortega‐Gómez, A. and Murri, M., 2023 Effects of exercise timing on metabolic health-online copy available
4) Physical activity for the prevention and treatment of metabolic disorders.
Internal and emergency medicine, 8(8), pp.655-666.Montesi, L., Moscatiello, S., Malavolti, M., Marzocchi, R. and Marchesini, G., 2013. marchesini2013.pdf- online proof available
