Diabetes & Exercise

Insulin and blood glucose – the lock and key

Similar to a lock and key system, insulin is a hormone made by and released from the pancreas. It allows the body to use glucose (sugar) for energy. The key (insulin) is needed to unlock pathways which are required for the glucose to enter different systems in the body, most notably our musculoskeletal system. By allowing glucose into the muscle, insulin can maintain appropriate levels of glucose in the blood so that levels don’t go too high (hyperglycaemia), or too low (hypoglycaemia).

When the lock and key doesn’t work

When we consume sugary food or drinks, the pancreas releases insulin to clear glucose from the blood. Insulin resistance is when the body’s cells become desensitised to the presence of insulin, and cannot use it as a key to effectively allow glucose into the cell. When we continue to consume in excessive amounts, over and over, the pancreas releases more and more insulin to compensate. Over time, the cells become resistant to the presence of insulin and eventually the pancreas becomes burnt out and insulin production decreases. As a result, glucose stays in the blood, and the body experiences glucose intolerance. Glucose intolerance is the inability to remove glucose, resulting in hyperglycaemia (high glucose).

There are two types of Diabetes:

• Diabetes Mellitus (Type 2) is commonly diagnosed in adults and is characterised by an insulin resistance or an underproduction of insulin which leads to uncontrolled blood glucose levels. Type 2 Diabetes occurs over time typically as a result of being overweight, having an unhealthy diet and being physically inactive. These factors increase the levels of free fatty acids in the body which increases insulin resistance hence leading to Diabetes.
• Type 1 – occurs when the body’s immune system destroys the cells in the pancreas that produces and releases insulin. People with Type 1 need to inject insulin everyday

Exercise and insulin

Exercise can improve insulin sensitivity. This is the body’s ability to recognise and use insulin to remove glucose from the blood. As a result, blood glucose levels are lowered (improved glucose tolerance), and glucose is used for energy or stored by the liver for later use.

During exercise, the muscles can take glucose from the blood without the use of insulin, further lowering blood glucose levels.

Exercise and Glucose tolerance

Research shows that improved glucose tolerance deteriorates within 72 hours of the last exercise session. This highlights the importance of exercising regularly. In addition to maintaining control of your disease, the risk of all-cause mortality decreases as your levels of fitness improve. Interestingly, this only requires a moderate improvement in fitness!

Exercise and Insulin Sensitivity

Following bouts of training, sensitivity to insulin improves, and adipose (fat) tissue and skeletal muscle tissue is better able to take in blood glucose. This happens regardless of whether there are any changes in fat/muscle mass, lost or gained. Unfortunately, similar to the benefits of exercise for improving glucose tolerance, improved ability to detect and use also only lasts 72 hours. Therefore, regular activity is necessary to maintain improvement.

Other benefits of regular activity include:

• Reduced blood pressure (at rest and exercise)
• Improved blood flow and reduced demands on the heart, by improving the ability of the heart to pump blood to the body
• Improved ability of the body to take up and use oxygen
• Weight loss and weight control (NOTE: good nutrition and regular exercise combined are more effective than exercise alone)
• Reduced visceral fat (the dangerous kind)
• Reduced cardiovascular risk
• Decreases stress and improved overall mood

If you would like some guidance on exercise or have no idea where to start, please don’t hesitate to contact our friendly admin team and they will be able to book an appointment for you.