Regular exercise is an important part of good diabetes management as it lowers blood glucose levels and boosts the body’s sensitivity to insulin, countering insulin resistance. Recent research suggests that exercise can even slow or prevent the development of macular degeneration and may benefit other common causes of vision loss, such as glaucoma and diabetic retinopathy.
For people with diabetes type 1 it is important to address how to balance blood glucose levels during and after exercise. The blood sugar response can be difficult to predict, with exercise sometimes increasing the risk of falling blood sugar levels — known as hypoglycaemia — or other times causing blood sugar to rise. Glucose levels must be closely monitored, since having a “hypo” which can lead to dizziness, disorientation, anxiety, etc., is a major barrier stopping people with diabetes from incorporating exercise into daily life.
Many experts recommend that people with type 1 diabetes, who want to maintain an active lifestyle, exercise when their blood glucose levels are normal or modestly elevated, but not when circulating insulin concentrations are raised, such as shortly after a bolus or prandial dose of insulin. Finding the right balance can be challenging.
An international team of experts have laid out the world’s first standard guidance on how people with diabetes can use modern glucose monitoring devices to help them exercise safely. Due to the complexity of the glucose monitoring systems, both individuals with diabetes and their healthcare professionals may struggle with their interpretation of information. That’s one of the main reasons the guidelines were developed.
The guidelines look at the evidence from glucose monitoring technology and use it as the basis for clear guidance for exercise in adults, children and adolescents with type 1 diabetes. The guidance covers areas like carbohydrate consumption and safe glucose thresholds. The idea is that it should serve as an initial guidance tool, which can then be tailored for the individual patient in consultation with health professionals.
According to one of the authors, the guidance is a landmark agreement which could end up making a real difference to people with type 1 diabetes as it will help them to obtain the health benefits of exercise, whilst minimizing wide fluctuations in their blood glucose level.
The guidelines include extensive advice and recommendations for exercise preparations, issues to consider during exercise and steps to bet taken post exercise. For example, the guidelines note that target sensor glucose ranges should be between 7.0 mmol/l and 10.0 mmol/l and slightly higher for those with an increased risk of hypoglycemia. If sensor glucose levels are elevated, individuals should monitor blood ketone levels, and insulin correction may be performed. It also states that exercise should be suspended if sensor glucose level reaches <3.9 mmol/l and, if below 3.0 mmol/l, exercise should not be restarted.
The recommendations will need to be regularly updated to provide the best and most robust evidence-based recommendations for people with type 1 diabetes using continuous glucose monitoring devices during exercise. But this first edition is already a good start.