Recovery for the endurance athlete with Type 1 Diabetes

Many people living with type 1 diabetes live an active lifestyle, and there are numerous examples of individuals achieving incredible feats of physical endurance while living with the condition. Recently we published a detailed review on this topic in the Lancet Diabetes and Endocrinology. Below is the summary.

In contrast to athletes without diabetes, research specifically examining a post-exercise recovery routine is scarce, with most of the focus being placed on insulin or nutritional strategies to manage glycaemia before or during the exercise bout. A recent blog addressed some of this. The lack of research in this area is unfortunate because the post-exercise recovery period presents an opportunity for maximising training adaption and recovery, and the clinical management of glycaemia through the rest of the day and overnight.

To highlight this, a consensus statement on the post exercise recovery period for the endurance athlete living with type 1 diabetes has now been published (1). This blog will not discuss the entire document, but will highlight some key topics covered. The paper highlights three main topics:

The principles and time course of post-exercise recovery, highlighting the implications and challenges for endurance athletes living with type 1 diabetes;
Potential strategies for post-exercise recovery that could be used by athletes with type 1 diabetes to optimise recovery and adaptation, alongside improved glycaemic monitoring and management;
Technology and its potential to ease the burden of managing glycaemia in the post-exercise recovery period.

Strategies to maximise and facilitate post-exercise glycogen synthesis in athletes with type 1 diabetes

For the athlete with type 1 diabetes, maintaining blood glucose concentration within target range (4–10 mmol/l) adds an additional complexity that requires vigilance, frequent glucose monitoring, preferably by continuous glucose monitoring (CGM), and often insulin dose titration.

The potential for technology to aid post-exercise recovery

Self-adjusted insulin dosing is complex. Physical activity presents additional challenges, with most decision making based on personal trial and error. Developing decision support tools that are adaptable and easy to follow, that can be adjusted according to each individual’s needs, are likely to be useful for improving not only performance but also blood glucose management.

Developing decision support tools that are adaptable and easy to follow, that can be adjusted according to each individual’s needs, are likely to be useful for improving not only performance but also blood glucose management.

Rapid developments in technologies such as CGM, smart devices or wearables, and closed-loop systems, all contribute to the possibility of an increased time in range around exercise with less input by the user. CGM technology has also been essential in the ongoing development of artificial pancreas systems with the use of closed-loop automated insulin delivery (2). These systems combine sensor glucose measurement with insulin pumps with the use of an algorithm to direct insulin delivery.

Next-generation closed-loop systems that are under investigation integrate other signals such as heart rate, skin conductance, ventilation rate, and body temperature, and add other hormones such as glucagon, to help increase time in the target glycaemic range during and after exercise. Such technology might also help to reduce some of the psychological toll and cognitive burden that type 1 diabetes can have on the individual (3).

Researchers, clinicians, sports coaches, and athletes with type 1 diabetes are increasingly integrating different data sources to facilitate the decision making behaviours related to glycaemia, training, and nutrition to meet energy requirements. The rapid development of hybrid closed-loop systems is also helping to make insulin delivery more automated. It is important to note that athletes without diabetes are also using similar data tools (eg, glucose monitoring, food logging apps, wearables) to make decisions about their training and nutrition practices.

The rapid development of hybrid closed-loop systems is helping to make insulin delivery more automated.

Limitations of the consensus statement

The authors of the paper do recognise that there are limitations of this paper. Firstly, there is a paucity of published research done over the post-exercise period in people living with type 1 diabetes, meaning that many of the statements are based on our opinion and experience. Second, few studies have been done in female athletes living with type 1 diabetes, so this should be a key focus area in the future.

A wide variation in training and nutrition plans, insulin requirements, and experience an individual has with managing their glycaemia in different situations, strongly suggest that there will never be a one size fits all set of guidelines that can be applied to every athlete with type 1 diabetes. Everyone’s diabetes is different, and individuals react differently to exercise. It is important that people with diabetes understand how their blood glucose responds to exercise so they can manage these fluctuations and prevent hypoglycaemia or hyperglycaemia.