The EXTOD/JDRF PEAK study day, held in Birmingham on October 2017, was the result of collaboration between EXTOD (Exercise for Type One Diabetes) and the JDRF PEAK (Performance in Exercise and Knowledge) project. Through the leadership of Dr Rob Andrews, Dr Parth Narendran and Dr Ian Gallen, EXTOD has been running study days on the management of type 1 diabetes for a number of years.
The programme for this event was put together by an international faculty, and covered type 1 diabetes and exercise management in both adults and children. In the morning, lectures were followed by practical workshops on nutrition, at both basic and advanced levels. The afternoon sessions concentrated on the practical aspects of managing exercise.
The day opened with a video message from Sir Steven Redgrave, winner of five Olympic gold medals in rowing, and was followed by an overview of normal exercise physiology from Prof Anton Wagenmakers of Liverpool John Moores University. Understanding normal exercise physiology and the systems used to fuel exercise is a key component of advice in type 1 diabetes. Prof Wagenmakers used examples from the world of athletics to explain energy systems: the 60 and 100 m to explain ATP production from the phosphocreatine (PCr) or phosphagen system; the 200 and 400 m sprints to explain anaerobic glycolysis; and the marathon to explain aerobic fuel systems.
The impact of the different energy systems in type 1 diabetes was covered by Prof Michael Riddell from York University, Toronto. Many of the children and young people (CYP) that we work with will do mixed exercise that results in variable blood glucose effects owing to the different components of the activity. This means blood glucose responses vary for the same activity between young people we work with. Figure 1 explains the differences in blood glucose levels seen with different activity types.
Figure 1. Variability in blood glucose responses to different forms of exercise in people with type 1 diabetes (Riddell et al, 2017).
Prof Riddell also discussed the impact of starting blood glucose levels on response to exercise, highlighting that starting with a higher blood glucose level is not necessarily protective against hypoglycaemia. Data collected from sports camps run by Prof Riddell’s lab, and presented at the ADA (Zaharieva et al, 2017), showed how those with the highest initial blood glucose levels often have the largest fall in levels during aerobic exercise. It is interesting to note that these data also show that some individuals have the opposite blood glucose response to the predicted effect and, therefore, blood glucose monitoring is the only way for an individual to know what happens to their blood glucose levels. In clinical practice, we should be encouraging young people to begin exercise with a blood glucose level above 5 mmol/L and below 10 mmol/L.
Sessions on pre- and post-exercise management were delivered by Dr Richard Bracken (University of Swansea) and Dr Ian Gallen (Royal Berkshire Hospital). Dr Bracken’s session reminded us all of the importance of using every clinical encounter to promote physical activity to all people living with type 1 diabetes. Epidemiological data show that, generally, CYP with type 1 diabetes are less active than their peers. Dr Ian Gallen discussed hypo- and hyperglycaemia prevention and touched upon some of the difficulties that may be experienced with hyperglycaemia post exercise. This can be improved by ensuring that CYP conduct a “cool down” (gentle exercise) at the end of exercise. For those young people using insulin pump therapy, avoiding disconnection during exercise helps prevent hyperglycaemia, especially if the exercise is predominantly anaerobic or competitive. If disconnection is unavoidable, then strategies for insulin replacement are needed.
The JDRF PEAK project started after a survey identified that one of the barriers to an active lifestyle for people living with type 1 diabetes was access to advice and support from healthcare professionals. A summary of the advice and evidence presented at the study day can be found by reading the consensus statement by Riddell et al (2017).
References
Riddell MC, Gallen IW, Smart CE et al (2017) Exercise management in type 1 diabetes: a consensus statement. Lancet Diabetes Endocrinol 5: 377–90
Zaharieva DP, Beck RW, Tansey M et al (2017) Blood glucose responses to aerobic exercise in youth with T1D. Presented at: American Diabetes Association 77th Scientific Sessions (poster 761-P/761). San Diego, USA, 9–13 June
