Type 1 diabetesis a life long metabolic disorder, which manifests when the pancreas stopsproducing insulin; as a result type 1 patients are dependant on insulin forsurvival 1-2.However, regular physical activity for type 1 diabetescomprises with various health and cardiovascular benefits including: increasedinsulin sensitivity, maintaining persistent glycaemic control by energizingmuscle glucose uptake and promotes good quality of life with diabetes 3-5. Thus,it would be advised to the client to consider adhering to regular physicalactivity post marathon due to the health benefits with diabetes and improvedinsulin sensitivity. Blood glucose Monitoring & Exercise Before startingany training regimen, It’s essential to be aware of balancing type of physicalactivity levels, insulin dosing and tailored nutritional intake, in order tomaintain normal blood glucose levels: pre, during and post exercise to preventhypoglycaemia 6-9.
The American College of Sports Medicine guidelines suggestpeople living with type 1 diabetes participating in physical activity shouldaim to keep glucose levels prior, during and after exercise predominantly over5.5 mmol/L and essentially lesser than 13.8-16.7 mmol/L to preventhypoglycaemia episodes 10. This can be achieved by monitoring glucose 30minutes prior to exercise, every 30 minutes during exercise and followingexercise; this can help enhance metabolic control when exercising 7. If theseglucose levels aren’t achieved, it’s important to postponement exercise toestablish if ketones are present; if glucose levels are below 5mmol/L consumequick-acting carbohydrates approximately 15-20 grams and recheck glucose levelsto determine if exercise can be started 5. Training Session Consent & Preparations Running a marathon consists of running thedistance of 26 miles 11 and preparing for marathon training sessions is achallenging task especially for type 1 patients, which compromises of vasteffort and constant practice 11.
It’s not recognised if the client is aregular exerciser or has any other medical conditions that may restrict herfrom exercise (e.g. hypertension, blocked arteries etc.). Thus, before startingany form of exercise, it’s vital she obtains consent from her doctor to determineif she’s fully physical to fulfil both short and long duration and low and highintensity training sessions and the marathon itself before adhering to nutritionaland medication advise discussed below 12. Important Considerations During initial Training Sessions When startinginitial training sessions it’s important to start off with lighter exercises, asnon-regular exercises don’t have reduced glucose-controlling reaction to hypoglycaemia,only type 1 athletes or regular exercisers would have these physiologicalbenefits 13.
Thus, consider settingrealistic goals by starting with low intensity shorter runs covering shorterdistances and making way up steadily, this way the body would become accustomedto the exercise intensity, improve insulin sensitivity, which would help reducethe risk of hypoglycaemia 14. Insulin Adjusting& Exercise Most challenging scenarios of exercisingwith type 1 diabetes is adjusting correction insulin dose with nutrition andexercise, in order to prevent hypoglycaemia 15. Several aspects could affectglucose reactions to exercise such as: glucose levels prior to exercise,timing, type and intensity of exercise, timing of insulin injections and lastmeal consumed prior to exercise 15. Taking vast amount of insulin prior toexercise can cause hypoglycaemia, as it diminishes the amount of glucose that addsto the blood from the liver and taking smaller amount of insulin wouldpredispose to hyperglycaemia 16. Thus, it’s vital to reduce the dose ofinsulin with meals prior to exercise, which will again depend on the duration,time and intensity of the exercise session 16. The client is currently taking ‘Novorapid’insulin with meals. If the client decides to exercise after a meal Diabetes UKguidelines for insulin adjusting prior to exercise intensity 17 suggest: ifexercising within 30 minutes of short duration of mild exercise, its advised toreduce 25% of rapid-acting insulin.
If exercising for at least 60 minutes ofmoderate to high intensity exercise, a reduction of 50-75% of rapid-actinginsulin reduction is recommended and exercising for over 90 minutes reductionof rapid-acting insulin from 25 to 75% is advised. If exercising beforebreakfast consume minimal sugary fluids during exercise and take normal insulindose with breakfast post-exercise. If exercising after breakfast, reducenovo-rapid by 25% and consume lower calorie breakfast with usual insulin dosefor lunch and dinner 18. In regards to Lantus insulin taken at night; ifexercising couple days per week the dose of this long-acting insulin can besplit meaning it can be taken twice a day, which can allow the meal insulindose to be reduced prior to exercise 19. If exercising everyday Lantusinsulin can be reduced by 20-25% at night, which would help preventhypoglycaemia episodes the following morning 19.