Managing glucose before, during and after exercise in type 1 diabetes Rob Andrews University of Bristol/ Taunton and Somerset Foundation Trust

Fitness Insulin requirement Lipids Endothelial function Mortality Blood pressure Beta cell function Glycaemic control Fitness Insulin requirement Lipids Endothelial function Mortality Insulin resistance CVD Wellbeing (only children) Microvascular complications Osteoporosis Cancer CVD Wellbeing Microvascular complications Osteoporosis Cancer Beta cell function Blood pressure Glycaemic control Beneficial Uncertain / Limited data Physical activity Type 2 diabetes Type 1 diabetes Beneficial Uncertain / Limited data

So what do Specialist in Diabetes know about exercise and diabetes?

Result of survey of diabetes HCP – No 138

Exercise and blood sugar HCP knowledge on what to do with high BG (>13), and slightly low 3.6 was good but 75% HCP did not know what to do with patients who had has severe hypo night before 50% HCP did not know what to do with BG of % did not know what to do with blood sugar of 1.8 Doctors no better than nurses or dietitians.

Exercise and insulin Fast acting insulin 1/3 of HCP not clear as what should be done with fast acting insulin if exercising 2 hours after a meal 55% HCP not sure what should be done with fast acting insulin if exercise before breakfast Long acting insulin 50-80% HCP (dependent on time of day) not knowing what to do with background when exercising Doctors significantly worse than nurses or dietitians.

Exercise and injection sites Where to inject 1/3 of HCP did not know the injection sites that should be avoided when cycling or lifting weights. Doctors no better than nurses or dietitians.

What you need to know Type of exercise

Aerobic exercise is physical exercise of relatively low intensity that depends primarily on the aerobic energy- generating process.

Aerobic Hiking Golf Road cycling Cycle tour Mountain biking Distance running Distance swimming Triathlon, etc

Anaerobic exercise Anaerobic exercise is exercise intense enough to trigger use of non oxygen using metabolism. It normally last less than 2 minutes

Anaerobic exercises Weight lifting Body Building Dressage Fencing Track and field events (Javelin, Shot put, Long jump, Pole-vault, High jump, Sprinting) Archery Wrestling

Hormonal response to exercise RecoveryExercise Hormone concentration GH Cortisol Glucagon Testosterone Noradrenaline Adrenaline

Hormonal response to exercise - 2 Rest Resistance Sprint Endurance Kate L. Gilbert et al 2008

Hormonal response to exercise - 3 Aerobic Anaerobic

Summary 1 With Aerobic exercises blood sugars will tend to fall. With anaerobic exercise blood sugars will tend to rise

What you need to know Type of exercise Intensity of the exercise

Hormonal response to exercise - 4 Exercise intensity V02 max Hormone concentration Dependent Exercise intensity Type of exercise Competition Body temperature Age ? Blood glucose Independent Circadian rhythm Meal time Menstrual cycle Sex

Fuels used during exercise

Lactate during exercise

Insulin in response to different exercises EF Sprint Weight training Endurance

Summary 2 As the intensity of exercise rises Glucose becomes the major fuel Lactate levels rise Insulin levels rise to compensate for this

Cardiovascular response to exercise Heart rate Systolic BP RestExerciseRecovery

Borg Scale 7> Under 6 = Rest Over 16 = Very Heavy Very LightLight Moderate Heavy <90bpm~ bpm~ bpm bpm

Summary 3 Exercise induced HR rise is Less in patients with Type 1 Diabetes Thus using Predicted HR for training is not very useful in patients with Type 1 Diabetes One helpful scale that can be used is the borg scale

What you need to know Type of exercise Intensity of the exercise The length of the exercise

Normal response to exercise GH and Cortisol rise Activation of CNS Insulin levels fall Glucagon levels Rise Adrenaline levels Rise Prepares body Insulin resistance Increased lipolysis Increased glucose Output Pre Exercise

Hormones during exercise. TG FFAs Glycerol Glycogen Glucose Cortisol Adrenaline Noradrenaline GH Amino acids Cortisol Glucagon Adrenaline Noradrenaline Glucagon Muscle Liver Glucose Insulin Pyruvate Co2 T4 T3

Summary 4 Fuel for exercise comes from three sources Muscle (few minutes) Liver (40 minutes) Fat breakdown And is under the control of hormones

Response to exercise in diabetics GH and Cortisol rise Activation of CNS Insulin levels fall Glucagon levels Rise Adrenaline levels Rise Prepares body Insulin resistance Reduced lipolysis and decreased glucose output Pre Exercise

Hormones during exercise in diabetes. TG FFAs Glycerol Glycogen Glucose Cortisol Adrenaline Noradrenaline GH Amino acids Cortisol Glucagon Adenaline Noradrenaline Glucagon Muscle Liver Glucose Insulin Pyruvate Co2 T4 T3

Summary 5 In patients with T1DM less fuel comes from the liver and fat, with the fat more effected than the liver. So glucose may be needed for short bouts of exercise and definitely will be needed for longer durations of exercise

What you need to know Type of exercise Intensity of the exercise The length of the exercise When they are exercising in relation to their fast acting insulin

Insulin Sensitivity: 1922 Lawrence Time mins Plasma glucose mmol.l-1 No Insulin Insulin

Actrapid or Humulin S Novorapid or Humalog Different insulin regimes 02 h4 h6h Hypo risk Hypo

Summary 6 Glucose falls quicker during exercise when insulin is around. Adjustments in insulin or glucose intake will thus need to be made if exercising within 2-4 hours of taking insulin

What you need to know Type of exercise Intensity of the exercise The length of the exercise When they are exercising in relation to their fast acting insulin What time of day they are exercising

Changes in insulin sensitivity with exercise

Changes in glucose with exercise

Summary 7 Insulin sensitivity increases During exercise For an hour after exercise At 6-8 hours post exercise Glucose thus needs to be watched at 2 time points

How to do it!

Step 1: Dietary intake

Diet 33 yr female, diagnosed type 1 DM age 16 Training for a triathlon Weight currently 63 kg, height 1.65 m Her current problems – dips and highs in glucose levels and running out of energy in training. 3 February 2012 Janet Gorton Diabetes Specialist Dietitian Taunton & Somerset NHS Foundation Trust

Food diary Breakfast - 40g (bowl) whole oats, 100 ml skimmed milk & water, small banana, actimel 1 hr training - refuel 350ml flavoured sk milk Lunch - Egg swich, 1 slice toast, 200g baked beans 1 hr 45 training/yoga - refuel 200ml sk milk, 500ml water Dinner - Liver, bubble & squeak, yoghurt, herbal tea 3 February 2012 Janet Gorton Diabetes Specialist Dietitian Taunton & Somerset NHS Foundation Trust

Energy Expenditure Most athletes expend kcal/kg body weight 63kg 2835 – kg 4050 – 4500 kcals Other factors 3 February 2012 Janet Gorton Diabetes Specialist Dietitian Taunton & Somerset NHS Foundation Trust

pints skimmed Milk 63 kg

Carbohydrate requirements body mass, exercise intensity & duration Training Load CHO Recommendations Very light training (low intensity exercise or skill-based exercise) 3-5 g.kg-1.day-1 Moderate intensity exercise for 1 hr/day5-7 g.kg-1.day-1 Moderate to high intensity exercise for 1-3 hrs/day6-10 g.kg-1.day-1 Moderate to high intensity exercise for 4-5 hrs/day8-12 g.kg-1.day International Olympic Committee (IOC) Concensus statement on Sports Nutrition *Burke, L.M., (2010)

Hormones post exercise. TG FFAs Glycerol Glycogen Glucose Amino acids Muscle Liver Glucose Pyruvate Co2 Insulin Cortisol GH Cortisol Insulin

Recovery Protein and Carbohydrate together improve glycogen storage 2 hours post exercise 4 carb : 1 protein g protein optimal Total 1.2g/kg 3 February 2012 Janet Gorton Diabetes Specialist Dietitian Taunton & Somerset NHS Foundation Trust

Step 2: Starting blood sugars

Case 1 - starting blood sugar Rob is a keen runner When he gets up for his morning run his blood sugar is 3.5. What would you advice? If he had had hypo over night would this change your management?

Starting blood sugars Has Blood sugar been <3.5 in last 24 hours? Do not exerciseCheck BG No Yes < > g Carb Wait 45 min Recheck BM 20 g Carb Wait 15 min Ketone Pos Correction Dose Ketone Neg 30% Correction Dose Proceed to exercise Additional 15 gCarb

15g Carbohydrate 3 jelly babies 160 ml fruit juice 9 jelly beans 5 fruit pastilles 250 ml 6-8% carbohydrate sports drink 2 wine gums 1 mini can cola 1 fruit lolly 3 February 2012 Janet Gorton Diabetes Specialist Dietitian Taunton & Somerset NHS Foundation Trust

Step 3: Starting advice

Case 2 -training for marathon John is 26 and has had type 1 diabetes for 3 years and is on mixtard 30 22/24. He does little exercise but is keen to do the london marathan in 6 months time. What advice would you give him?

Options Insulin regime Injection sites Size of needles Overall diet Carb loading Carb replacement during exercise 10 Second Sprints Replenishment post exercise Alteration insulin dose pre exercise Alteration insulin dose post exercise Bolus insulin Carb during exercise

Case 2 Change insulin to QDS. Access dietary needs. Advice about starting glucoses Advice about carb Ex

3 strategies Additional carbohydrate Insulin reduction Combination of both

Basic strategy Ex carb estimate 15g carbohydrate per 30 minutes exercise. Add on half time exercise for recovery Example – Mark exercises for 60 minutes. So takes 15g at start, 15g at 30 minutes and 15g at end

Semi -quantitative strategy for Ex carb estimate Takes into account body weight 1g glucose/kg/hr exercise Example – Mark weighs 90 kg and exercises for 60 minutes. So takes 30g at start, 30g at 30 minutes and 30g at end

Quantitative strategy for Ex carb estimate Takes into account body weight and intensity of exercise Uses tables or CGM readings. Example – Mark weighs 90 kg wants to cycle for 1 hour at average 18 miles per hr.

Semi -quantitative strategy for Ex carb estimate

Quantitative strategy for Ex carb estimate Takes into account body weight and intensity of exercise Uses tables or CGM readings. Example – Mark weighs 90 kg wants to cycle for 1 hour at average 18 miles per hr. Need 165 grams so 40 grams start, 40 grams 30 minutes and 85 grams at end

Simple start Do not exerciseCheck BG < > g Carb Wait 45 min Recheck BM 20 g Carb Wait 15 min Ketone Pos Correction Dose Ketone Neg 30% Correction Dose Proceed to exercise Additional 15 gCarb Post exercise if BG > 14 mmol/l give 30% usual correction and test 2 hours later If exercising evening reduce background by 10% Replace Carb as per Choice of regime

Step 4: More complex advice

Case 2 John is now on a basal bolus regime of novorapid TDS and Levemir BD 12/10. He has started to run 3 times a week but finds it difficult to run more than 30 minutes and is having frequent hypo during his runs. What advice would you give him?

Options Insulin regime Injection sites Size of needles Overall diet Carb loading Carb replacement during exercise 10 Second Sprints Replenishment post exercise Alteration insulin dose pre exercise Alteration insulin dose post exercise Bolus insulin Carb during exercise

Reducing pre-meal bolus insulin before exercise Exercise intensity (% VO2max) % Dose reduction 30 min of exercise60-min of exercise Rémi Rabasa-Lhoret Diabetes Care 24:

More complex strategy for insulin Working out how much need to reduce by -Work out how many grams you will burn -Decide how much carbs you will take -Divide difference by carb/insulin ratio to calculate reduction in insulin required. -Then decide how you will make this reduction. Can be done by -Reduction bolus -Reduction background -Combination

Example bolus reduction Mark wants to cycle for one hour after breakfast. He normal takes insulin in ration 6:1. For breakfast he has 90 grams of carbohydrate. On his ride he will consume 60grams of carb. Difference is – 30 grams So needs to take insulin to cover 30 grams – 5 units, as opposed to his normal 15 units.

Example combined reduction Mark plans to play golf 3 hours after breakfast. The calories he will burn on the round is 144 grams. Whilst on the round he will take 30 grams every hour ( round takes 4 hours). Difference is – 24 grams Ratio 6-1. So needs to reduce insulin by 24/6 =4 units less of his am background Normally takes 16 normally so reduce down to 12

Carb + insulin plan Do not exerciseCheck BG <4.5 (<5.6)* > ( )* (7.0-14)* 30 g Carb Wait 15 min Ketone Pos Correction Dose Ketone Neg 30% Correction Dose Proceed to exercise Additional 15 g Carb Recheck BM Pre breakfast no change insulin * 1-2 after breakfast or lunch reduce pre dose by 50% Before lunch & 2 hours after break no change* Before supper & 2 hours after lunch reduce morning background by 10% Between supper & bed decrease pre by 50% and consider decreasing pm background by 10% Replace Carb as per Table every hour

Step 5: Problems

Case 3 Robert is an elite athlete. He is gradually building up the length of his runs. In spite of good carbohydrate intake and replacement during exercising and dose reduction of his insulin prior to his training he is having problems with hypos during training. What advice would you give him?

Options Insulin regime Injection sites Size of needles Overall diet Carb loading Carb replacement during exercise 10 Second Sprints Replenishment post exercise Alteration insulin dose pre exercise Alteration insulin dose post exercise Bolus insulin Carb during exercise

Hormones post exercise in diabetes. TG FFAs Glycerol Glycogen Glucose Amino acids Muscle Liver Glucose Insulin Cortisol GH Cortisol Insulin

Replenish stores Eat within one hour of exercise Take bolus with it

Case 4 Sally is a university runner. She use to do the bulk of her training in the afternoon. Recently she has had to change her training to the morning. Prior to training she has breakfast and takes a reduced dose of her insulin. Whilst running she takes glucose regularly but finds it difficult to keep up with her requirements and often goes hypo. What advice would you give her?

Options Insulin regime Injection sites Size of needles Overall diet Carb loading Carb replacement during exercise 10 Second Sprints Replenishment post exercise Alteration insulin dose pre exercise Alteration insulin dose post exercise Bolus insulin Carb during exercise

Hormones during exercise in diabetes. TG FFAs Glycerol Glycogen Glucose Cortisol Adrenaline Noradrenaline GH Amino acids Cortisol Glucagon Adenaline Noradrenaline Glucagon Muscle Liver Glucose Insulin

Increasing noradrenaline Short Sprints Caffeine drinks

Continuous vs continuous + intermittent Riddell MC Diabetic Medicine 2011

Continuous vs continuous + intermittent Riddell MC Diabetic Medicine 2011

Avoid glutamine

Summary Decide what type of sport it is Access and give advice on diet Simple advice about starting blood sugars Simple carb advice for during and after exercise Reassess

Conclusion With advice and support patient with Type 1 diabetes can exercise safely and compete at the highest level. In the future being able to give exercise advice may become more important Contact details