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

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?

The va

lue o

f exe

rcise

Types

of ex

ercise

Exerci

se in

tensit

y and

durat

ion

Effect

of ex

ercise

on bl

ood g

luco

se

Whe

n it i

s safe

to ex

ercise

Insu

lin ad

justm

ent f

or ex

ercise

Diet &

flui

d rep

lacem

ent f

or ex

ercise

Carboh

ydrat

e cou

ntin

g

0

10

20

30

40

50

60

70

Very confidentBroadly confidentNot so confidentNot confident at all

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 5.5• 75% 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

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 - 1

40 80 120

160

RecoveryExercise

Horm

on

e c

on

cen

trati

on

GHCortisol

GlucagonTestosterone

NoradrenalineAdrenaline

Time (min)Baseline 0 20 40 60

Gro

wth

Ho

rmo

ne C

on

cen

trati

on

(

g.l-

1 )

0

10

20

30Exercise

or

Rest

#

#

caa


Gro

wth

Ho

rmo

ne C

on

cen

trati

on

(

g.l-

1 )

0

10

20

30Exercise

or

Rest

#

#

ca


Gro

wth

Ho

rmo

ne C

on

cen

trati

on

(

g.l-

1 )

0

10

20

30Exercise

or

Rest

#

#

caa


RestResistance

Sprint

Endurance

Kate L. Gilbert et al 2008


Aerobic

Anaerobic

Summary 1

• With Aerobic exercises blood sugars will tend to fall.

• With anaerobic exercise blood sugars will tend to rise


• Type of exercise• Intensity of the exercise


Exercise intensity

0 20 40 60 80 100

V02 max

Hor

mon

e co

ncen

trat

ion

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

E F

0

2

4

6

8

10

12

14

16

18

20

-10 0 10 20 30 40 50 60

time (min)

seru

m insulin

(m

IU/l)

b

c

pre- end

SprintWeight trainingEndurance

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

120

140

160

180

200

60

80

100

120

140

160

Hea

rt r

ate

Sys

tolic

BP

Rest Exercise Recovery

Borg Scale

7 >1686 1311 15149 10 12

Under 6 = Rest

Over 16 = Very Heavy

Very Light Light Moderate Heavy

<90bpm ~100-110bpm ~120-130bpm 146-160bpm

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


• 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 bodyInsulin resistance

Increased lipolysisIncreased glucoseOutput

Pre

Exercise

Hormones during exercise.

TG

FFA’sGlycerol

Glycogen

Glucose Glucose

CortisolAdrenaline

NoradrenalineGH

Amino acids

CortisolGlucagon

AdrenalineNoradrenaline

Glucagon

MuscleLiver

Glucose

Insulin

PyruvateCo2

T4T3

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 bodyInsulin resistance

Reduced lipolysis and decreased glucose output

Pre

Exercise

Hormones during exercise in diabetes.

TG

FFA’sGlycerol

Glycogen

Glucose Glucose

CortisolAdrenaline

Noradrenaline

GHAmino acids

CortisolGlucagon

AdenalineNoradrenaline

Glucagon

MuscleLiver

Glucose

Insulin

PyruvateCo2

T4T3

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


• 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

0

2

4

6

8

10

12

14

30 60 120 240

Time mins

Pla

sma

glu

cose

mm

ol.

l-1

No InsulinInsulin

Actrapid or Humulin S

Novorapid or Humalog

Different insulin regimes

0 2 h 4 h 6h

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


• 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 s’wich, 1 slice toast , 200g baked beans

1 hr 45 training/yoga - refuel 200ml sk milk, 500ml water

Dinner - Liver, bubble & squeak, yoghurt, herbal tea3 February 2012 Janet Gorton Diabetes

Specialist Dietitian Taunton & Somerset NHS Foundation Trust

Energy Expenditure

• Most athletes expend

45-50 kcal/kg body weight

• 63kg 2835 – 3150• 90kg 4050 – 4500 kcals

• Other factors



14 -16 pints skimmed Milk63 kg

Carbohydrate requirements body mass, exercise intensity & duration

Training LoadCHO

Recommendations

Very light training

(low intensity exercise or skill-based exercise)3-5 g.kg-1.day-1

Moderate intensity exercise for 1 hr/day 5-7 g.kg-1.day-1

Moderate to high intensity exercise for 1-3 hrs/day 6-10 g.kg-1.day-1

Moderate to high intensity exercise for 4-5 hrs/day 8-12 g.kg-1.day-1

2010 International Olympic Committee (IOC) Concensus statement on Sports Nutrition

*Burke, L.M., (2010)

Hormones post exercise.

TG

FFA’sGlycerol

Glycogen

Glucose Glucose

Amino acids

MuscleLiver

Glucose

PyruvateCo2

Insulin

CortisolGH

Cortisol

Insulin

Recovery

• Protein and Carbohydrate together improve glycogen storage 2 hours post exercise

• 4 carb : 1 protein• 20-25 g protein optimal• Total 1.2g/kg


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

<3.5 3.5-5.6 >145.7-6.9 7.0-14

20 gCarb

Wait45 min

Recheck BM

20 gCarb

Wait15 min

Ketone PosCorrectionDose

Ketone Neg30%CorrectionDose

Proceed to exercise

Additional15 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


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 insulinCarb 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 startDo not exerciseCheck BG

<3.5 3.5-5.6 >145.7-6.9 7.0-14

20 gCarb

Wait45 min

Recheck BM

20 gCarb

Wait15 min



Proceed to exercise

Additional15 gCarb

Post exercise if BG > 14 mmol/l give 30% usual correction and test 2 hours laterIf exercising evening reduce background by 10%

Replace Carb as perChoice of regime

Step 4: More complex advice

Case 2

John is now on a basal bolus regime of novorapid 6-10 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.


Options

Insulin regime

Injection sites

Size of needles

Overall diet

Carb loading


10 Second Sprints





Reducing pre-meal bolus insulin before exercise

Exercise intensity (% VO2max) % Dose reduction

30 min of exercise 60-min of exercise

25 25 50

50 50 75

75 75 -

Rémi Rabasa-Lhoret Diabetes Care 24: 625-630

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 90-60 – 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 144-120 – 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)*

>144.6 -5.6(5.7-7.0)*

5.7-14(7.0-14)*

30 gCarb

Wait15 min



Proceed to exercise

Additional15 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 perTable 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.


Options

Insulin regime

Injection sites

Size of needles

Overall diet

Carb loading


10 Second Sprints





Hormones post exercise in diabetes.

TG

FFA’sGlycerol

Glycogen

Glucose Glucose

Amino acids

MuscleLiver

Glucose

Insulin

CortisolGH

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


10 Second Sprints





Hormones during exercise in diabetes.

TG

FFA’sGlycerol

Glycogen

Glucose Glucose

CortisolAdrenaline

Noradrenaline

GH

Amino acids

CortisolGlucagon

AdenalineNoradrenaline

Glucagon

MuscleLiver

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

[email protected]

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

Documents

exercise exercise intensity

type of exercise slide

intensity of exercise

physical exercise

type of exercise intensity

minutes slide

gcarb post exercise

aerobic anaerobic slide