Module 9 Lecture 1 Nutrition for Athletes with Diabetes

Question 1

Type I vs. type II diabetes

Answer 1

• type I: Destruction of insulin producing beta-cells of the islets of Langerhans in the pancreas and is treated with exogenous insulin and beta cell transplent and usually diagnosed in childhood or adolescence (autoimmune or idiopathic) ~10%
• type II: Typified by insulin resistance rather than insulin inadequacy usually due to obesity and related to exercise and diet and seen mid-life ~90%

Question 2

blood glucose levels that are higher than normal, but not yet high enough to meet the diagnostic criteria for Type I or Type II DM

Answer 2

pre-diabetes

Question 3

Conditions of pre-diabetes

Answer 3

• Fasting plasma glucose level of 7.0 mmol/L or
• A1C of 6.5% or higher

Not everyone with prediabetes will develop Type 2 DM, but, left unactioned, many people will.

Question 4

Other Forms of Diabetes/Diabetic Symptomology

Answer 4

• Gestational Diabetes
• Genetic defects of beta-cell function
• Genetic defects in insulin action
• Diseases of the exocrine pancreas
• Endocrinopathies
• Drug or chemical induced infections
• Uncommon forms of immune-mediated Diabetes

Question 5

Health Benefits of Physical Activity for People with Diabetes

Answer 5

Reduced risk for:
* CVD
* Obesity and overweight
* Diabetes related co-morbidities (Neuropathy, Nephropathy)

Increased:
* Sense of well-being
* Control and self-efficacy

Question 6

Effects of Physical Activity on Blood Glucose Control

Answer 6

• Increases peripheral insulin sensitivity
• Reduces insulin requirements
• Endogenous and exogenous
• Improves glucose tolerance
• Ability to clear glucose from blood

May produce rapid fluctuations in blood glucose levels if dietary intake is not balanced with physical activity and oral hypoglycemic agents and/or exogenous insulin (especially T1D)

Question 7

What is the goal of managing diabetes in athletes?

Answer 7

Goal in both cases is to avoid hypoglycemia and keep BG levels in the normal range (Normal = 4 to 7 mmol/L)
* Differences exist in the management of diabetes in Type 1 versus Type II diabetes in athletes
* Hypoglycemia is more likely in Type I cases and in Type II individuals being tx with insulin

Question 8

Diabetes Management – Type II Diabetes

Answer 8

in general blood glucose levels are less labile
* Individuals who control their diabetes with diet and exercise only are NOT at increased risk for hypoglycemia during activity
* Individuals with diabetes who are being treated with oral hypoglycemic agents are at low to moderate risk of suffering from hypoglycemia during sport

Question 9

how to manage T2D if being treated with insulin

Answer 9

at risk for hypoglycemia
* Monitoring is important
* Need to monitor and scale insulin dosage
* Adjust CHO intake as needed for balance
* Should follow similar guidelines to Type I

Question 10

Why is Type I diabetes more of an issue?

Answer 10

Individuals lack the ability to maintain fuel homeostasis during exercise
* Hepatic glucose production may not match muscle glucose utilization
* Result can be wildly fluctuating blood glucose levels
* Significant risk for hypoglycemia if not monitored

Question 11

What exercise physiology normally happens in terms of serum glucose?

Answer 11

Question 12

What are the counter regulatory hormones?

Answer 12

• glucagon
• growth hormone
• cortisol
• epinephrine
• norepinephrine

The net effect of these counter regulatory hormones is to maintain glucose homeostasis

Question 13

Describe glucagon

Answer 13

(alpha cells in pancreas)
* Most efficient stimulator of gluconeogenesis
* Requires liver glycogen stores to acutely increase BG

Question 14

Describe Growth Hormone

Answer 14

(anterior pituitary)
* Promotes lipolysis
* Increased hepatic glucose production

Question 15

Role of cortisol

Answer 15

(adrenal cortex)
* Enhances gluconeogenesis

Question 16

Role of epinephrine

Answer 16

(adrenal medulla)
* Inhibit insulin secretion
* Increase glucose secretion from liver and lactate from muscle

Question 17

Role of norepinephrine

Answer 17

(adrenal medulla)
* Inhibit insulin secretion
* Increase glucose secretion from liver and lactate from muscle

Question 18

What’s Different in Type 1 Diabetes

Answer 18

• A constant insulin supply from exogenous source is generally present
• Variable insulin absorption
• Suboptimal release of counter-regulatory hormones
• Increased skeletal muscle uptake following exercise
• Increased insulin sensitivity after exercise

Question 19

Exercise Physiology in Type 1 DM

Answer 19

Question 20

Preventing Hypoglycemia

Answer 20

Training diet
* Amounts and types of foods; (food matches doses in insulin)
* timing

Pre/During Sport:
* ExCarbs or
* Insulin reduction or
* Combination of both

Question 21

Tailored Advice for Athletes with DM

Answer 21

Know the athlete:
* Recreational or competitive/elite?

Type 1 versus Type 2 DM
* Type 2 DM is relatively rare in elite level athletes

Know the sport/activity: Aerobic versus anaerobic activity
* Risk for hypoglycemia with prolonged aerobic activity
* Risk for hyperglycemia with high-intensity anaerobic activity

Question 22

macronutrient adjustments in the training diet for those with diabetes

Answer 22

55-60% CHO
* (approx. 8 to 10 grams CHO/kg/day)
* Consistency is important If CHO stores (glycogen) drop off b/c not being
replenished, risk for hypoglycemia increases

25-30% Fat

12-15% PRO
* < 1 hour/day moderate activity = 0.8-1 g PRO/kg
* > 1 hour/day = up to 1.7 g PRO/kg

Question 23

Pre-Event Eating guidelines

Answer 23

Pre-event meal 3 to 4 hours prior to start of exercise which should contain CHO
* Ideally, a CHO containing beverage providing 1-2 g CHO/kg should be consumed 1 h prior to exercise if BG <5 mmol/L or trend is towards decreasing levels

Question 24

pre-exercise guidelines

Answer 24

• Assess the timing, mode, duration and intensity of exercise
• Eat a carbohydrate containing meal 1-3 hours prior to exercise
• Assess hydration status
• Assess metabolic control
• Assess Aerobic activity
• Assess Anaerobic activity

Question 25

Assessing the timing, mode, duration and intensity of exercise

Answer 25

High intensity and/or long duration exercise present greatest risk

Question 26

How much fluid should be taken in pre-exercise

Answer 26

At least 250 ml in 20 min prior to start of activity

Question 27

Assessing metabolic control

Answer 27

• If BG is < 5 mmol/L and decreasing, extra calories may be needed
• If BG is 5-13.9 mmol/L, extra calories may not be needed depending on the duration and individual response to exercise
• If BG is ≥14.0 mmol/L and urine or blood ketones are present, delay exercise until levels are normalized with insulin administration.

Question 28

Assessing Aerobic activity

Answer 28

Aerobic activity typically results in a decrease in BG levels.
* Insulin dosages may need to be decreased while CHO intake may need to be increased for long duration or moderate intensities
* CHO – if indicated by metabolic assessment, plan to give extra during exercise at rate of 1–1.5 g CHO/kg/h of estimated exercise time

Question 29

Assessing anaerobic activity

Answer 29

• Anaerobic activity can produce rapid and dramatic increases in BG levels
• Insulin dosages may need to be increased during anaerobic activity
• Insulin dosages may need to be increased during anaerobic activity

Question 30

Why does anaerobic activity result in a rapid rise in BG levels?

Answer 30

Can cause acute increases in catecholamine, FFA, and ketone body levels
* Psychological stress can have the same effect

Question 31

reccomendations during-exercise

Answer 31

• Monitor BG levels every 30 min
• Maintain adequate fluid intake
• If indicted by metabolic assessment, consume CHO at 20-30 min intervals
• 1 to 1.5 g CHO/kg/h for activity lasting more than 1 hour
• Assumes an adequate pre-event meal was consumed
• Maintain adequate fluid intake

Question 32

reccomendations for After Exercise/Competition

Answer 32

Replete liver and muscle glycogen stores by consuming complex CHO
* Should be started as soon as possible after the end of exercise
* Eat to match hunger and to maintain euglycemia
* Monitor BG levels

Question 33

signs and symptoms of hypoglycemia

Answer 33

• Early: hunger, irritability, drowsiness or confusion, rapid heart rate, sweating, dizziness, or loss of color, typically develops when the blood glucose is below 4.00 mmol/L
• Late: brain neuronal glucose deprivation occurs and causes blurred vision, fatigue, difficulty thinking, decreased motor control, aggressive behavior, seizures, convulsions, and loss of consciousness

Question 34

Prevention of hypoglycemia

Answer 34

• Frequent blood glucose monitoring
• Carb intake adjustment pre-exercise or fast acting carb supplement during exercise
• Insulin dose adjustments
• Avoid exercising during peak of insulin
• Prevent dehydration

Question 35

Treatment of hypoglycemia

Answer 35

• Check if they are alert and able to eat or drink without assistance
• Administer 15 g of fast acting carbs (4 Dex4 tabs, 15 gm sports gel, 4 oz juice or soda)
• Repeat glucose check every 15 min until blood glucose returns to normal range
• Once glucose is up, give complex carbohydrate snack (bagel, sandwich)
• If athlete is unconscious keep athlete on their side (hypoglycemia and glucagon can often cause nausea)
• Call 911

Question 36

Signs and symptoms of hyperglycemia

Answer 36

• Nausea, dehydration, decreased cognitive performance, decreased visual reaction time, sluggishness, fatigue
• Ketosis: Also may have rapid breathing, fruity odor to breath, unusual fatigue, sleepiness, inattentiveness, loss of appetite, increased thirst, and frequent urination

Question 37

prevention of hyperglycemia

Answer 37

• Frequent blood glucose monitoring
• Pre-exercise insulin dosage adjustments
• Frequent blood glucose testing

Question 38

Treatment of hyperglycemia

Answer 38

• Administration of small bolus of rapid acting insulin
• When blood glucose is ≥13.9mmol/L, test urine or blood for ketones; if ketones are moderate or high, exercise is contraindicated
• When blood glucose is ≥ 16.6 mmol/L no activity is allowed

Question 39

What is ExCarbs?

Answer 39

Extra Carbs for Exercise (ExCarbs)
* Goal: To match the amount of CHO the body will burn during activity to the amount of CHO taken in at fixed intervals during activity
* Think fuel injection!

Question 40

Methods for ExCarbs

Answer 40

• basic method
• semi-quantitative method
• quantitative method

Question 41

ExCarbs basic method

Answer 41

does not factor in known differences in exercise intensity and related rates of glucose disposal in muscle.
* 15 to 30 g “dose,” of CHO every 30 to 60 min of exercise.
* Athlete should monitor BG every 30 min and adjust ExCarb intake as needed.

Question 42

ExCarbs Semi-Quantitative Method

Answer 42

ExCarb “dose,” based on body mass.
* Based on an estimated glucose disposal rate into muscle of 1 g glucose/kg body weight/hour of activity (E.g. 55 kg women would supplement with 55 g of CHO every hour of activity)

Question 43

ExCarbs Quantitative Method

Answer 43

ExCarb “dose,” based on body mass AND type and intensity of activity.
* Published, standardized tables used to guide “dosing,” of ExCarbs.
* Assumes NO adjustments to insulin dosing for exercise.