Module 9 Lecture 1 Nutrition for Athletes with Diabetes Flashcards
Type I vs. type II diabetes
- 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%
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
pre-diabetes
Conditions of pre-diabetes
- 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.
Other Forms of Diabetes/Diabetic Symptomology
- 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
Health Benefits of Physical Activity for People with Diabetes
Reduced risk for:
* CVD
* Obesity and overweight
* Diabetes related co-morbidities (Neuropathy, Nephropathy)
Increased:
* Sense of well-being
* Control and self-efficacy
Effects of Physical Activity on Blood Glucose Control
- 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)
What is the goal of managing diabetes in athletes?
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
Diabetes Management – Type II Diabetes
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
how to manage T2D if being treated with insulin
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
Why is Type I diabetes more of an issue?
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
What exercise physiology normally happens in terms of serum glucose?
What are the counter regulatory hormones?
- glucagon
- growth hormone
- cortisol
- epinephrine
- norepinephrine
The net effect of these counter regulatory hormones is to maintain glucose homeostasis
Describe glucagon
(alpha cells in pancreas)
* Most efficient stimulator of gluconeogenesis
* Requires liver glycogen stores to acutely increase BG
Describe Growth Hormone
(anterior pituitary)
* Promotes lipolysis
* Increased hepatic glucose production
Role of cortisol
(adrenal cortex)
* Enhances gluconeogenesis
Role of epinephrine
(adrenal medulla)
* Inhibit insulin secretion
* Increase glucose secretion from liver and lactate from muscle
Role of norepinephrine
(adrenal medulla)
* Inhibit insulin secretion
* Increase glucose secretion from liver and lactate from muscle
What’s Different in Type 1 Diabetes
- 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
Exercise Physiology in Type 1 DM
Preventing Hypoglycemia
Training diet
* Amounts and types of foods; (food matches doses in insulin)
* timing
Pre/During Sport:
* ExCarbs or
* Insulin reduction or
* Combination of both
Tailored Advice for Athletes with DM
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
macronutrient adjustments in the training diet for those with diabetes
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
Pre-Event Eating guidelines
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
pre-exercise guidelines
- 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