1. Chapter 17 Exercise for Special Populations
EXERCISE PHYSIOLOGY
Theory and Application to Fitness and Performance, 6th edition
Scott K. Powers & Edward T. Howley
Presentation revised and updated by
Brian B. Parr, Ph.D.
University of South Carolina Aiken

2. Diabetes
Characterized by an absolute (type 1) or relative (type 2) insulin deficiency that results in hyperglycemia
A major health problem and leading cause of death in the United States
More than 18.2 million have diabetes
Only 11.1 million are diagnosed
Warning signs:
Frequent urination/unusual thirst
Extreme hunger
Rapid weight loss, weakness, and fatigue
Irritability, nausea, and vomiting

3. Diabetes Type 1 Type 2 Lack of insulin Develops early in life
Dependent on exogenous insulin
Develops early in life
Associated with viral infections
5–10% diabetic population
Type 2
Resistance to insulin
Develops later in life
Associated with upper-body obesity
90–95% diabetic population

4. Characteristics of Type 1 and Type 2 Diabetes
Table 17.1

5. Exercise and the Diabetic
Control of blood glucose is important
Adequate insulin is required
Ketosis
Metabolic acidosis from accumulation of ketone bodies
May result from a lack of insulin

6. Effect of Prolonged Exercise in Diabetics
Figure 17.1

7. Exercise and Type 1 Diabetes
Metabolic control before physical activity
Avoid exercise if fasting glucose is >300 mg/dl (or >250 mg/dl with ketosis)
Ingest carbohydrates if glucose is <100 mg/dl
Blood glucose monitoring before and after exercise
Identify when changes in insulin or food intake is needed
Learn how blood glucose responds to different types of exercise
Food intake
Consume carbohydrates to prevent hypoglycemia
Carbohydrates should be readily available during and after exercise

8. Effect of Plasma Insulin Levels in Type 1 Diabetics During Exercise
Figure 17.2

9. Exercise Prescription for Type 1 Diabetes
Exercise 20–60 min, 3–4 days per week, 50–85% heart rate reserve
May use non-weight bearing, low-impact activities
If weight-bearing activities are contraindicated
Use lighter weights (40–60% 1RM), 15–20 reps
Avoid the Valsalva maneuver
Heavier weights for athletes
Drink extra fluids and have carbohydrates available
Exercise with someone in case of emergency

10. Exercise and Type 2 Diabetes
Exercise is a primary treatment
Help treat obesity
Help control blood glucose
Combination of diet and exercise may eliminate need for drug treatment
Exercise prescription
Dynamic aerobic activity at 50–90% HRmax
20–60 min, 4–7 times/week
Strength training is also recommended
Goal to expend a minimum of 1,000 kcal/week
May need to reduce dosage of medications to maintain blood glucose

11. American Diabetes Association Goals for Nutrition Therapy
Attain and maintain optimum metabolic outcomes to reduce risk of complications
Blood glucose in normal range
Improved lipid and lipoprotein profile
Lower blood pressure
Prevent and treat chronic diabetes complications
Improve health through healthy food choices and physical activity
Address individual nutritional needs

12. Prevention or Delay of Type 2 Diabetes
Impaired fasting glucose (IFG)
Fasting BG 100–125 mg/dl
Impaired glucose tolerance (IGT)
Oral glucose tolerance test
2-hour blood glucose 140–199 mg/dl
Prediabetes
Having IFG or IGT
Likely to develop type 2 diabetes
150 min/week of physical activity and losing 5-10% of body weight reduces risk
Better approach than using drugs

13. Asthma
A respiratory problem characterized by a shortness of breath accompanied by a wheezing sound
Due to:
Contraction of smooth muscle of airways
Swelling of mucosal cells
Hypersecretion of mucus
20 million are affected by asthma
1.9 million emergency room visits
4,000 deaths
Direct and indirect costs of $16.1 billion

14. Asthma: Diagnosis and Causes
Diagnosed using pulmonary-function testing
Low maximal expiratory flow rate
Triggers
Dust, chemicals, antibodies, exercise
Causes influx of Ca+2 into mast cells
Release of chemical mediators that cause:
Increased smooth muscle contraction leading to bronchoconstriction
Bronchoconstrictor reflex via vagus nerve
Inflammatory response

15. Proposed Mechanism by Which an Asthma Attack Is Initiated
Figure 17.3

16. Prevention and Relief of Asthma
Avoidance of allergens
Immunotherapy
Medications
Cromolyn sodium
2-agonists
Theophylline
Corticosteroids
Leukotriene inhibitors

17. Exercise-Induced Asthma
More common in asthmatics
Does not necessarily impair performance if controlled
Caused by drying of respiratory tract
Increases osmolarity on surface of mast cell
Triggers Ca+2 influx and airway narrowing
Reducing the chance of an attack
Warm-up
Short-duration exercise
Treatment
-agonist in case of attack during exercise
Other medications to prevent attack

18. Chronic Obstructive Pulmonary Disease (COPD)
Includes chronic bronchitis, emphysema, and bronchial asthma
Can create irreversible changes in the lung
Can severely limit normal activities
Testing for COPD
FEV1
Graded exercise test
VO2max
Maximal exercise ventilation
Changes in arterial PO2 and PCO2

19. Treatment of COPD Goals: Treatments: Outcomes:
Reduced reliance on O2 and medications
Improved ability to complete daily activities
Treatments:
Medications (including supplemental O2)
Breathing exercises
Dietary therapy
Exercise
Counseling
Outcomes:
Increased exercise tolerance without dyspnea
Increased sense of well-being

20. Hypertension Classifications: Normal <120/<80 mmHg
Prehypertension 120–139/80–89 mmHg
Hypertension (stage I) 140–159/90–99 mmHg
Recommendations
Lose weight if overweight
Limit alcohol intake
Reduce sodium intake
Maintain adequate dietary K+, Ca+2, Mg+2
Stop smoking
Reduce dietary fat, saturated fat, and cholesterol intake

21. Exercise for Hypertension
Exercise can be used as a non-drug treatment
Recommendations:
Moderate intensity exercise (40–60% HR reserve)
30 minutes on most, preferably all, days
Goal of expending 700–2000 kcal/week
ACSM recommendation for improving VO2max can also be followed
Precautions
Blood pressure should be monitored for those on medications

22. Cardiac Rehabilitation: Patient Population
Those who have or have had:
Angina pectoris
Chest pain due to ischemia
Myocardial infarction (MI)
Heart damage due to coronary artery occlusion
Coronary artery bypass graft surgery (CABGS)
Bypass one or more blocked coronary arteries saphenous vein or internal mammary artery
Angioplasty (PTCA)
Balloon tipped catheter used to open occluded arteries
May insert a stent to keep artery open

23. Cardiac Rehabilitation: Medications
b-blockers
Reduce work of the heart
Anti-arrhythmics
Control dangerous heart rhythms
Nitroglycerine
Reduce angina symptoms

24. Cardiac Rehabilitation: Testing
Graded exercise testing
ECG monitoring (12-lead)
Heart rate and rhythm
Signs of ischemia (ST segment depression)
Blood pressure
Rating of perceived exertion (RPE)
Signs or symptoms
Chest pain
May include radionuclide imaging
Evaluate perfusion (201Thallium)
Evaluate ventricular ejection (99Technetium)

25. Cardiac Rehabilitation: Exercise Programs
Exercise prescription
Based on GXT results
MET level, heart rate, signs/symptoms
Whole body, dynamic exercise
Intensity, duration, and frequency based on severity of disease
Effects
Increased functional capacity (VO2max)
Reduced signs/symptoms of ischemia
Improved risk factor profile

26. Exercise For Older Adults
VO2max declines ~1% per year
Regular exercise may reduce rate of decline
Benefits of participation
Improved risk factor profile
Increased strength and VO2max
Increased bone mass
Recommendations
Similar to younger subjects
Medical exam and risk factor screening is essential

27. Exercise and Bone Health
Osteoporosis results in reduced bone mineral density and increased fracture risk
More common in women over fifty due to lack of estrogen
Prevention and treatment
Dietary calcium
>1000 mg/day through food and supplements
Hormone replacement therapy (HRT)
Prevents bone loss and reduces fracture risk
May increase risk of cardiovascular disease and cancers
Exercise
Weight-bearing activities and resistance training
2–3 hours per week

28. Exercise During Pregnancy
Regular endurance exercise poses no risk to the fetus and is beneficial for the mother
Recommendations
Pregnant women should consult their physician prior to beginning any exercise program
Absolute and relative contraindications
Follow ACSM/CDC recommendation
30 min/day of moderate-intensity activity on most, preferably all, days
Intensity determined by:
Heart rate, Rating of perceived exertion, or “talk test”
No supine exercise after first trimester