Special Populations: Training for Female Athletes and Children

1. Special Populations: Training for Female Athletes and Children Powers CH 22

2. Males v. Females • Responses to training stimulus similar between genders • Special considerations for the female athlete: • Exercise and Menstruation • Eating Disorders • Bone Mineral Disorders • Exercise During Pregnancy

3. Exercise and Menstruation • Amenorrhea • Most common in distance runners, ballet dancers • Influencing factors: • Low % body fat?? • Increase in training stress / amount of training • Alteration of blood hormone concentrations modifies feedback to hypothalamus – may influence release of female reproductive hormones and alter menstrual cycle • Psychological stress related to training may alter blood levels of catecholamines and endogenous opiates, which may regulate reproductive system and menstrual cycle

4. Exercise and Menstruation • Dysmenorrhea (painful menstruation) • Incidence higher in training athletes • Related to prostaglandin (fatty acid) release just prior to menstrual flow • Associated pain (uterine ischemia) is increased with physical activity

5. Eating Disorders • Anorexia Nervosa • Psychological fear of fatness • Methods of weight “control” • Starvation, exercise, laxitives • Effects: • Excessive weight loss • Cessation of menstruation (amenorrhea) • Potentially fatal • Warning Signs: • Rapid weight loss • Excessive exercise • Mood swings • Avoiding food-related activities / pre-occupation with calorie intake, weight

6. Eating Disorders • Bullimia • Overeating (binge eating) followed by vomiting (purging) • May damage teeth, esophagus, stomach,… • Most bulimics are of normal BW • Warning Signs: • Noticeable weight loss? • Excessive concern about BW / self-criticism / depression • Strict diet followed by eating binges • Bathroom visits after meals

7. Eating Disorders • 50% of elite female athletes experience some type of eating disorder • Highest incidence: • Distance running • Swimming / diving • Figure skating • Gymnastics • Ballet • Body building

8. Bone Mineral Disorders • Major causes of bone mineral content loss (osteopenia): • Estrogen deficiency (due to amenorrhea) • Inadequate calcium intake (due to eating disorders)

9. Exercise During Pregnancy • Moderate intensity / short duration exercise OK in normal / healthy cases • Stress of pregnancy: • Blood volume increases 40-50% • O2 uptake slightly higher at rest / sub-max exercise • O2 cost of weight-bearing exercise increased • Higher HR at rest / sub-max exercise • CO higher at rest / sub-max exercise (1st 2 trimesters) Aquatic Programs – CV training that offers body support and accelerated heat transfer

10. Female Athlete Triad • Amenorrhea • “-” energy balance due to eating disorder and intense training • menstrual cycle “switched off” to conserve energy • Results in reduced estrogen production / blood estrogen levels • Estrogen prevents bone resorption / low levels = increased bone mineral loss • Eating Disorders • Low estrogen + calcium, Vitamin D deficiency = increased risk for bone mineral loss • Bone Mineral Loss

11. Sports Conditioning for Children • Cardiopulmonary system adaptations similar between children and adults under reasonable conditions of progressive increases in CP stress • Vigorous training does not appear to adversely affect musculoskeletal growth and development • A certain amount of physical activity is necessary for normal growth and development and may optimize development in children

12. Mechanical Stress • Growth cartilage • Epiphyseal plates • Closure varies bone-to-bone • All ossified (hardened with calcium) by age 18-20 • Articular cartilage • Apophysites

13. Mechanical Overload • Little Leaguers Elbow • Medial Humeral Epicondylitis • Humeral Supracondylar Fx

14. Mechanical Overload • Traction Apophysitis • Osgood-Schlatter’s Disease • Sever’s Disease • Slipped Capital Femoral Epiphysis

15. Influence of Training • Mechanical loading / “Pressure effects” of regular physical activity may stimulate bone growth to an optimal length • Excessive pressure: • Repetitive stress (excessive endurance training) or excessive overload (weight training) can retard linear growth • So how much is too much? • Program and stress level should approximate those encountered in sport • Intensity should not exceed 8-10 repetitions (~70% 1RM)

16. Exercise and Older Athletes • Max aerobic power decreases @ ~ 1% per year after age 20 • Decline in VO2 Max slowed by regular physical activity • Osteoporosis • 2-3 hours of physical exercise per week may reduce rate of expected bone mineral loss • Resistance training (esp. structural lifts) may have strong influence Middle-aged men showed ½ expected VO2 Max decrease over 20 year period Kasch et al., 1990

17. Effects of Training on Older Athletes • Endurance-trained (compared with sedentary): • Higher VO2 Max • Higher HDL / lower total cholesterol • Enhanced glucose tolerance / insulin sensitivity (“decreasing the need” = better control of blood glucose levels) • Greater muscle strength / quicker reaction time (lower risk of falling) “A Closer Look” 17.3 Powers CH 17, p352

18. Exercise for Special Populations: Diabetics, Asthmatics Powers CH 17

19. Diabetes • Blood sugar imbalance • Too little (hypoglycemia) • Too much (hyperglycemia) • Type I – Juvenile onset (<20 years) • 10% of diabetics • Type II – Adult onset (>40 years) • 90% of diabetics

20. Exercise and the Diabetic • Exercise increases rate at which glucose leaves blood • part of Tx for diabetic to regulate blood glucose levels • “control” of blood glucose levels - near normal - is essential during exercise • Lack of insulin = ketosis – metabolic acidosis resulting from accumulation of ketone bodies (short chain fatty acids) • Hyperglycemia and ketosis = Diabetic Coma • Hypoglycemia = Insulin Shock

21. Type I Diabetes • Primary concern w/ exercise = Avoid Hypoglycemia • Identify when changes in insulin or food intake are needed • Consume CHO as needed to prevent hypoglycemia • Make CHO foods readily available before, during, after • Quality pre-activity meal • Reduction in insulin injected on days of strenuous training • Learn how blood glucose responds to different types of physical activity

22. Type II Diabetes • Primary goals: • Control blood glucose • Deal with obesity • Exercise frequency = 4-7x per week • Promotes sustained increase in insulin sensitivity and facilitates weight loss / weight maintenance • Low intensity, long duration EX maximizes insulin sensitivity and weight loss effects and reduces hypertension and high cholesterol levels (raises HDL, lowers total cholesterol) • Strive to burn a minimum 1,000 kcal / week in physical activity

23. Asthma • Overproduction of mucous causes resistance to air flow on exhalation • Low maximal expiration corrected with bronchiodialator

24. Asthma • Extrinsic • Triggered by dust, chemicals, other irritants • Intrinsic • Influencing factors: • Type of exercise (running – esp. increased intensity / duration) • Time since previous bout of exercise • Interval since meds were taken • Temperature / humidity of inspired air

25. Mechanisms of Asthma • Irritants initiate asthma attack by increasing Ca++ influx into the mast cell lining bronchial tubes • Causes release of chemical mediators (histamines, leukotrines,…) • Triggers increased smooth muscle contraction (calcium-mediated) leading to bronchioconstriction (vagus nerve), inflammatory responses of tissue swelling and increased secretions into the airway

26. Management of Asthma • Medications • Cromolyn sodium and β-adrenergic agonists • Prevent entry of Ca++ into mast cell • Short duration exercise (< 5 min. duration / low to mod. intensity) • Warm up • Asthma meds taken prior to exercise • B-agonists carried, used as needed during exercise Dry air = primary trigger of attack (scarf or mask to trap moisture?)