1. Training Considerations for Special Populations

2. Chapter OBJECTIVES
Understand that not everyone should be presented with the same exercise stimulus.
Describe the physiological differences that exist between men and women that might affect exercise prescription.
Discuss the limitations that pregnancy might place on a woman’s capacity to exercise safely.
Describe what factors must be considered when designing exercise programs for children and older adults.

3. Introduction to Sex Differences in Sport and Exercise
For decades, culture, athletic governing bodies, and PE curricula perpetuated the myth that girls and women should not compete in sport
Last 30 to 40 years, girls and women have achieved great athletic feats
Sex differences in performance still exist
Separating biological versus other factors

4. Body Size and Composition
Testosterone leads to
–  Bone formation, larger bones
–  Protein synthesis, larger muscles
–  EPO secretion,  red blood cell production
Estrogen leads to
–  Fat deposition (lipoprotein lipase)
Faster, more brief bone growth
Shorter stature, lower total body mass
–  Fat mass, percent body fat

5. Physiological Responses to Acute Exercise
Muscle strength differs between sexes
Upper body: women 40 to 60% weaker
Lower body: women 25 to 30% weaker
Due to total muscle mass difference, not difference in innate muscle mechanisms
No sex strength disparity when expressed per unit of muscle cross-sectional area

6. Physiological Responses to Acute Exercise
Cardiovascular function differs greatly
For same absolute submaximal workload
Same cardiac output
Women: lower stroke volume, higher HR (compensatory)
Smaller hearts, lower blood volume
For same relative submaximal workload
Women: HR slightly , SV , cardiac output 
Leads to  O2 consumption

7. Physiological Responses to Acute Exercise
Women compensate for  hemoglobin via  (a-v)O2 difference (at submaximal intensity)
(a-v)O2 difference ultimately limited, too
Lower hemoglobin, lower oxidative potential
Sex differences in respiratory function
Due to difference in lung volume, body size
Similar breathing frequency at same relative workload
Women  frequency at same absolute workload

8. Physiological Responses to Acute Exercise
Women’s VO2max < men’s VO2max
Untrained sex comparison unfair
Relatively sedentary nonathlete women
Relatively active nonathlete men
Trained sex comparison better
Similar level of condition between sexes
May reveal more true sex-specific differences

9. Physiological Adaptations to Exercise Training
Body composition changes
Same in men and women
–  Total body mass, fat mass, percent body fat
–  FFM (more with strength vs. endurance training)
Weight-bearing exercise maintains bone mineral density
Connective tissue injury not related to sex

10. Physiological Adaptations to Exercise Training
Strength gains in women versus men
Less hypertrophy in women versus men, though some studies show similar gains with training
Neural mechanisms more important for women
Variations in weight lifted for equivalent body weight
For given body weight, trained men have more FFM than trained women
Fewer trained women
Factors other than FFM?

11. Physiological Adaptations to Exercise Training
Cardiorespiratory changes not sex specific
Aerobic, maximal intensity
–  Qmax due to  SVmax ( preload, contractility)
–  Muscle blood flow, capillary density
–  Maximal ventilation
Aerobic, submaximal intensity
Q unchanged
–  SV,  HR

12. Physiological Adaptations to Exercise Training
VO2max changes not sex specific
~15 to 20% increase
–  Qmax,  muscle blood flow
Depends on training intensity, duration, frequency
Lactate threshold 
Blood lactate for given work rate 
Women respond to training like men do

13. Effect of Menstruation on Performance
No reliable data indicate altered athletic performance across menstrual phases
No physiological differences in exercise responses across menstrual phases
World records set by women during every menstrual phase

14. Female Athlete Triad
Amenorrhea
Osteoporosis
Disordered Eating

15. Female Athlete Triad Syndrome of interrelated conditions
Energy deficit  secondary amenorrhea  low bone mass
Disordered eating may (not) be involved
Three disorders can occur alone or in combination, must be addressed early
Treatment:  caloric intake,  activity (in some cases)

16. Pregnancy Recommendations
Moderate exercise 3x/week
Reduces T3DM risk
Resistance training recommended
Ensure adequate caloric intake
No supine exercise after first trimester
Non-weight-bearing exercise preferable
No risk of falling, loss of balance, etc.
Decrease vigorous exercise in third trimester

17. Children and Exercise
Historic reflections on exercise and resistance training outdated
Cardiovascular differences
↓ heart size, ↑ HR both at rest and during ex
Limited anaerobic energy supply
↓ blood lactate
↓ glycolyic enzymes
Hyperthermia risk ↑ due to less efficient sweat mechanism

18. Children and Exercise

19. Older Adults and Exercise
↓ in physiological capacity is inevitable
“Psychomotor Slowing”
Cardiovascular
↓ in Q, SV, HRmax, VO2max, a-vO2 diff
Sarcopenia - Skeletal muscle loss results in ↓ isometric and dynamic muscle strength
Apoptosis
Bone mineral density ↓

20. Older Adults and Exercise
Baseline assessment for everyone
Aerobic prescription – 150+ minutes of moderate aerobic activity/wk
Resistance exercises on 2 or more days a week that work all the major muscles (1s, 10-15r).