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Introduction to the Chapter. Chapter Focus:physiological differences and similarities
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1. Ch 9 Physiology & Exercise Chapter by Carol L Christensen
In Women In Sport
Notes by N. Bailey
2. Introduction to the Chapter Chapter Focus:
physiological differences and similarities
& Other physiological concerns
3. Records Improving Performance records improving for both men and women
Women are closing the gap
For both aerobic capacity & speed events
Much overlap between the sexes
Look at data on page 180
4. Factors Affecting Performance Differences Hormonal differences ate menarche
Socio-cultural differences:
Clothing, activity level, lack of opportunities for women, lower monetary rewards
Social myths: women are more easily injured, media coverage that marginalizes women athletes, gender roles
5. Physiology & Performance Pre-puberty and Puberty
Aerobic Capacity
Anaerobic Capacity or Power
Muscle Strength and Physiology
Body Composition
6. Puberty 12 yrs: Average age of puberty for girls
Prior to that differences accounted for by differential training and skills, not physiology
Boys mature 2 3 years later
Mature male larger size due to increased length of growth period
7. Aerobic Capacity Females at a disadvantage de to smaller size (fewer rbc, lower hemoglobin concentration, smaller heart, lungs, and lower blood volume
15% to 25% disadvantage
Performance records demonstrate that this difference can be somewhat overcome with training and coaching
8. Anaerobic Capacity or Power Women have less muscle mass
And lower Anaerobic Power
AnT Anaerobic threshold is related to endurance performance.
The point where anaerobic energy sources are used at the cell site
When lactic acid accumulates
Women cant maintain as fast a pace
9. Strength No differences in muscle tissue itself
Differences in strength greater than that for anaerobic and aerobic power
Large overlap, but generally women have 66% of the strength of men
Upper body, 56% as strong as men
Lower body, 72% as strong
No Difference in fast and slow twitch
10. Body Composition Female athletes closer to male athlete counterparts than to untrained women
Average young woman 22 to 24% body fat
Average woman athlete 17 to 14%
Average 60 yr- old woman professor ?
Average untrained male: 14 16%
11. Response: Environment Conditions Temperature Regulation
Hot Environments
Cold Environments
Altitude
Air Pollution
12. Importance of Topic Various environments impose demands on the body during exercise
In extreme conditions all are affected
With moderate changes some people are affected and some are not
Responders experience symptoms with mild conditions v. Non-responders
13. Temperature Regulation Hyper- & hypothermia occurs in extreme temps & are life threatening
Exercise increases metabolism & therefore, heat
Okay in cold climate, a problem in hot
Hot environment: sweat 90% heat loss
14. Temperature Mechanisms Convection: wind blowing on body
Conduction: contact with colder or warmer surface
Radiation: heat transfer through electromagnetic waves
Evaporation of sweat that we mentioned in the last slide
15. Hot Environments Higher heart rate, higher sweat rate, increased glucose use for energy, increased blood flow to the skin
Responses help maintain temperature
Men & women with similar aerobic fitness levels respond similarly to heat
In extremes disadvantaged because of greater surface area to gain heat
16. Safety Precautions Heat stroke, exhaustion & dehydration
Drink plenty of fluids, especially water
Reduce intensity, duration
Avoid hottest part of the day
Acclimatization: reduced sweat rate,earlier onset, increase plasma volume takes about 14 days
17. Cold Environments Greater oxygen consumption during sub-maximum work
Increased glucose use for energy
Less blood flow to the skin
Hypothermia and frostbite
Dress in layers, dry clothing, protect the hands and the head
18. Different Responses? In general, similar physiological responses
Women at greater risk: greater surface area relative to body mass helps cool
Less muscle mass produces less heat
With proper precautions both men and women withstand cold temperatures
19. Altitude Low level of oxygen=hypoxia
Higher heart rates, increased ventilation, reduced aerobic power
Endurance performance is impaired
Adaptations: 4 to 6 months
Increases in hematocrit, hemoglobin, myoglobin and rbc attenuates hypoxia
20. Air Pollution At high levels: chest tightness, difficulty deep breathing, eye irritation, headaches, dry throat
Endurance performance impaired by high carbon dioxide
Smog alerts: exercise indoors, avoid car exhaust
Men and women affected equally
21. Responses To Training Virtually the same for all individuals
Altered by environmental conditions & substances like drugs & alcohol
Increases in heart rate, cardiac output,
ventilation, and metabolism
* When fitness levels are similar no sex differences
22. General Response Regular program of exercise results in increased VO2 Max, strength, power and speed.
Type of training influences type of response specificity principle
Training programs should be based on capacities, skills and abilities, not sex
Men will gain more than women
23. Specific Training Responses Training depends upon particular stressors. For example:
Yoga for strength and flexibility
Weight training for strength & loss of body fat
For Strength increase resistance
For endurance increase reps
24. For Strength and Endurance Lift 2 to 3 days per week
Do at least one set of 8-12 repetitions
Choose a weight that causes fatigue at the end of the last repetition
Better to underestimate the weight at first in order to prevent muscle injury
25. Gender Differences Womens earliest strength increase result of increased muscle fiber recruitment
Mens earliest increase due to increase in muscle fiber size
After several weeks of training women also experience hypertrophy
26. Anaerobic Training Interval training for 50 to 400 meter runs
Timing of the work and rest intervals determines the specific training result
For most running games require both aerobic and anaerobic training
Wind sprints= anaerobic + aerobic training needed for running games
27. Stretching Never stretch a cold muscle
Warm up by walking, jogging before stretching
Static stretch better than ballistic
Stretch the muscle until slight tension is felt, not pain. Hold for 15 to 60 seconds
No evidence of injury prevention
28. Warming Up & Cooling Down Gradual adjustment to increase demands of exercise: oxygen delivered to muscle cells, decreased time for muscle contraction
Do low intensity activity similar in nature to the workout activity
Cool down same activity only less intensity. Best time to stretch
29. Special Physiological Concerns Menarche
Menstruation
Menopause
Pregnancy
Osteoporosis
Injuries
30. Menarche Training at young age may delay onset of puberty or maybe not
Trained females begin menstruation from .5 to 2.5 years later
No evidence that delay is harmful in any way
Early maturing girls may drop out of sport so we find these data
31. Menstruation Research results unclear about effects on performance
Individual variability obscures any patterns of performance.
Some evidence suggests that regular exercise decreases incidence and severity of painful menstrual periods
32. Menstrual Disruption Higher incidence of menstrual disruption in younger, highly motivated athletes, in intensively trained athletes, and in sports that emphasize lean body type
Amenorrhea related to osteoporosis
Female Athletic Triad also a concern
33. Menopause A drop in circulating hormones, especially estrogen
Hot flashes not harmful
Not much studied
No difference in ability to improve fitness levels
Exercise recommended for fat control & delay effects of aging
34. Pregnancy Increased blood volume, cardiac output, fat and weight distribution, changes in most systems
No difference between athletes and non-athletes in major disorders
Athletes shorter periods of labor and fewer complications
35. Recent Research Exercising pregnant women have higher ventilation volumes, higher ratings perceived exertion, energy expenditure
Dont do maximum effort
High risk pregnancy avoid exercise
Most benefit from exercise: 3days per week; non-weight bearing
36. Osteoporosis 4 times more likely in women
Three major risk factors: low estrogen, low calcium, lack of physical activity
Prevention should start in the teen years
ERT recommended
Low impact exercises
37. Injuries In most activities no difference in injury rates
Anterior cruciate ligament injuries the exception to this rule
Difference in injury rate probably not related to anatomy
Prevention and rehabilitation methods the same; get into good shape