Women in Sports: Historical Context

Exercise Physiology I - AS24

• Course title for the subject of exercise physiology
• Focused on sex-specific aspects in exercise, training, and performance

Learning Objectives

• Students can name past reasons for women not being permitted to participate in sports
• Students can critically evaluate the topic of sex versus gender in sports
• Students can discuss physiological differences and mechanisms associated with performance levels in various sports
• Students can discuss sex-specific differences in response to training
• Students can discuss sex-specific effects that might elevate injury risk in women
• Students can critically evaluate issues connected to training and performance, such as the menstrual cycle, contraceptives, pregnancy, pelvic floor, and RED-S (Relative Energy Deficiency in Sports) or empowerment

Differences between girls and boys

• Testosterone:
  • Higher levels in males contribute to larger bone structure and muscle growth.
  • Spurs protein synthesis and EPO (Erythropoietin) secretion, impacting red blood cell production.
• Estrogen:
  • Leads to faster, shorter bone growth in females.
  • Associated with lower overall body mass and distinct fat deposition patterns (particularly at the hips and thighs).
  • Affects lipoprotein lipase distribution differently.

Sex versus gender

• Sex: Biologically determined traits (physiological, genetic, and biological) defining a person as male, female, or intersex.
• Gender: Culturally and socially determined aspects shaping a person's identity and self-representation as male, female, or non-binary.
• The concepts of sex and gender aren't strictly binary. Genetic factors and biological structures can create a spectrum, encompassing a variety of male and female characteristics.
• People might identify as a different gender than their assigned sex, whether or not they have undergone gender affirmation surgery.

"Ancient" viewpoints on women in sports

• Historical views often depicted women as physically weaker and thus unsuitable for certain sports, sometimes discouraging participation in sports like long-distance races.
• Strength training was potentially restricted, as testosterone was thought to be essential for muscle development.

1967 - First women to finish the Boston Marathon

• K.V. Switzer achieved this feat.
• Prior to 1972, Women were not officially allowed to compete in the Boston Marathon, but eventually, 1984 marked their participation in the Olympics.

Women at the Olympic Games

• Women's participation in the Olympic Games has increased drastically over time, growing significantly from the start of the 20th century and onwards.
• Specific sports and disciplines where women's participation initially began are documented.

Finish times over years

• Historical data demonstrates a narrowing gap in finishing times across various distances, highlighting improved performance in women's sporting events.

Physiological sex differences

• Women often display 25-30% weaker lower body strength than men. Even when judged relative to body weight or fat-free mass, the difference in strength remains a consistent 5-15%.
• Women demonstrate 40-60% less upper body strength than men, potentially because of differences in muscle distribution and arm usage patterns.

Sex differences in muscular properties

• Studies have indicated differences in the relative abundance of different muscle fiber types between men and women.
• Quantitative analysis of muscle fiber distribution.

Sex differences in muscular properties (2)

• The study method employed in conducting a meta-analysis encompassing 110 different studies on muscle fiber types.
• Different methods employed, from histochemistry to electrophoresis.

Sex differences in muscle strength

• Maximum torque in knee extension is demonstrably stronger in men compared to women.
• Maximum torque in elbow flexion, like that seen in knee extension, displays demonstrable differences between women and men.
• Relative strength per unit of muscle mass, however, presents a less marked disparity compared with the absolute values for strength.

Sex differences in strength training

• Relative changes in strength gains are comparable between men and women.
• Both men and women exhibit similar improvements in strength following training.

Sex differences in fatigue resistance

• Women tend to exhibit greater resistance to fatigue during isometric contractions compared with men.

Sex differences in cardiorespiratory function

• Heart rate, stroke volume, and cardiac output are often similar.
• Differences primarily stem from the smaller heart and blood volume of women.

Maximal ventilation

• Age-dependent changes in maximal ventilation are observed in both male and female athletes.

Maximal oxygen consumption (VO2max)

• Differences include smaller muscle mass, larger body fat, smaller cardiac capacity, lower plasma volume, and lower hemoglobin concentration in women, which can contribute to lower VO2max values, although some variation and interplay are present.

Cardio respiratory adaptations to training

• Aerobic adaptations, including maximal intensity responses, maximal ventilation, and submaximal intensity responses, show no significant sex-specific differences.

Women Athletes

• Focus Areas:
  • Menstrual cycle
  • Contraceptives
  • RED-S (Relative Energy Deficiency in Sports)
  • Pregnancy
  • Pelvic floor
  • Empowerment

Effects of Menstrual Cycle Phase on Exercise Performance

• Performance might marginally decrease during the early follicular phase compared with other phases.
• Huge variation among studies, demonstrating a need for higher quality research.

Elite Athlete Performance

• Menstrual cycle's impact on performance parameters is unclear.
• Large studies for individualization in training are needed.

What do athletes, medical doctors, and trainers say?

• A wide array of opinions and experiences are expressed regarding training and performance management in athletes, particularly those of women, acknowledging the importance of individual needs.

Menstrual dysfunction in athletic women

• Definitions:
  • Eumenorrhea: normal cycle
  • Oligomenorrhea: less frequent or irregular menstrual periods
  • Amenorrhea: absence of menstruation
• Effects:
  • Menstrual dysfunction is more common in athletes with lean physiques (5–66%).
  • Dysfunction does not equate to infertility.

Potential causes discussed (since 1970) of menstrual dysfunction in athletic women

• History or previous menstrual irregularities
• Acute stress
• Heavy training volume
• Low body weight/fat percentage
• Hormonal imbalance

Relative Energy Deficiency in Sports (RED-S)

• A systemic consensus statement on relative energy deficiency in sports.

Pregnancy - Exercise Recommendations

• Considerations
  • Stop activity when fatigued or uncomfortable.
  • Adequate caloric and hydration intake.
  • Cautious ramping up of exercise after childbirth.
• Precautions
  • Activities with risk of falling or loss of balance are less suitable.
  • Avoid supine positions after the first trimester.
• Additional precautions: Scuba diving is also not recommended.

Pelvic floor (dys)function

• Structure and function: Composed of muscles, fascia, and ligaments. It provides support to internal organs and maintains continence.
• Dysfunction: Can arise from too much or too little tension, affecting urinary or bowel function, and causing pain.
• Specific training: Exercises for strengthening and relaxing the pelvic floor muscles are available.

Sport, contraceptives, and cycle-adapted training

• Hormonal and non-hormonal contraceptives and cycle-adapted training are mentioned.
• Detailed guidance is provided in resources (including links).

Menstrual Dysfunction in athletic women (RED-S)

• This describes a triad of menstrual disturbances, low bone mineral density, and low energy availability in female athletes.

Overview of Eating Disorders

• Two main eating disorders in athletes and others:
  • Anorexia nervosa
  • Bulimia nervosa
  • Both involve a distorted body image and detrimental eating habits, potentially leading to major health risks.

Osteoporosis and RED-S

• Role: Bone loss is a critical concern related to energy deficiency disorders.
• Reduced bone mineral content and microarchitecture are risk factors, especially after menopause.
• Prevention: Engaging in weight-bearing exercises is helpful in slowing down this bone mineral loss.

Exercise in pregnancy

• Risks in pregnancy due to exercise are also discussed.