Exercise Physiology I - Sex-Specific Aspects (PDF)

Department of Health Sciences and Technology Institute of Human Movement Sciences and Sport Hier steht der Titel der Präsentation Exercise Physiology I – AS24 Dieser kann, wenn immer nötig, über zwei oder sogar drei Zeilen laufen Sex-specific aspects in exe...

Department of Health Sciences and Technology Institute of Human Movement Sciences and Sport Hier steht der Titel der Präsentation Exercise Physiology I – AS24 Dieser kann, wenn immer nötig, über zwei oder sogar drei Zeilen laufen Sex-specific aspects in exercise, training and performance Prof. Dr. Beat Muster Prof. Dr. Beat Muster Funktion des Präsentierenden Funktion des Präsentierenden TT. Monat JJJJ, Ort TT. Monat Prof. JJJJ,M.Ort Christina Spengler, PhD, MD Learning Objectives Students are able to name reasons purported earlier for women not being able or allowed to do sports critically reflect on the topic of sex vs. gender in sports discuss physiological differences and mechanisms associated with different levels of performance in different types of sports discuss sex-specific differences in response to training discuss sex-specific effects that might put women at a higher injury risk critically reflect on specific issues associated with training and performance, e.g. menstrual cycle, use of contraceptives, pregnancy, pelvic floor, RED-S, empowerment Exercise Physiology I - Sex-specific aspects in exercise, training and performance 2 Differences between girls and boys from children to adults Testosterone é Bone formation à larger bones é Protein synthesis à larger muscles é EPO secretion, é red blood cell production Estrogen Faster and briefer bone growth à shorter stature, lower total body mass é Fat deposition at hip/thigh (lipoprotein lipase distribution different) é Fat mass, é % body fat Exercise Physiology I - Sex-specific aspects in exercise, training and performance 3 Sex versus gender in (sports) science For a long time (and sometimes still), the terms sex and gender were used interchangeably in literature. With respect to research on differences between females vs. males – women vs. men, a definition - Sex: Biologically determined, i.e. physiological, genetic, and biological traits that define a human as being male, female or intersexual - Gender: Culturally determined, i.e. social, cultural, and psychological influences that construe an individual’s self-representation as male, female, or non-binary. But - the concept of sex itself is not dichotomous: - Genetic determinants of sex and biological structure and function can create a spectrum of male or female trait characteristics - Individuals with the structural and functional characteristics of a male (or female) may identify and live as a woman (or man), with or without having undergone surgical transformation. Exercise Physiology I - Sex-specific aspects in exercise, training and performance 4 Katharina von Salis Professor in the Micropaleontology Group of the Geological Institute at ETHZ. Working for the Office of Equal Opportunity at ETH and retired in 2001. Exercise Physiology I - Sex-specific aspects in exercise, training and performance 5 "Ancient" viewpoints regarding women in sports Uterus may fall out during intense sport Girls are weak, thus not suited for exercise and competition, thus … à Physical education needs to be different: less strenuous training, no long-distance runs à No strength training (possible) because testosterone is needed for strength gains Sex-specific differences in joint integrity and laxity, strength of ligaments, tendons and bones à Risk of more injuries No sports in pregnancy Exercise Physiology I - Sex-specific aspects in exercise, training and performance 6 1967– K.V. Switzer, the first women to finish Boston Marathon (enrolle/dressed as man) ≥ 1972 (5y later) women were officially allowed to participate ≥ 1984 women could compete at Olympics in marathon "Get the hell out of my race and give me those numbers" says race director. C. M. http://www.npr.org/blogs/thetwo-way/2012/04/02/149876890/photo-the-first-woman-to-enter-the-boston-marathon Spengl er, Exerci 7 se Exercise Physiology I - Sex-specific aspects in exercise, training and performance Physio logy Lab  Women at Olympic Games 1st women athlete on Time Magazine 1924 Edith Cummings Women (% of all participants) Mrs Kussin and Mrs Edwards , Marathon boxing, 1912 Year en.wikipedia.org Exercise Physiology I - Sex-specific aspects 8 in exercise, training and performance 8 Finish times over years – males and females Wipp & Ward, Nature, 1992 Exercise Physiology I - Sex-specific aspects 9 in exercise, training and performance 9 Physiological sex differences Females have / are on average … 25 to 30% weaker in lower body (mainly lower extremities), but expressed … relative to body weight à only 5-15% weaker relative to fat free mass (FFM) à no difference in strength 40 to 60% weaker in upper body (thorax, abdomen, arms) also when expressed … relative to body weight or total FFM à differences persists possibly because of different muscle mass distribution between males and females different arm use pattern (men use arm more) Exercise Physiology I - Sex-specific aspects in exercise, training and performance 10 Sex differences in muscular properties For comparison Type I Type IIA Type IIB (now Type IIX) Review of 19 studies 46 ± 15% 39 ± 12% 15 ± 9% Men (n=215) 64 ± 1 (40 – 80) years 4'591 µm2 4'958 µm2 4'439 µm2 Men (n = 267) Women (n =1 56) Type I 50.3% no significant m/w - difference à m+w pooled 51 ± 13% * 37 ± 10% 12 ± 9% * Women (n=203) 4'044 µm2 * 3'594 µm2 * Cross sectional area 2'837 µm2 * men: 4'329 ± 193 µm2 women: 3'447 ± 155 µm2 (significant difference, p < 0.01) parts of Mm. serrati Exercise Physiology I - Sex-specific aspects in exercise, training and performance Men: 24±4 (17-33) years old Simoneau et al. Am J Physiol, 1989 Gouzi et al., J Appl Physiol, 2013 Women: 23±3 (16-31) years old Sex differences in muscular properties Clinical Anatomy. 2024;37:81–91 A study was eligible for inclusion if the following conditions were met: data were published in a journal paper the paper was published in English muscle biopsies were performed on living humans muscle fiber percent distribution or percent area data were reported mean values of muscle fiber percent distribution or percent area were reported for both men and women Common reasons for exclusion included: data acquired at autopsy data not segregated by sex or only men or women no data on fiber percent distribution No data on percent area an unconventional Meta-Analysis – still likely the largest dataset (106 studies 1976 – 2022 in Meta-Analysis) Exercise Physiology I - Sex-specific aspects in exercise, training and performance Sex differences in muscular properties Clinical Anatomy. 2024;37:81–91 Fiber typing Earlier: mATPase (myofibrillar adenosine triphosphatase) histochemistry: à Type I, Type II, IIA, IIX (in earlier papers IIB) Later: immunohistochemistry and SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis) à Myosin heavy chain (MHC) isoform content: MHC I, MHC IIA, and MHC IIX With strong correlations between proportional representations of MHC I, MHC IIA, and MHC IIX isoforms and proportional representations of Type I, Type IIA, and Type IIX fibers. Exercise Physiology I - Sex-specific aspects in exercise, training and performance Sex differences in muscular properties Clinical Anatomy. 2024;37:81–91 Exercise Physiology I - Sex-specific aspects in exercise, training and performance Sex differences in muscular properties Clinical Anatomy. 2024;37:81–91 Effect size (Hedges g): Positive: The characteristic is higher in men than in women. Negative: The characteristic is higher in women than in men. Magnitude of g: Small effect: ∣g∣ ≈ 0.2 Small but meaningful difference between men and women. Medium effect: ∣g∣ ≈ 0.5 Moderate difference between men and women. Large effect: ∣g∣ ≈ 0.8 or higher Substantial difference between men and women. Exercise Physiology I - Sex-specific aspects in exercise, training and performance Sex differences in muscular properties Nuzzo (2024): women (n = 2452) vs. men (n = 2875) in 110 studies (spe: though only 106 studies in meta-analysis) Smaller CSA for all muscle fiber types Smaller area (%) for Type II muscle fibers (spe: solid evidence?) Larger Type I/II fiber area ratios Age-dependence of % Type I fibers? Girls < Boys [Nuzzo 2024] Women > Men (middle age) [Nuzzo 2024]; 24 ± 4 (16 - 33) years [Simoneau et al., 1989] Women = Men ( > 59 years) [Nuzzo 2024] ; 64 ± 1 (40 - 80) years [Gouzi et al., 2013 Physiological explanation? What about strength and power? What about 'trainability'? Exercise Physiology I - Sex-specific aspects in exercise, training and performance Sex difference in muscle strength yes or no? à similar force per "unit of muscle" Exercise Physiology I - Sex-specific aspects in exercise, training and performance 17 Sex differences in muscular properties Summary: Women have / are … Not weaker relative to "muscle size" (CSA * height) à similar force per "unit of muscle" ( Exercise Physiology I - Sex-specific aspects in exercise, training and performance 18 Sex difference in ∆CSA with strength training? yes or no? men and women which are which? why? MRI-Slices of quadriceps muscle before / after 9 weeks of strength training 3x / wk - 5 sets / session sets were: 1. 5x @ 50% 1-RM 30s rest 2. 5x @ current 5-RM 90s rest 3. 5x @ current 5-RM + 5 lower 150s rest 4. 5x @ current 5-RM + 10 lower 180s rest 5. 5x @ current 5-RM + 15 lower Exercise Physiology I - Sex-specific aspects in exercise, training and performance Tracy et al., JAP, 1999 19 Sex difference in strength grain? Men Women Comparison of % change +27% ns +29% +13% ns +7% +10% ns +12% à relative changes were similar ! Tracy et al., JAP, 1999 Exercise Physiology I - Sex-specific aspects in exercise, training and performance 20 Sex difference in strength grain? Men Women Women Comparison Men % change +12% ns +12% +14% ns +16% +2% ns ns +8% ns +10% à relative changes are similar ! Tracy et al., JAP, 1999 Tracy et al., JAP, 1999 Exercise Physiology I - Sex-specific aspects in exercise, training and performance 21 Sex Differences in Resistance Training: A Systematic Review and Meta-Analysis Sex-Difference in relative changes: - Hypertrophy - none - Upper body strength - yes - Lower body strength - none Roberts et al., JSCR, 2020 Exercise Physiology I - Sex-specific aspects in exercise, training and performance 22 Sex Differences in Resistance Training: A Systematic Review and Meta-Analysis Roberts et al., JSCR, 2020 Exercise Physiology I - Sex-specific aspects in exercise, training and performance 23 Sex Differences in Resistance Training: A Systematic Review and Meta-Analysis Roberts et al., JSCR, 2020 Exercise Physiology I - Sex-specific aspects in exercise, training and performance 24 Sex Differences in Resistance Training: A Systematic Review and Meta-Analysis Roberts et al., JSCR, 2020 Exercise Physiology I - Sex-specific aspects in exercise, training and performance 25 Sex differences in fatigue resistance? Exercise Physiology I - Sex-specific aspects in exercise, training and performance 26 Sex differences in the development of fatigue Exercise Physiology I - Sex-specific aspects in exercise, training and performance Hunter, Exerc Sport Sci Rev, 2009 27 Sex differences in the development of fatigue Exercise Physiology I - Sex-specific aspects in exercise, training and performance Hunter, Exerc Sport Sci Rev, 2009 28 Sex differences in the development of fatigue Exercise Physiology I - Sex-specific aspects in exercise, training and performance Hunter, Exerc Sport Sci Rev, 2009 29 Sex differences in the development of fatigue? Isometric fatiguing contraction of elbow flexors sustained at 20% MVC young men and women during a stressor (difficult mental task – mathematics) session and control session. à Sex may not always be the only determinant of a m-f-difference! Exercise Physiology I - Sex-specific aspects in exercise, training and performance Hunter, Exerc Sport Sci Rev, 2009 30 Sex differences in muscle fatiguability Summary Female's muscles seem to be more fatigue resistant Differences between males and females differ by task Mechanisms are not yet clear - current hypotheses are: absolute force higher in males à perfusion more limited difference in substrate utilization difference in fiber type activation difference in neuromuscular activation Exercise Physiology I - Sex-specific aspects in exercise, training and performance 31 Sex differences in cardiorespiratory function? Exercise Physiology I - Sex-specific aspects in exercise, training and performance 32 Heart rate, stroke volume and cardiac output at same absolute and same relative intensity (not a specific study, general picture) Differences related to smaller heart and blood volume of women (related to smaller body size). Exercise Physiology I - Sex-specific aspects in exercise, training and performance 33 Maximal ventilation Remember: age-dependent changes male-female differences in V̇O2max à V̇Emax Exercise Physiology I - Sex-specific aspects in exercise, training and performance 34 Maximal oxygen consumption (V̇O2,max) Reasons for differences – women have: smaller muscle mass larger fat mass (values per kg-1) smaller heart à lower cardiac output smaller plasma volume lower hemoglobin level (larger av-difference cannot compensate) Exercise Physiology I - Sex-specific aspects in exercise, training and performance 35 Cardiorespiratory adaptations to training No sex-specific differences in the following adaptations to training: Aerobic, maximal intensity é Q̇max due to é SVmax (é preload, contractility) é muscle blood flow, capillary density é maximal ventilation Aerobic, submaximal intensity Q̇ unchanged é SV, ê HR C. M. Spengl er, Exerci 36 se Physio logy Lab Women Athletes Focus Areas Menstrual Cycle Contraceptives RED-S Pregancy Pelvic floor Empowerment https://www.swissolympic.ch/athleten-trainer/frau-spitzensport/fokusthemen Exercise Physiology I - Sex-specific aspects in exercise, training and performance 37 The Effects of Menstrual Cycle Phase on Exercise Performance in Eumenorrheic Women: A Systematic Review and Meta-Analysis McNulty et al. Sports Medicine, 2020 Exercise Physiology I - Sex-specific aspects in exercise, training and performance 38 The Effects of Menstrual Cycle Phase on Exercise Performance in Eumenorrheic Women: A Systematic Review and Meta-Analysis Performance during the early follicular phase compared with all other menstrual cycle phases. McNulty et al. Sports Medicine, 2020 Exercise Physiology I - Sex-specific aspects in exercise, training and performance 39 The Effects of Menstrual Cycle Phase on Elite Athlete Performance: A Critical and Systematic Review Conclusion: Different sports performance-related parameters are affected during the menstrual cycle among elite athletes, but the parameters themselves and the magnitude and the direction of the effects are inconclusive. Additional longitudinal and prospective studies to systematically monitor on-field performance parameters are urgently required in order to enable recommendations and training individualization in female elite athletes. Maignieé et al. Frontiers in Physiology, 2021 Exercise Physiology I - Sex-specific aspects in exercise, training and performance 40 What do athletes, medical doctors and trainers say? Den Zyklus nützen - Mehr Power dank Planen mit der Mens (SRF Puls 2021) Exercise Physiology I - Sex-specific aspects in exercise, training and performance 41  https://www.swissolympic.ch/athleten-trainer/frau-spitzensport/fokusthemen Exercise Physiology I - Sex-specific aspects in exercise, training and performance 42 Sport and contraceptives https://www.swissolympic.ch/athleten-trainer/frau-spitzensport/fokusthemen https://www.swissolympic.ch/athleten-trainer/frau-spitzensport/fokusthemen?tabId=668687ea-9590-41f5-ba03-523ca3aebb32 Exercise Physiology I - Sex-specific aspects in exercise, training and performance 43 Sport, contraceptives and cycle-adapted training https://www.swissolympic.ch/athleten-trainer/frau-spitzensport/fokusthemen Exercise Physiology I - Sex-specific aspects in exercise, training and performance 44 Sport, contraceptives and cycle-adapted training if you would like to know more, visit the following: https://www.youtube.com/watch?v=Nam2NtPCkIo https://www.swissolympic.ch/athleten-trainer/frau- spitzensport/fokusthemen?tabId=38877d0d-c2cc-484e-8bb3- 5b0b5ab04b12 Exercise Physiology I - Sex-specific aspects in exercise, training and performance 45 Menstrual dysfunction in athletic women Definitions: Eumenorrhea: normal cycle Oligomenorrhea: less frequent mens / irregular cycle Amenorrhea (primary, secondary): absent mens Effects: more often in women in lean-physique sports 5 to 66% of athletes cave: dysfunction ≠ infertility Exercise Physiology I - Sex-specific aspects in exercise, training and performance 46 Menstrual dysfunction in athletic women Potential causes discussed since 1970 History of menstrual dysfunction Acute effects of stress High volume of intense training Low body weight or %fat Hormonal alterations Energy deficit Exercise Physiology I - Sex-specific aspects in exercise, training and performance 47  From Female Athlete Traid to RED-S IOC consensus statement on relative energy deficiency in sports RED-S - 2018 update Energy Deficiency with or without Disordered Eating Mountjoy et al. BrJSportsMed, 2018 Menstrual Disturbances Bone Loss Amenorrhea Osteoporosis http://www.femaleathletetriad.org/ Exercise Physiology I - Sex-specific aspects in exercise, training and performance 48 RED-S (Relative Energy Deficiency in Sports) Potential performance and health consequences https://www.swissolympic.ch/dam/jcr:4b4f2689-8cca-4489-bf36-75e399d0b8f6/SwissOlympic-FS_SS+F_RED-S-de.pdf Exercise Physiology I - Sex-specific aspects in exercise, training and performance 49 RED-S – not only a female issue! According to a 2013-study (cited in NZZamSonntag), the prevalence for eating disturbance across all disciplines is: - up to 45% in female elite athletes NZZ am Sonntag 13. September - up to 19% in male elite athletes 2018 Exercise Physiology I - Sex-specific aspects in exercise, training and performance 50 Position statement on disordered eating in high performance sports British Journal of Sports Medicine, 2020 Exercise Physiology I - Sex-specific aspects in exercise, training and performance 51 Two major eating disorders - in athletes and non-athletes Anorexia nervosa Bulimia nervosa Refusal to maintain minimal normal weight Recurrent binge eating Distorted body image, fear of fatness Lack of control during binges Amenorrhea Purging behaviors (vomiting, laxatives, diuretics) Exercise Physiology I - Sex-specific aspects in exercise, training and performance 52 Osteoporosis – a result of RED-S or eating disorders Osteoporosis decreased bone mineral content (not like osteopenia = age-related loss of bone) deterioration of microarchitecture risk greater in women than men (in general) (especially after menopause, 2-5 x larger) Major contributing factors Estrogen deficiency Inadequate calcium intake Inadequate physical activity Amenorrhea, anorexia nervosa Reduce decline with (weight-bearing / impact) exercise Prevention Ca2+, Vitamin D Perform exercise Maintain eumenorrhea Exercise Physiology I - Sex-specific aspects in exercise, training and performance 53 Exercise in pregnancy Common concerns Acute reduction in uterine blood flow (shunt to active muscle) à fetal hypoxia Fetal hyperthermia from increase in maternal core temperature Maternal CHO usage é, thereby ê CHO availability to fetus Miscarriage Not all is clear, and individual differences apply, also depending on training status. Exercise Physiology I - Sex-specific aspects in exercise, training and performance 54 Pregnancy - Risks and Benefits à in any case: consult with obstetrician to check for other potential risks Exercise Physiology I - Sex-specific aspects in exercise, training and performance 55 Exercise Physiology I - Sex-specific aspects in exercise, training and performance 56 Exercise Physiology I - Sex-specific aspects in exercise, training and performance 57 Pregnancy – exercise recommendations (1) Mild-to-moderate exercise 3 times/week Prefer non-weight-bearing exercise preferable No exercise with risk of falling, loss of balance, etc. No supine exercise after first trimester http://web.uni-plovdiv.bg http://what-when-how.com No scuba diving Exercise Physiology I - Sex-specific aspects in exercise, training and performance 58 Pregnancy – exercise recommendations (2) Stop when fatigued or feeling uncomfortable Ensure adequate caloric intake Dress and hydrate to avoid heat stress Post-partum: Exercise routine should gradually be resumed Benefits >>> Risks, if cautiously undertaken Exercise Physiology I - Sex-specific aspects in exercise, training and performance 59 Pelvic floor (dys)function Exercise Physiology I - Sex-specific aspects in exercise, training and performance 60 Pelvic floor (dys)function - Specific training as a cure Exercise Physiology I - Sex-specific aspects in exercise, training and performance 61 Exercise Physiology I - Sex-specific aspects in exercise, training and performance 62 Notes Exercise Physiology I - Sex-specific aspects in exercise, training and performance 63