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Despite a decreasing gender gap in exercise participation, there still remains a significant under-representation of women included in sport and exercise medicine research studies.1 A review of 1382 sport and exercise research studies involving over 6 million participants, from 2011 to 2013, found the representation of women to be 39%.1 The complexities of the menstrual cycle are considered major barriers to the inclusion of women in clinical trials. Historically, partially due to concerns of potentially damaging unborn fetuses, medical trials—including drug trials—were conducted solely in men. Further, women were perceived …
Sport, exercise and the menstrual
cycle: where is the research?
G Bruinvels,
R J Burden,
A J McGregor,
K E Ackerman,
M Dooley,
T Richards,
C Pedlar
Despite a decreasing gender gap in exer-
cise participation, there still remains a sig-
nicant under-representation of women
included in sport and exercise medicine
research studies.
A review of 1382 sport
and exercise research studies involving
over 6 million participants, from 2011 to
2013, found the representation of women
to be 39%.
The complexities of the men-
strual cycle are considered major barriers
to the inclusion of women in clinical
Historically, partially due to concerns
of potentially damaging unborn fetuses,
medical trialsincluding drug trials
were conducted solely in men. Further,
women were perceived as more physiolo-
gically variable, therefore utilising only
male participants would allow meaningful
results with fewer participants and less
funding. Since men were viewed as ade-
quate proxies for women, the years of
exclusion of female participants from
research were considered inconsequential.
However, it is now known that women
can respond very differently to drug
treatments than men. Evidence suggests
that women are almost twice more likely
to have an adverse reaction to a drug
than their male counterparts, and 80% of
drugs withdrawn from the market are
due to unacceptable side effects in
When research involving exercise meta-
bolism includes women, participants are
often tested in the early follicular phase of
their menstrual cycle, when hormone
levels are at their lowest, in order to mini-
mise the possible impacts oestradiol and
progesterone may have on the study out-
This type of research practice
leaves much ambiguity around how such
hormones may inuence the unique phy-
siological processes in women, from
blood pressure to substrate metabolism,
thus perpetuating the signicant gap in
understanding how the menstrual cycle
impacts exercise performance. Sheel
recently described a number of sex differ-
ences in the physiological response to
exercise, likely caused in part by ovarian
hormones, highlighting a lack of under-
standing and a need for further research.
We recently reported that 41.7% of
exercising women believe their menstrual
cycle has a negative impact on exercise
training and performance.
largely due to the dearth of sports and
exercise research in women, explanations
for this are lacking. Heavy menstrual
bleeding with unknown or undiagnosed
iron deciency could be a cause but this is
There is a clear need to gain better
understanding of female physiology and
to dene the effects of the cyclical varia-
tions in hormones, both positive and
negative, on athletic performance. Also, a
greater understanding of the menstrual
cycle is needed to address the reported
negative impacts on exercise training
in order to encourage participation and
avoid further disparity in gender
Twitter Follow Georgie Bruinvels at @gbruinvels and
Richard Burden @rich_burden, Charles Pedlar
Contributors GB, RJB, AJM, KEA, MD, TR and CP all
participated in manuscript preparation.
Competing interests None declared.
Provenance and peer review Not commissioned;
externally peer reviewed.
To cite Bruinvels G, Burden RJ, McGregor AJ, et al.
Br J Sports Med Published Online First: [please include
Day Month Year] doi:10.1136/bjsports-2016-096279
Accepted 26 April 2016
Br J Sports Med 2016;0:1.
1 Costello JT, Bieuzen F, Bleakley CM. Where are all the
female participants in Sports and Exercise Medicine
research? Eur J Sport Sci 2014;14:84751.
2 Rademaker M. Do women have more adverse drug
reactions? Am J Clin Dermatol 2001;2:34951.
3 Oosthuyse T, Bosch AN. The effect of the menstrual
cycle on exercise metabolism: implications for exercise
performance in eumenorrhoeic women. Sports Med
4 Sheel AW. Sex differences in the physiology of
exercise: an integrative perspective. Exp Physiol
5 Bruinvels G, Burden R, Brown N, et al. The prevalence
and impact of heavy menstrual bleeding (menorrhagia)
in elite and non-elite athletes. PLoS ONE 2016;11:
University College London, London, UK;
St Marys
University, Twickenham, UK;
ORRECO Ltd, Institute of
Technology, Sligo, Ireland;
English Institute of Sport,
Loughborough, UK;
Brown University, Providence,
Rhode Island, USA;
Massachusetts General Hospital,
Boston, Massachusetts, USA;
The Poundbury Clinic,
Dorchester, Dorset, UK
Correspondence to G Bruinvels, Division of Surgery
and Interventional Science, University College London,
21 University Street, London WC1E 6AU, UK; georgie., @gbruinvels
Bruinvels G, et al.Br J Sports Med Month 2016 Vol 0 No 0 1
BJSM Online First, published on June 6, 2016 as 10.1136/bjsports-2016-096279
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where is the research?
Sport, exercise and the menstrual cycle:
Richards and C Pedlar
G Bruinvels, R J Burden, A J McGregor, K E Ackerman, M Dooley, T
published online June 6, 2016Br J Sports Med
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... Medicina 2023, 59, 1513 2 of 13 often reflective of underlying polycystic ovarian syndrome (PCOS) [5], which affects approximately 10% of reproductive-aged women [6]. Similar cycle disturbances are also present in athletes [7]. Other physiologic variations like the postpartum period [8] and perimenopause [9] have also been followed with menstrual cycle tracking [8,10]. ...
... It may also shed light on variability in the menstrual cycle. The menstrual cycle is not just perceived to influence the female athletes who experience it, but it also has excluded them from being used in scientific studies because it produced "white noise" in the results [7]. There is the possibility that we may improve aspects of physiological and psychological performance by understanding and monitoring athletes' menstrual patterns, yet the quality of the literature regarding physiological effects has been criticized for inappropriate verification of the menstrual cycle phase [25]. ...
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Background and Objectives: The Quantum Menstrual Health Monitoring Study will measure four key reproductive hormones in the urine (follicle-stimulating hormone, FSH; estrone-3-glucuronide, E13G; luteinizing hormone, LH; and pregnanediol glucuronide, PDG) to characterize patterns that predict and confirm ovulation, referenced to serum hormones and the gold standard of the ultrasound day of ovulation in participants with regular cycles. These normal cycles will provide a reference for comparison to irregular cycles in subjects with polycystic ovarian syndrome (PCOS) and athletes. Materials and Methods: Participants will track their menstrual cycles for 3 months and be provided with an at-home urine hormone monitor (Mira monitor) to predict ovulation. The day of ovulation will be confirmed with serial ultrasounds completed in a community clinic. Urine results will be compared to serum hormone values. Other markers of menstrual health, such as bleeding patterns and temperature changes, will be determined using a customized app. Three groups will be recruited. Group 1 will include those with consistent regular cycle lengths (between 24–38 days), and will be compared to two groups with irregular cycle lengths (with increased cycle length variability and longer cycles). Group 2 will include those with polycystic ovarian syndrome (PCOS) with irregular cycles and Group 3 will include individuals participating in high levels of exercise with irregular cycles. Hypothesis: The Mira monitor quantitative urine hormone pattern will accurately correlate with serum hormonal levels and will predict (with LH) and confirm (with PDG) the ultrasound day of ovulation in those with regular cycles as well as those with irregular cycles. Rationale: Once the ultrasound validation is complete, tools like the Mira monitor with a customized app may become a new standard for at-home and remote clinical monitoring of the menstrual cycle without having to use labor-intensive follicular-tracking ultrasound or follow serum hormone changes. Conclusions: Precision monitoring of the menstrual cycle is expected to impact individuals who want to increase their menstrual health literacy and guide decisions about fertility.
... One truly neglected area of research is that into the relationship between the menstrual cycle and performance (Bruinvels et al., 2017). Summarizing what is known, two recent reviews from 2021 concluded that the currently limited evidence suggests a variable association between the menstrual cycle and several performance measures, such as endurance, power resistance, ligament stiffness, decisionmaking skills, psychology, and competitiveness (Carmichael et al., 2021;Meignié et al., 2021). ...
Rational: To discuss the use of hormonal contraception (HC) in elite women's competitive sports from an anti-doping perspective because 1) it changes the natural female hormonal milieu; 2) is used to manipulate the menstrual cycle with performance enhancement intent; 3) even though lowering endogenous testosterone levels, some HCs contain testosterone-like androgenic compounds with potential performance-enhancing effects. Results: A complex interaction between rapidly advancing sports-relevant biomedical scientific discoveries, societal changes concerning sex and gender, and a zero-tolerance anti-doping ideology, leads to contentious results, jeopardizing the premises defining and protecting contemporary elite sport in general and that of women in particular. Discussion and conclusions: This is in part because of the two out of three criteria for inclusion on the World Anti-Doping Agency's List of forbidden substances and methods: i) actual or potential for performance enhancement, ii) actual or potential for health risk, and iii) counter to the Spirit of Sport concept. These criteria would suffice for the inclusion of HC on the List, especially in their androgenic form. The fact that they are not is good for women's reproductive rights but also illustrates the arbitrariness of the administration of WADA's Prohibited List of substances and methods in elite sports.
... The effects of estrogen on performance have been studied predominantly in female athletes. How, or if, estrogen affects performance is not entirely understood due to changes in hormonal concentrations through the menstrual cycle, alterations of estrogen and progesterone resulting from oral contraceptive use, and changes in hormonal concentrations occurring around menopause (37,(99)(100)(101). Despite these limitations, several investigations have examined how performance may be influenced at different phases of the menstrual cycle (102,103). ...
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There are well known sex differences in parameters of physical fitness/performance due to changes occurring during sexual development. Thus, many sport and athletic events have regulations separating male and female participants. However, the inclusion or exclusion of transgender individuals in athletics has recently received outsized attention despite relatively few cases of transgender athletes. When determining which athletic gender category trans individuals should be permitted to compete in, it is important to understand the level of physical fitness/performance these individuals possess relative to their cisgender counterparts. Unfortunately, there are few studies investigating this topic, and several complications that confound this research. The current review seeks to discuss sex and gender as concepts, review sex differences in fitness/performance and how they develop, and then, consider how current evidence suggests that trans individuals compare to cis individuals. Finally, this review seeks to offer considerations for whether trans individuals should be excluded from sports and athletics, and how future research should proceed to better understand this marginalized population.
... To minimize the effect of the menstrual cycle on the study outcomes, female athletes were tested during their early follicular phase 30 . The menstrual cycle phase was accurately identified with the help of a period tracker application 31 using the self-reported onset of menses method. ...
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The purpose of this study was to assess the effects of acute caffeine supplementation on physical performance and perceived exertion during taekwondo-specific tasks in male and female athletes with varying expertise. In a double-blinded, randomized, placebo-controlled crossover study design, 52 young athletes from elite (n = 32; 16 males and 16 females) and sub-elite competitive level (n = 20; 10 males and 10 females) participated. Athletes performed taekwondo-specific tasks including the taekwondo-specific agility test (TSAT), 10 s frequency speed of kick test (FSKT-10 s) and multi-bout FSKT (FSKT-multi) under the following conditions: (1) Caffeine (CAF; 3 mg kg −1), placebo (PLA), and no supplement control (CON). Session rating of perceived exertion (s-RPE) was determined after the tests. Findings show that regardless of condition, males performed better than females (p < 0.05) and elite athletes had superior performance compared to their sub-elite counterparts (p < 0.05). For the TSAT (p < 0.001), FSKT-10s (p < 0.001), and FSKT-multi (p < 0.001), CAF enhanced performance in elite female athletes compared to sub-elite females. Likewise, CAF ingestion resulted in superior performance in elite males compared to sub-elite males for FSKT-10s (p = 0.003) and FSKT-multi (p < 0.01). The ergogenic potential of CAF during taekwondo-specific tasks appears to be related to a competitive level, with greater benefits in elite than sub-elite athletes.
... Eirale et al. [35] and Hägglund et al. [36] have shown that player availability for matches affects team success in elite-level men's club football, so it is likely that team success in elite-level women's club football is similarly affected by player availability. Despite limited evidence to support their view [37,38], half of the study participants, including the majority of players, believed the hormonal changes associated with the menstrual cycle were a risk factor for injury. There is some preliminary evidence suggesting that the incidence rate and type of injuries may vary across the eumenorrheic menstrual cycle [37], and that symptoms associated with the menstrual cycle affect athletes' training and competition availability [39], but robust studies confirming the relationship between menstrual cycle phase and injury occurrence do not currently exist. ...
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Background To manage injuries effectively, players, head coaches, and medical personnel need to have excellent knowledge, attitudes, and behaviours in relation to the identification of risk factors for injuries, the implementation of injury prevention initiatives, as well as the implementation of effective injury management strategies. Understanding the injury context, whereby specific personal, environmental, and societal factors can influence the implementation of injury prevention initiatives and injury management strategies is critical to player welfare. To date, no qualitative research investigating the context of injuries, has been undertaken in elite-level women’s football. The aim of our study was to explore the knowledge, attitudes, and behaviours of players, head coaches, and medical personnel in the Irish Women’s National League (WNL) to injury prevention and injury management. Methods We used qualitative research methods to explore the knowledge, attitudes, and behaviours of players, head coaches, and medical personnel in the Irish WNL to injury prevention and injury management. Semi-structured interviews were undertaken with 17 players, 8 medical personnel, and 7 head coaches in the Irish WNL. The data were analysed using thematic analysis. Our study is located within an interpretivist, constructivist research paradigm. Results The participants had incomplete knowledge of common injuries in elite-level football, and many held beliefs about risk factors for injuries, such as menstrual cycle stage, which lacked evidence to support them. Jumping and landing exercises were commonly used to reduce the risk of injuries but evidence-based injury prevention exercises and programmes such as the Nordic hamstring curl, Copenhagen adduction exercise, and the FIFA 11+ were rarely mentioned. Overall, there was dissatisfaction amongst players with their medical care and strength and conditioning (S & C) support, with resultant inadequate communication between players, head coaches, and medical personnel. Conclusion Poor quality and availability of medical care and S & C support were considered to be a major obstacle in the effective implementation of injury risk reduction strategies and successful return-to-sport practices. More original research is required in elite-level women’s football to explore injury risk factors, injury prevention initiatives, and contextual return-to-sport strategies, so that players, head coaches, and medical personnel can use evidence that is both up-to-date and specific to their environment.
The underrepresentation of female research participants, women, and girls has been highlighted as an issue of concern within a variety of research areas and disciplines across academia. More specifically, this lack of visibility has contributed to widening knowledge gaps regarding these populations while also perpetuating and strengthening existing inequities. Given these concerns, the purpose of this review was to explore whether similar imbalances could exist within the sport psychology literature and, if so, what future research projects might be completed to rectify these issues. To do so, all articles ( n = 3,005) published between the years of 2011 and 2021 in five journals of sport psychology were assessed. Following an analysis of the relevant studies collected, it was found that more articles including all boys, men, and male athletes ( n = 343) were published within this time frame compared with articles including exclusively girls, women, and female athletes ( n = 155). Additionally, it also appeared that research working with girls, women, and female athletes was lacking: (a) in recreational sport, (b) at both young and older ages, and (c) within team sport contexts. Further, most of the studies assessed often conflated participant sex- and gender-descriptive terminology. As such, it is highly encouraged that researchers in sport psychology make greater strides to conduct purposeful and targeted research focusing on girls, women, and female athlete participants and their specific issues over the coming years.
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Sex differences in physiological responses to various stressors, including exercise, have been well documented. However, the specific impact of these differences on exposure to hypoxia, both at rest and during exercise, has remained underexplored. Many studies on the physiological responses to hypoxia have either excluded women or included only a limited number without analyzing sex-related differences. To address this gap, this comprehensive review conducted an extensive literature search to examine changes in physiological functions related to oxygen transport and consumption in hypoxic conditions. The review encompasses various aspects, including ventilatory responses, cardiovascular adjustments, hematological alterations, muscle metabolism shifts, and autonomic function modifications. Furthermore, it delves into the influence of sex hormones, which evolve throughout life, encompassing considerations related to the menstrual cycle and menopause. Among these physiological functions, the ventilatory response to exercise emerges as one of the most sex-sensitive factors that may modify reactions to hypoxia. While no significant sex-based differences were observed in cardiac hemodynamic changes during hypoxia, there is evidence of greater vascular reactivity in women, particularly at rest or when combined with exercise. Consequently, a diffusive mechanism appears to be implicated in sex-related variations in responses to hypoxia. Despite well-established sex disparities in hematological parameters, both acute and chronic hematological responses to hypoxia do not seem to differ significantly between sexes. However, it is important to note that these responses are sensitive to fluctuations in sex hormones, and further investigation is needed to elucidate the impact of the menstrual cycle and menopause on physiological responses to hypoxia.
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With the increase of female sports participants, the attention to female sports protection is getting higher and higher. However, most past sports science and sports medicine research has emphasized men, so the possible different effects of gender factors are less discussed. To explore whether women are more prone to sports injuries, we should start with the differences between men and women, which include biological sex (sex) and social sex (gender). This article reviewed epidemiological data on the incidence of sports injuries in male and female athletes and found that overall, there was no difference in the incidence of sports injuries between male and female athletes. However, when looking at specific sports, such as swimming, and water polo, there were sex differences in the incidence of sports injuries. For common sports injuries, such as anterior cruciate ligament injuries, stress fractures, and concussions, female athletes had a higher incidence of injury. The current challenges in sports injury prevention work or related research include the lack of research in women's sports science and sports medicine and the disregard of social gender factors. Finally, a classification of sports injury risk factors based on the risk modification and sports injury prevention models incorporating sex and gender considerations are recommended for future practice.
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Objectives: The aim of the study was to assess the influence of menstrual cycle phase on injury incidence, severity and type in elite female professional footballers over three seasons. Methods: Time-loss injuries and menstrual cycle data were prospectively recorded for 26 elite female football players across three seasons. The menstrual cycle was categorised into four phases using a standardised model: menstruation (phase 1; P1), remainder of follicular phase (phase 2; P2), early luteal (phase 3; P3), and pre-menstrual phase (phase 4; P4). Injury incidence rates (IRR) and ratios (IIRR) were calculated for overall injuries, injury type, contact vs non-contact, game/training and severity of injury. Results: 593 cycles across 13,390 days were tracked during the study and 74 injuries from 26 players were eligible for analysis. Muscle injuries were the most prevalent sub-type (n=41). When comparing IRR between phases (reference: P1), injury rates were highest in P4 for overall (IIRR: 2.30 [95% CI: 0.99-5.34; p=0.05]), muscle-specific (6.07 [1.34-27.43; p=0.02]), non-contact (3.05 [1.10-8.50; p=0.03]) and ≤7 days time-loss injuries (4.40 [0.93-20.76; p=0.06]). Muscle-specific (IIRR P3:P1: 5.07 [1.16-22.07; p=0.03]) and ≤7 days time-loss (4.47 [1.01-19.68; p=0.05]) injury risk were also significantly higher in P3. No anterior cruciate ligament injuries were recorded across the monitoring period. Conclusion: Injury risk was significantly elevated during the luteal phase of the menstrual cycle ( P3 and P4) among elite female professional footballers. Further research is urgently needed to better understand the influence of the menstrual cycle on injury risk and to develop interventions to mitigate risk.
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The female hormones, oestrogen and progesterone, fluctuate predictably across the menstrual cycle in naturally cycling eumenorrhoeic women. Other than reproductive function, these hormones influence many other physiological systems, and their action during exercise may have implications for exercise performance. Although a number of studies have found exercise performance and in particular, endurance performance to vary between menstrual phases, there is an equal number of such studies reporting no differences. However, a comparison of the increase in the oestrogen concentration (E) relative to progesterone concentration (P) as the E/P ratio (pmol/nmol) in the luteal phase in these studies reveals that endurance performance may only be improved in the mid-luteal phase compared with the early follicular phase when the E/P ratio is high in the mid-luteal phase. Furthermore, the late follicular phase, characterized by the pre-ovulatory surge in oestrogen and suppressed progesterone concentrations, tends to promote improved performance in a cycling time trial and future studies should include this menstrual phase. Menstrual phase variations in endurance performance may largely be a consequence of changes to exercise metabolism stimulated by the fluctuations in ovarian hormone concentrations. The literature suggests that oestrogen may promote endurance performance by altering carbohydrate, fat and protein metabolism, with progesterone often appearing to act antagonistically. Details of the ovarian hormone influences on the metabolism of these macronutrients are no longer only limited to evidence from animal research and indirect calorimetry but have been verified by substrate kinetics determined with stable tracer methodology in eumenorrhoeic women. This review thoroughly examines the metabolic perturbations induced by the ovarian hormones and, by detailed comparison, proposes reasons for many of the inconsistent reports in menstrual phase comparative research. Often the magnitude of increase in the ovarian hormones between menstrual phases and the E/P ratio appear to be important factors determining an effect on metabolism. However, energy demand and nutritional status may be confounding variables, particularly in carbohydrate metabolism. The review specifically considers how changes in metabolic responses due to the ovarian hormones may influence exercise performance. For example, oestrogen promotes glucose availability and uptake into type I muscle fibres providing the fuel of choice during short duration exercise; an action that can be inhibited by progesterone. A high oestrogen concentration in the luteal phase augments muscle glycogen storage capacity compared with the low oestrogen environment of the early follicular phase. However, following a carbo-loading diet will super-compensate muscle glycogen stores in the early follicular phase to values attained in the luteal phase. Oestrogen concentrations of the luteal phase reduce reliance on muscle glycogen during exercise and although not as yet supported by human tracer studies, oestrogen increases free fatty acid availability and oxidative capacity in exercise, favouring endurance performance. Evidence of oestrogen's stimulation of 5'-AMP-activated protein kinase may explain many of the metabolic actions of oestrogen. However, both oestrogen and progesterone suppress gluconeogenic output during exercise and this may compromise performance in the latter stages of ultra-long events if energy replacement supplements are inadequate. Moreover, supplementing energy intake during exercise ith protein may be more relevant when progesterone concentration is elevated compared with menstrual phases favouring a higher relative oestrogen concentration, as progesterone promotes protein catabolism while oestrogen suppresses protein catabolism. Furthermore, prospective research ideas for furthering the understanding of the impact of the menstrual cycle on metabolism and exercise performance are highlighted.
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To identify the prevalence and impact of heavy menstrual bleeding (HMB) in exercising females where anemia may have a significant effect on training and performance a 'Female Health Questionnaire' was designed incorporating a validated diagnostic HMB series, demographics, exercise ability data, training status, anemia, iron supplementation and whether the menstrual cycle had affected training and performance. The survey was conducted in two stages; initially online, advertised via social media, and then repeated via face-to-face interviews with runners registered for the 2015 London Marathon. 789 participants responded to the online survey, and 1073 completed the survey at the marathon. HMB was reported by half of those online (54%), and by more than a third of the marathon runners (36%). Surprisingly, HMB was also prevalent amongst elite athletes (37%). Overall, 32% of exercising females reported a history of anemia, and 50% had previously supplemented with iron. Only a minority (22%) had sought medical advice. HMB is highly prevalent in exercising females, associated with self-reported anemia, increased use of iron supplementation and a perceived negative impact on performance. Further research is needed to investigate the impact of HMB, iron deficiency and anemia in exercising females.
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Abstract The aim of this study is to estimate the ratio of male and female participants in Sports and Exercise Medicine research. Original research articles published in three major Sports and Exercise Medicine journals (Medicine and Science in Sports and Exercise, British Journal of Sports Medicine and American Journal of Sports Medicine) over a three-year period were examined. Each article was screened to determine the following: total number of participants, the number of female participants and the number of male participants. The percentage of females and males per article in each of the journals was also calculated. Cross tabulations and Chi-square analysis were used to compare the gender representation of participants within each of the journals. Data were extracted from 1382 articles involving a total of 6,076,580 participants. A total of 2,366,968 (39%) participants were female and 3,709,612 (61%) were male. The average percentage of female participants per article across the journals ranged from 35% to 37%. Females were significantly under-represented across all of the journals (χ(2) = 23,566, df = 2, p < 0.00001). In conclusion, Sports and Exercise Medicine practitioners should be cognisant of sexual dimorphism and gender disparity in the current literature.
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Up to 5% of all hospital admissions are the result of adverse drug reactions (ADRs). Identifying those factors which may predispose to ADRs is essential for risk management. Amongst the known risk factors for adverse reactions are increasing age, polypharmacy, liver and renal disease as well as being female. Female patients have a 1.5- to 1.7-fold greater risk of developing an ADR, including adverse skin reactions, compared with male patients. The reasons for this increased risk are not entirely clear but include gender-related differences in pharmacokinetic, immunological and hormonal factors as well as differences in the use of medications by women compared with men. Women generally have a lower lean body mass, a reduced hepatic clearance, have differences in activity of cytochrome P450 (CYP) enzymes (40% increase in CYP3A4, varied decrease in CYP2D6, CYP2C19 and CYP1A2), and metabolize drugs at different rates compared with men. Other important factors include conjugation, absorption, protein binding and renal elimination, which may all have some gender-based differences. However, how these differences result in an increased risk of ADRs is not clear. There are pharmacodynamic differences between men and women, seen particularly with cardiac and psychotropic medications. There is no doubt that chlorpromazine, fluspirilene and various antipsychotics appear more effective in women than men for the same dosage and plasma concentration. Similarly, women are at increased risk of QT prolongation with certain anti-arrhythmic drugs compared with men even at equivalent serum concentrations. The mechanisms are unknown. Increasingly the evidence is that idiosyncratic drug reactions, particularly cutaneous reactions, appear to have an immunological etiology. It is possible that gender difference in T cell activation and proliferation account for this as well as the increased prevalence of skin diseases such as systemic lupus erythematosus and photosensitivity. Whatever the mechanism(s), it is important to be aware that gender is a significant factor in ADRs.
Video slideshow introduction to the Symposium by Symposium Speaker A. William Sheel can be found here.