There is convincing evidence that the sex differences in muscle mass and strength are sufficient to account for the increased strength and aerobic performance of men compared with women and is in keeping with the differences in world records between the sexes (116). In a second study, 23 transmen administered adult male testosterone doses also produced striking increases in total body muscle size and limb muscle size (by 6.5% to 16.6%) and grip strength (by 18%) compared with age-matched untreated control women (115). In men, the lowest testosterone dose (1.25 g/d) increased mean serum testosterone to 6.9 nmol/L (equivalent to levels seen in early to middle male puberty), resulting in significant increases of total body lean (muscle) mass (2.3%), thigh muscle area (3.0%), and leg press strength (5.5%) compared with the placebo dose that resulted in a serum testosterone of 0.7 nmol/L. The women whose testosterone concentrations were increased to 7.3 nmol/L achieved significant increases in muscle mass and strength (Table 4), ranging from 4.4% for muscle (lean) mass to between 12% and 26% for measures of muscle strength (chest and leg press, loaded stair climb). Corroborative findings are provided by a Norwegian study that examined performance of adolescents in certain athletic events but without reference to contemporaneous circulating testosterone concentrations (107). An important finding from such studies is that androgen-resistant female mice have essentially the same muscle mass and function as wild-type androgen-sensitive females bearing normal AR, whereas androgen-resistant male mice have smaller and weaker muscle mass and function than do wild-type males and comparable instead with wild-type females (101). Hence, individuals with PAIS may have adult male circulating testosterone concentrations but variable androgen sensitivity.
For example, NSAID use has a 90% prevalence in some disciplines.28,62,81,157,200 In 1 study, 32% of American football players used NSAIDs daily, compared with 20% reported for professional soccer players using NSAIDs during the World Cup competitive period.143,192 NSAIDs, used to reduce pain and inflammation, have poorly studied endocrine effects. Human studies have had inconsistent results; some have reported decreased testosterone with prolonged exposure (900 MHz Global System for Mobile Communications radiofrequency from regular cellular phone use or from base stations),45,50 and some have reported increased testosterone in cell phone users.66 This may result from reduced testosterone availability, increased muscle fluid viscosity, and decreased neural stimulation. A longitudinal study by Garolla et al57 showed no changes in testosterone in patients undergoing 2 15-minute sauna sessions per week for 3 months.
Hence, the sex differences in height, where they exist, are largely dependent on postpubertal differences in circulating testosterone when sex differences in height are first expressed. Some factors influencing muscle mass and strength such as physical activity, adiposity, and bone size are also partly androgen-dependent. Numerous factors contribute to the regulation of adult muscle mass, including genetics, race, adiposity, hormones, physical activity (exercise/training), diet, birth order, and bone size (including height) reviewed in (155). One proposal has been that, as men are taller than women, height differences may explain the sex differences in muscle mass and function, which explains some athletic success (116). Hence, such direct investigational studies in otherwise healthy women would risk side effects of virilization that may be only slowly and partly reversible, if at all, as well as potential promotion of hormone-dependent cancers making such studies ethically and practically not feasible. Experimental evidence in mice shows that testosterone increases myoglobin content of muscle with potential for augmenting aerobic exercise performance (96), but this has not been evaluated in humans. There is a clear sex difference in both muscle mass and strength (102–104) even adjusting for sex differences in height and weight (104, 105).
Indeed, muscle cells have multiple nuclei and their number increases with muscle hypertrophy 81, 82. Muscle memory refers to the persistence of cellular phenotype related to previous testosterone exposure . This requirement is not about treatment and treatment choices, which are always private and not relevant to the sports community.
With the exception of one interventional study administering a relatively low testosterone dose (i.e., low for males) to women (112), the available evidence comprises observational studies that can only examine the effects of serum testosterone within physiological female limits or sparse and mostly uncontrolled data from intersex/DSD athletes. Among recreational (nonelite) athletes, an observational study showed a consistent deterioration in athletic performance of transwomen (M2F transgender) athletes corresponding closely to the suppression of circulating testosterone concentrations (175). Converse effects of reduced athletic performance in athletes who undergo suppression of circulating testosterone concentrations from those in the male into the female range have been reported. Given the limited testosterone dose (and concentration) as well as study duration, it is likely that these findings underestimate the magnitude of the impact that sex difference in circulating testosterone has on muscle mass and strength, and therefore on athletic performance. Hence, similar to muscle mass, sex differences in bone size (including length, density, and height) arise after male puberty establishes the marked dichotomy between men and women in adult circulating testosterone concentrations. In one study testosterone treatment of 17 transmen achieving adult male circulating testosterone levels (mean, 31 nmol/L) increased muscle mass by 19.2% (114)., World Rowing and Union Cycliste Internationale (UCI) have all adopted the lower serum testosterone concentration limit of 5 nmol/L for transwomen athletes.|This was related to the subsequent discovery of a single androgen receptor (AR) mediating the effects of AAS in both muscle and reproductive tissue. According to Handelsman, the pharmaceutical industry attempted to dissociate the so-called "androgenic" and "anabolic" effects of AAS in the mid-20th-century in order to create non-masculinizing anabolic agents that would be more suitable for use in women and children. The term anabolic steroid can be dated as far back as at least the mid-1940s, when it was used to describe the at-the-time hypothetical concept of a testosterone-derived steroid with anabolic effects but with minimal or no androgenic effects. The development of muscle-building properties of testosterone was pursued in the 1940s, in the Soviet Union and in Eastern Bloc countries such as East Germany, where steroid programs were used to enhance the performance of Olympic and other amateur weight lifters. Extraction of hormones from urines began in China around 100 BCE.citation needed Medical use of testicle extract began in the late 19th century while its effects on strength were still being studied. Some AAS that are or can be 5α-reduced, including testosterone, DHT, stanozolol, and methyltestosterone, among many others, can or may modulate the GABAA receptor, and this may contribute as an alternative or additional mechanism to their central nervous system effects in terms of mood, anxiety, aggression, and sex drive.|A study conducted in 1993 by the Canadian Centre for Drug-Free Sport found that nearly 83,000 Canadians between the ages of 11 and 18 use steroids. In Canada, researchers have concluded that steroid use among student athletes is extremely widespread. Besides AAS, Handelsman has criticized the term "selective androgen receptor modulator (SARM)" and claims about these agents as well. Although the term "anabolic–androgenic steroid" is technically valid in describing two types of actions of these agents, Handelsman considers the term to be unnecessary and redundant.|Athletes soon recognized that taking epitestosterone along with testosterone could prevent a positive drug test. Fifteen athletes tested positive; additional athletes withdrew from competition and were not tested. Accordingly, use of exogenous testosterone should increase the relative amount of testosterone vs epitestosterone (T/E ratio).|It therefore seems highly unlikely that sex classification would ever be discarded, despite calls on philosophical or sociological grounds to end "gender" classification in sport (10). If sex classification were eliminated, such open or mixed competitions would be dominated almost exclusively by men. Age and weight classifications rely on objective criteria (birth date, weigh-in weight) for eligibility, and so should sex classification. These sex-dichotomous physical features form the basis of, but remain quite distinct from, adult gender roles and identity.|Involve compound movements like squats and deadlifts, which engage multiple muscle groups and demand greater effort, resulting in greater hormonal response. Conversely, prolonged endurance activities, such as long-distance running, often lead to decreased testosterone if recovery isn’t prioritized. Short, high-intensity workouts like sprinting or weightlifting usually cause temporary spikes in testosterone. Peak levels usually occur during late adolescence and begin to decrease in your 30s and beyond. Understanding these aspects can help tailor exercise routines for optimal benefits.|Runners who showed a consistent testosterone baseline recovered from muscle fatigue 48% faster than those whose testosterone dipped post-race. A revealing study from 2023 tracked elite marathoners through a 12-week high-volume training cycle. The most advanced sports programs now use lab-based hormone panels to fine-tune recovery. This synergy is especially effective for athletes in sports with short rest periods between games or matches. Lower cortisol levels allow testosterone to function more effectively. By tracking HRV trends, athletes can stay ahead of hormonal imbalances and adapt training accordingly to preserve optimal testosterone output.|The two dominant bioactive androgens circulating in mature mammals, including humans—testosterone and its more potent metabolite DHT—account for the development and maintenance of all androgen-dependent characteristics, and their circulating levels in men and nonpregnant women arise from steroids synthesized de novo in the testes, ovary, or adrenals (12). Excellent, insightful discussion of the legal and moral complexities of sex and fair competition in elite sports from a legal scholar and former elite female athlete is available (2). The practical need to establish an eligibility criterion for elite female athletic competition led the International Association of Athletic Federations (IAAF) to establish a rule in 2011, endorsed by the International Olympic Committee (IOC) in 2012, for hyperandrogenic women. Scientific studies consistently examine the link between playing sports and testosterone levels. In conclusion, testosterone is a hormone that plays a crucial role in male characteristics and has performance-enhancing effects. Graph comparing the levels of testosterone in male and female athletes.}
When testosterone levels rise too high, the brain sends signals to the pituitary to reduce production. The World Anti-Doping Agency (WADA) maintains the list of performance-enhancing substances used by many major sports bodies and includes all anabolic agents, which includes all AAS and precursors as well as all hormones and related substances. In addition, it was related to misinterpretation of flawed animal androgen bioassays that had been employed to distinguish between androgenic or virilizing effects and anabolic or myotrophic effects (i.e., the Hershberger assay involving the unrepresentative levator ani muscle).
It has also been proposed that the sex difference in athletic performance may be due to genetic effects of an unspecified Y chromosome gene that may dictate taller stature (154), as height is correlated with men’s greater muscle mass. Many if not most other aspects of physiology exhibit sex differences and may therefore enhance the impact of the male advantage in sports performance of the dominant determinants (muscle and hemoglobin). Well-designed, placebo-controlled direct interventional studies of supraphysiological androgen effects on bone in females are few, rarely feasible, and unlikely to be performed for ethical and practical reasons. Additionally, whereas passing through puberty enhances male physical performance, the widening of the female pelvis during puberty, balancing the evolutionary demands of obstetrics and locomotion (136, 137), retards the improvement in female physical performance, possibly driven by ovarian hormones rather than the absence of testosterone (138, 139). There is extensive experimental evidence from genetic mouse models showing that the sex differences in bone size, mass, and function are due to the sex difference in circulating testosterone.

性别: 女性

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