- 1Faculty of Medicine, University of Bern, Bern, Switzerland
- 2School of Health and Caring Sciences, University of West Attica, Athens, Greece
- 3Ultra Sports Science Foundation, Pierre-Benite, France
- 4Centre for Rehabilitation & Sports Medicine, Bern University Hospital, University of Bern, Bern, Switzerland
- 5Department of Sports, Higher Institute of Educational Sciences of the Douro, Penafiel, Portugal
- 6CI-ISCE, ISCE (Instituto Superior de Ciências Educativas) Douro, Penafiel, Portugal
- 7Department of Sports, Instituto Politécnico de Bragança, Bragança, Portugal
- 8Research Center for Active Living and Wellbeing (LiveWell), Instituto Politécnico de Bragança, Bragança, Portugal
- 9Federal University of São Paulo, São Paulo, Brazil
- 10Institute of Primary Care, University of Zurich, Zurich, Switzerland
- 11Liberal Arts Department, American University of the Middle East, Egaila, Kuwait
- 12Faculty of Sport and Physical Education, University of Belgrade, Belgrade, Serbia
- 13Medbase St. Gallen am Vadianplatz, St. Gallen, Switzerland
Introduction: Triathlon events have gained popularity in recent years. With the increasing participation of women, aspects that influence performance and physiology, as well as differences between women and men, are of interest to athletes and coaches. A review of the existing literature concerning differences between women and men in triathlon is lacking. Therefore, this narrative review aimed to compare female and male triathletes in terms of participation, performance, and the different influences on performance (e.g., physiology, age, pacing, motivation).
Methods: A literature search was conducted in PubMed and Scopus using the search terms “female triathletes”, “women in triathlon”, “triathlon AND gender difference”, and “triathlon AND sex difference”. 662 articles were found using this search strategy, of which 147 were relevant for this review. All distances from sprint to ultra-triathlon (e.g., x-times IRONMAN® distance) were analyzed.
Results: The results showed that the participation of female triathletes, especially female master triathletes increased over time. An improvement in the performance of female and older triathletes was observed at the different distances in the last decades. Sex differences in performance varied across distances and in the three disciplines. Female triathletes showed a significantly lower VO2max and higher lactate thresholds compared to men. They also had a higher body fat percentage and lower body mass. The age for peak performance in the IRONMAN® triathlons is achieved between 25 and 39 years for both women and men. Strong predictors of IRONMAN® race performance in both female and male triathletes include achieving a personal best time in a marathon and a previous best time in triathlon races.
Conclusion: Further studies need to balance the representation of female and male athletes in study cohorts to ensure that findings are relevant to both sexes. Another research gap that should be addressed by future studies is the effect of menstruation and female hormones, the presence of premenstrual syndrome, and the impact of pregnancy and childbirth on the triathlon performance to better understand the differences with men and to account for hormonal fluctuations in training.
1 Introduction
Triathlon is a unique endurance sports discipline in which swimming, cycling and running are combined and performed one after the other (1). The length of the individual disciplines varies depending on the length of the event. The different distances are shown in Table 1 (2, 3). Distances longer than the IRONMAN® distance are typically referred to as ultra-triathlons (3). Each of these distances places specific demands on the athletes’ physical performance, physiological systems, training preparation and recovery strategies.
In recent years, endurance events such as marathons and triathlons have become increasingly popular (4–7). In triathlon events, the IRONMAN® triathlon is especially popular, as both the number of races and athletes increase annually (8). Due to the increasing interest in participation in triathlon, numerous studies have been published in recent years addressing various aspects of such races, including participation trends (3, 9–11), performance trends over the years (12–14), predictive variables of performance (15–18), the different characteristics of participants (19–22), age-related aspects (23–27), training (28–30), nutrition (31, 32) and pacing (33–36).
With increasing participation, the performance also changed. In the Ironman World Championship “IRONMAN® Hawaii”, both elite (24) and age group athletes (37) have improved their performance over the last decades. In contrast, Sousa et al. showed a negative trend in the performance of women and men in ultra-triathlon (Double Iron, Triple Iron, Quintuple Iron (19 km swimming, 900 km cycling, and 211 km running) and Deca Iron ultra-triathlon between 1985 and 2018 (38). Several studies have aimed to identify the factors influencing endurance performance in running and triathlon. Success in endurance events is determined by a complex interplay among various factors, including oxidative capacity, the energy cost of locomotion, substrate efficiency, fatigue resistance and musculoskeletal conditioning, race nutrition, gastrointestinal function, age, sex, experience, pain management, decision-making, and motivation and psychological disposition (14, 34, 39–44).
While triathlon was originally heavily dominated by men, the number of female participants has increased significantly in recent decades. Women have made significant progress in both amateur and professional sports and have increasingly established themselves in competitions (45–47). Nevertheless, there are still striking differences in participation rates, performance, and physiological requirements between female and male athletes.
Since the number of female triathletes has increased and sex influences on performance, significant attention has been paid to the sex difference in endurance sports performance, notwithstanding the fact that the number of scientific studies involving the female population remains significantly lower than those involving the male population (48). Triathlon provides an intriguing alternative model to analyze the sex difference in endurance performance because the sex difference can be analyzed both for the same subject as a whole and for the three disciplines separately (3, 13, 25, 49). With the increase in women's participation in amateur and elite endurance sports over the past three decades, the sex performance gap appears to be narrowing (7, 10). This also appears to be associated with improvements in women's performance in recent decades (45–47). Some authors have wondered whether the sex gap in endurance performance will close (50–52). However, more recent studies have shown that the sex gap is no longer narrowing (53, 54).
The gap between sexes in endurance performance is a crucial subject for athletes, coaches and researchers in sports science and sports medicine. A comprehensive understanding of these differences is important for identifying the challenges and opportunities specific to women in triathlon and for developing strategies to promote sex equality and participation in sports. According to a recent consensus of the American College of Sports Medicine, women had a 10%–30% lower performance in sports, where endurance and muscle power played a dominant role (55). The aim of the present narrative review is therefore to provide insights into the differences between female and male triathletes in terms of participation, performance and the various influences on performance (e.g., physiology, age, pacing, motivation). The main focus is on the extent to which the performance of women and men differs at different triathlon lengths and which physiological and psychological factors influence these differences. In addition to the obvious differences in performance, the numerous social, cultural and biological factors that can play a role are also taken into account.
2 Methods
To comprehensively examine the participation and performance trends of women in triathlon as well as the differences between women and men, a narrative review was conducted to identify, select and analyze relevant literature. For this narrative review, a literature search was performed using PubMed and Scopus databases. The search was not limited by publication date; all studies published until November 2024 were considered.
The following terms were used for the literature search: “female triathlete”, “women in triathlon”, “triathlon AND gender difference”, “triathlon AND sex difference”. All studies on women's participation, performance and influencing factors in triathlon (e.g., physiology, age, training, motivation, pacing, experience) were included. Studies that did not specifically address these topics or focused exclusively on male athletes were excluded.
Figure 1 shows the flowchart of the searching strategy used.
Following the literature search, the identified studies were categorized based on their research focus according to the main topics of interest of the present narrative review. The findings of the literature search were systematically recorded in tables. These tables contain the key information for each article, including the number of participants, the triathlon distance, the observation of the study and the main findings. This ensured that the overview of the relevant literature was clearly structured. Several studies were included twice or more in each related category of interest because they focused on two or more of the areas of interest.
3 Results and discussion
The focus of the present narrative review was on participation (11 studies) and performance trends (66 studies) of women at different triathlon distances and the factors influencing performance, such as aspects of physiology and anthropometry (47 studies), age (20 studies), training/experience (23 studies), pacing (11 studies), nutrition (4 studies) and motivation (8 studies).
3.1 Participation
A total of 11 studies focused on the participation trends of female triathletes were identified. Participation in the IRONMAN® 70.3 (6), the IRONMAN® (7) and the ultra-triathlon (e.g., Double and Triple Iron) (9, 56) has steadily increased for both sexes, while numbers in Quadruple to Deca Iron events remain stable (3, 57). No major changes in participation were also observed in the Olympic distance triathlon (58). This is also supported by the analysis of the Olympic distance “Zurich Triathlon” between 2000 and 2010, where only the participation of female triathletes aged 40–54 years increased (47). However, no studies could be found with current numbers of participants at the Olympic distance.
Figure 2 illustrates participation trends in female and male triathletes across different time periods and race distances, as reported by various studies. The figure highlights differences in participation rates, showing that despite an increase in female participation over time, the number of male triathletes remains consistently higher.

Figure 2. The participation rate trends across different studies (3, 9, 11, 37, 47, 57, 58, 60, 225, 226).
Table 2 shows the main findings of studies investigating the changes in participation in different triathlon distances over time.

Table 2. Overview of the key findings of studies investigating the participation trends in different triathlon distances.
3.1.1 Female participation
The number of female participants has progressively increased since 1980 (37). In the 1981 “IRONMAN® Hawaii” event, there were 20 female finishers (6% of participants), while in 2010 the number rose to 470 (27% of participants) (7, 37). A look at the IRONMAN® Triathlon World Championship between 1983 and 2012 shows that the number of female participants increased more rapidly than the overall number of participants. The number of male participants rose from 720 to 1362 during this period, which corresponds to a relative increase of 189%, while the number of women increased by 455% (from 115 to 524 participants) (59). This trend can also be observed in the marathon running. In a study between 1980 and 2009, Lepers et al. showed that the participation of female marathon runners increased at a higher rate (5). In contrast, a study investigating sex differences in IRONMAN® races worldwide between 2002 and 2022 found that the number of male finishers increased more than the number of female finishers, leading to an increase in the men-to-women ratio over the years (60).
The reasons for the increase in female participation are not clear. Still, social phenomena such as an enhanced focus on personal physical fitness and the positive impact of a healthy lifestyle on longevity could have been potential explanations (61). The increasing social acceptance of “active” women may also have played a role in the increased participation of women (62). Furthermore, greater media visibility of female athletes, targeted initiatives to promote women in endurance sports, and a broader societal shift toward sex equality in sport may have contributed to this trend. Role models in elite sports and the growing availability of women-only races or training groups could also be motivating factors.
In the context of age group triathletes, the rise in the number of female participants has surpassed that of male participants (7). Increased life expectancy and improved training opportunities for master athletes could explain the growing participation in endurance events in recent years (37).
Despite the increase in female participants, the proportion of women in triathlon events remains lower compared to men, with the female rate varying between 25% and 40% of the total field (13, 37, 58). In contemporary times, female triathletes have access to comparable training and competitive opportunities as their male counterparts across most regions globally. Nonetheless, female participation rates persistently lag below those of men, particularly in long-distance triathlon events (63). The female participation rate seems to have declined in the IRONMAN® to Double Deca Iron ultra-triathlon between 1978 and 2013. Rüst et al. found the highest percentage of women at the “IRONMAN® Hawaii” with 22.1% and the lowest at the Deca Iron ultra-triathlon with 6.5% (64). The analysis of the Triple Iron ultra-triathlon between 1988 and 2011 indicated that the number of female participants remained constant at 8%, while overall participation, especially among men, increased over this period (11). Other studies have also found a low participation rate of female triathletes in ultra-triathlons (3, 65). Additionally, due to the different men-to-women ratios in the different race lengths, the ratio also varied across the age groups. A study investigating sex differences in IRONMAN® age group triathletes found that the ratio increased with increasing age (60).
In contrast to other traditional endurance events such as marathons, the participation rate of female athletes in triathlons, particularly at the IRONMAN® distance, persists at a lower level (7). However, the rate is higher than for ultra-endurance events like a 161-km ultra-marathon (7). Knechtle et al. have recently shown that female runners participate more often in shorter race distances and less often in marathons and ultra-marathons, and that the male-to-female ratio increases with increasing race distance (66). The lower rate of women finishers in longer race distances is also consistent with the findings in duathlon (67). This might be explained by motivational reasons, differences in training practices and sociocultural contexts (7, 68, 69).
Data from Hunter and Stevens provided evidence that lower female participation in competitions such as marathon running and less depth among women competitors could exacerbate the sex difference in running speed beyond the sole physiological sex difference (70).
Future research on triathlon participation should place greater focus on current trends among female athletes, as recent data in this area remain limited. In addition, studies should consider the factors influencing female athletes’ engagement in the sport. Understanding the barriers to participation, such as the availability of resources, training support, and the possible impact of social and economic limitations based on sex, should receive careful consideration. Further investigation into the specific motivations driving female participation, and how these may differ from or align with those of male athletes would also provide valuable insights.
3.2 Performance
3.2.1 Changes in performance across years
In addition to the increase in participation in recent decades, there has also been an increase in performance. Both elite and non-elite female and male triathletes have demonstrated performance improvements and sex differences in performance have received considerable attention over the last few decades (7, 37, 63, 64, 71).
Table 3 lists the key findings of studies that have examined changes in performance at different triathlon distances across years. In terms of overall race time, women have shown greater improvements compared to men. For example, during the period between 1995 and 2011 at the “IRONMAN® Switzerland”, the top 10 elite women demonstrated a more pronounced improvement in total time by 12.7%, whereas the top 10 elite men improved their total time by 6.4% (72). It should be noted that women accounted for 10.6% of all finishers in this study.

Table 3. Overview of key findings from studies investigating performance trends in different triathlon distances across the years.
3.2.2 Sex difference in overall performance
Sex differences in performance vary across the different disciplines and distances in triathlon. (7) Table 4 shows the key findings of the studies investigating the sex difference in overall performance in different distances from Olympic distance to Double Deca ultra-triathlon. With the increase in female participation in recent years, the gap between sexes in performance seems to be generally narrowing (7, 10). Although there has been an improvement in female performance (73), there still exists a gap between the sexes (74).

Table 4. Overview of key findings from studies investigating sex differences in overall performance in different triathlon distances.
The sex gap in overall triathlon performance at the IRONMAN® distance in elite triathletes has been reduced to less than 10% thanks to significant improvements in marathon performance among women (63). Compared to the IRONMAN® distance, a recent study demonstrated that in the Olympic distance, an 8% sex difference in overall performance was observed among amateur athletes (71). Higher differences were evident when examining the top 10 amateur athletes at the World Championship from 2009 to 2011 (12% sex difference in overall race time) (75) and in an analysis of the “Zurich Triathlon” between 2000 and 2010 for the top 5 overall elite triathletes (14.8% in overall race time) (47). It should be noted that the comparison of sex-specific differences is complicated by the varying competition conditions at different events (63) and the diverse levels of performance (71).
When comparing the sex differences in the IRONMAN® performance with those in the Double or Triple Iron ultra-triathlon distances, discrepancies amplify with the length of the ultra-triathlon (3). While the sex difference remained consistent on the Double Iron ultra-triathlon distance over the years (56), there was an observable augmentation in the performance gap between sexes on the Triple Iron ultra-triathlon distance (11). Women became slower in the Triple Iron ultra-triathlon between 1988 and 2011, increasing in the sex difference from 10% in 1992 to 42% in 2011 (11).
Despite some authors questioning whether the gap between women and men can be closed (50–52), newer studies have not confirmed this and have shown that the sex difference in both endurance performances (53, 54) and anaerobic sprints (76) is no longer decreasing. It appears that the sex difference in performance has reached a plateau (53). This is also evidenced by an analysis of the “IRONMAN® Hawaii” between 1981 and 2007 (13).
3.2.3 Sex differences in performance in the different split disciplines
Performance disparities between sexes are evident in the subdisciplines of triathlon (swimming, cycling, running) (63). For instance, at the IRONMAN® 70.3 and IRONMAN® distance, a smaller sex difference was observed in swimming compared to cycling and running across in age group athletes (6, 25, 63), while at the Olympic, the sex difference in cycling was smaller compared to swimming and running for both elite and age group athletes (47). Table 5 summarizes the key findings of studies investigating the sex differences in performance in the split disciplines.

Table 5. Overview of key findings from studies investigating sex differences in the split disciplines’ performance in different triathlon distances.
The differences across triathlon distances can be attributed to factor such as pacing strategies (34), competition density (70), and variations in training and experience levels (22, 77). In contrast, a more significant sex difference in cycling compared to running and swimming was found in an investigation of the IRONMAN® races between 2002 and 2022 (60). The contrasting findings on sex differences in triathlon disciplines may be explained by methodological differences, course and environmental factors (78, 79), participation rates and competitive depth (70).
The following studies have separately focused on performance in ultra-distance swimming, ultra-cycling, and ultra-running separately. In terms of swimming performance, Knechtle et al. demonstrated that women can outperform men in ultra-swimming events such as the “Manhattan Island Marathon Swim” between 1983 and 2013. The best women were −12%–14% faster than the men in a 46-km open water ultradistance race with temperatures under 20 degrees (80). Other studies have similarly suggested that women can achieve comparable or even superior performance to men in ultra-swimming (81–83). A review by Knechtle et al. showed that women were ∼0.06 km/h faster than men in open-water long-distance swimming events of the “Triple Crown of Open Water Swimming” (“Catalina Channel Swim”, “English Channel Swim” and “Manhattan Island Marathon Swim”) (84). An explanation for this could be women's greater ability to metabolize fat, the better hydrodynamics, and the more even pacing strategy compared to men, which may be advantageous, especially during prolonged swimming competitions (85).
Several studies have also shown a significant decrease in the sex difference in open-water ultra-distance swimming performance over the last years (81, 83, 86, 87). Additionally, a decrease in sex differences with increasing distance has been noted in shorter events. Tanaka et al. demonstrated a gradual narrowing of the sex gap in swimming with extended distances. While the difference was 19% at 50 m, it decreased to 11% at 1,500 m (88). In contrast, other studies showed no changes in sex difference in short distance (89) and ultra-distance swimming (90) over the years.
In ultra-cycling, Baumgartner et al. showed that men were faster than women for race distances between 100 and 500 miles (169.9 km and 804.7 km) in most of the years from 1996 to 2018. The sex difference was greatest in 100-mile races, while it was able to be reduced in the longer distances (200-, 400-, and 500-mile races) (91).
Similar results have also been observed in ultra-running. According to a recent analysis of ultra-running, sex differences decreased with older age and longer distance, while in 100-mile races the difference was 4.41% and in 50-mile races 9.13% (92).
Between 1988 and 2007, women improved their Hawaii IRONMAN® marathon time by 0.8 min per year, while men's times remained constant (13). It appears that women have narrowed the gap to men the most in the marathon running during the IRONMAN® (7). From 1985 to 2004, women's marathon performance improved nearly threefold greater than the rate observed in men (53). Notably, the sex difference in the marathon run of “IRONMAN® Hawaii” aligns that of the “New York Marathon”, suggesting that swimming and cycling factors do not exacerbate the sex gap in running (13).
Nevertheless, women are unable to match men in ultra-running (93, 94) and ultra-cycling (95, 96). A study investigating performance and sex differences in ultra-triathlons between 1978 and 2013 for the three fastest finishers ever revealed that as the distance increases, sex differences in performance remained stable with increasing distance, except in the swimming split where the sex difference increased (64). In contrast to the studies mentioned earlier, this research demonstrated that the sex difference in swimming amplified with distance (64). One plausible explanation for this phenomenon is the athlete's background. Triathletes must compete in three different sports, and each athlete may have a unique background. Many triathletes might have more experience in running or cycling than in swimming (64). Considering the established correlation between performance in cycling and running with success in ultra-triathlons (97, 98) as well as in other distances (14, 99–101), athletes benefit from their experience in these areas in particular.
3.2.4 Predictive variables for race performance
Research studies vary on which discipline is the optimal predictor of overall triathlon performance. There is disagreement as to whether cycling or running is the superior predictor of performance (2, 102, 103). Notably, in the Olympic distance, it has been determined that the running split emerges as the crucial determinant (14, 99). Conversely, Weiss et al. have recently illustrated that cycling demonstrated the strongest correlation with overall race time on the IRONMAN® 70.3 distance, followed by running (100). In a correlation analysis to verify the association level between the overall race time and the split time in IRONMAN® 70.3 age group triathletes have been showed that there were stronger associations of cycling and running with overall race time than swimming and a more negligible difference in swimming performance between women and men (104). A study examining 43 IRONMAN® triathletes (27 men, 16 women) revealed that among men, cycling exhibited the highest correlation with overall race time, whereas among women, running and cycling displayed approximately equivalent associations (101). However, no study has established swimming as a predictor of performance. The contribution of swimming split times to the overall race time is notably lower compared to cycling and running in ultra-triathlon (77).
Potential predictive variables for a fast race time for the IRONMAN® distance and ultra-triathlon have been analyzed. The most important predictive variables for a fast IRONMAN® race time were age of 30–35 years (women and men), a fast personal best time in the Olympic distance triathlon (women and men), a fast personal best time in marathon running (women and men), both a high volume and a high speed in training where high volume was more important than high speed (women and men), low body fat, low skin-fold thicknesses and low circumference of upper arm (only men), and origin from the United States of America (women and men) (15). Knechtle et al. also found that the origin of the athlete and the age group were the most important predictors in IRONMAN® races (105). For ultra-triathlon, the most important predictive variables were male sex, low body fat, age of 35–40 years, extensive previous experience, a fast time in cycling and running but not swimming, and origins in Central Europe (77).
To summarize this section, future studies need to consider the impact of the male-to-female ratio on participation, as this can influence competitive dynamics and the observed performance gap. Recent studies have shown that women are still underrepresented in research (106, 107). Whereas 10 years ago the proportion of women was 39%, today it has risen to 43.95% (48, 106). Additionally, in sports science, there are more male-only (31%) studies than female-only (6%) studies, leading to a knowledge gap in women-specific physiology and performance (107). This indicates that, despite progress, there remains a substantial need for further effort in research to achieve equitable sex representation. Future research should also account for advancements in technology over recent decades, such as improvements in equipment, racewear, and recovery tools, which may have affected the performance of female and male athletes differently. Furthermore, there is limited information on how environmental factors, such as the surrounding temperature, affect the performance in female and male triathletes. Therefore, future studies need to investigate the influence of the environmental conditions on triathlon performance.
3.3 Physiology, morphology, and anthropometry
There is consensus in the literature that maximal oxygen uptake (VO2max) and body composition are key variables associated with performance in longer triathlon distance events (108). It is also well-established that male athletes generally demonstrate superior aerobic performance in various endurance sports compared to female athletes (63, 71).
In Table 6, the key findings from studies examining physiological characteristics in female and male triathletes are summarized.

Table 6. Overview of key findings from studies investigating aspects of physiology in female and male triathletes.
3.3.1 Maximum oxygen uptake (Vo2max)
In literature, there is consensus that female athletes tend to exhibit relatively lower VO2max values (ml/min/kg) during cycling or running compared to their male counterparts (63, 71). The Table 7 summarizes the values of VO2max from studies that investigated physiological characteristics in triathletes. The mean values in these studies for VO2max were for women in Sprint distance 45.9 ± 2.5 ml/kg/min and in Olympic distance 50 ± 0.6 ml/kg/min, and for men 51.4 ± 1.0 ml/kg/min and 57.6 ± 3 ml/kg/min, respectively. Compared to a study, where 33 female IRONMAN® triathletes were measured, the values for VO2max in Sprint and Olympic distances were smaller (109). It should be noted that the sample sizes of these studies were small and the level of the participants and the used measurements were different.

Table 7. Values for VO2max and anaerobic threshold from studies investigating physiological variables.
VO2max is limited by the cardiovascular capacity to transport oxygen, in the vast majority of people (110), showing a strong relationship with total hemoglobin (111) and maximal stroke volume (112). The discrepancy of VO2max is frequently ascribed to central factors, such as women's smaller hearts and lower hemoglobin mass, which may limit their capacity to supply oxygen to skeletal muscles (113, 114). Further variables affecting VO2max include blood cell mass, and hematocrit (110). Typically, women present lower values for these parameters (115–117). When comparing women's hemoglobin levels with those of “age and race-matched” men, women consistently demonstrated 12% lower mean hemoglobin levels irrespective of iron status (111, 118). Women's VO2max values adjusted to body mass are typically ∼20%-25% lower than men's (119, 120). A recent study by Martins et al. found no significant difference between women and men in VO2max values when adjusted for lean mass, even at submaximal training intensities (120). This parameter reflects muscular aerobic capacity and is limited by peripheral conditions such as capillary density, mitochondrial content in muscles, and enzyme levels in mitochondria (121). Given the absence of disparities in VO2max values adjusted for lean mass between the sexes, it can be inferred that skeletal muscles in female and male athletes possess equivalent oxygen extraction capabilities (120). However, some studies have reported differences in VO2max values adjusted for lean mass (122, 123). The discrepancies in findings from previous studies may be attributed to variations in the level of physical conditioning among female and male participants, small sample sizes, the methodologies used to assess lean mass, and the specialization of event distance (e.g., focusing on training for Olympic or IRONMAN® distances) (19, 120).Given that the performance gaps between the sexes are smaller than the discrepancy in VO2max (124), other physiological factors significantly influence performance (120).
3.3.2 Anaerobic threshold
In addition to VO2max as an important parameter for performance, the lactate threshold also correlates with endurance performance (124). In triathletes, female athletes showed higher anaerobic thresholds than male athletes (17, 71). Similar results were found for athletes in the Olympic distance triathlon race, where Fernandes et al. (2023) studied 41 triathletes (22 men and 19 women) showing that the female athletes run at a higher percentage of the ventilatory threshold than the male athletes (27). Values for the anaerobic threshold listed in Table 7 are based on studies examining physiological factors in triathletes. In the different studies, a cardiorespiratory maximal test on a treadmill or a cycling ergometer were performed to identify the ventilatory threshold. The ventilatory threshold was identified by an increase in the ventilatory equivalent for oxygen without a corresponding rise in the ventilatory equivalent for carbon dioxide along with an increase in the partial pressure of exhale oxygen. The mean values in these studies for ventilatory threshold were for women in Sprint distance 69.9 ± 6.3% and at the Olympic distance 78.3 ± 2.8%, and for men 68.8 ± 6.2% and 74.3 ± 0.3% of VO2max, respectively.
In most of the studies investigating anaerobic threshold values for ventilatory threshold were available. Quittmann et al. (2022) measured the blood lactate in 24 runners and 20 triathletes with a total of 15 female and 29 male participants. They found a higher fractional utilization of VO2max at lactate threshold according to a fixed lactate concentration of 4 mmol/L (onset of blood lactate accumulation) in women (125).
A key factor in achieving a high lactate threshold is the capacity of mitochondria in muscles to increase their volume in response to training (126). Endurance training has been demonstrated to enhance lactate threshold (127, 128). Importantly, lactate threshold has been shown to correlate significantly with performance in prolonged running events like the marathon (124). Elite athletes can sustain 80%–90% of their VO2max for prolonged periods with a minor rise in blood lactate (124). Similar findings to triathletes were found in runners. In a study involving 75 long-distance runners (37 men and 38 women), slightly higher lactate thresholds (2.5%) were found in women than in men (129).
3.3.3 Body composition
Moreover, body composition significantly impacts endurance performance. Body fat percentage has emerged as a crucial predictive factor in events such as the IRONMAN® 70.3 (16), IRONMAN® (21, 77), and ultra-triathlon distances (77). Table 8 shows the key findings of the studies investigating the aspects of body composition in female and male triathletes.

Table 8. Overview of key findings from studies investigating aspects of body composition in female and male triathletes.
Regarding the association between body fat percentage and race performance, Knechtle et al. found a correlation between body fat percentage and overall race time in IRONMAN® distance events, but only in male participants (22). This observation was consistent with findings from another study (21). However, no significant correlation between anthropometric measures and performance was identified in Triple Iron (97, 98) and Deca Iron ultra-triathlon (130) events. It is worth noting, however, that these studies focused exclusively on male athletes.
Sex differences in body composition are notable among IRONMAN® triathletes, with men exhibiting an average body fat percentage of 14%, compared to 23% in female counterparts, measured with the anthropometric method using the skin-fold calliper (21). In addition to their lower body fat percentage, men typically exhibit greater muscle mass and muscle strength compared to women (21). In 27 male and 16 female IRONMAN® triathletes, it was shown that men had 41 kg of muscle mass, while women showed a muscle mass of 28 kg (21). Furthermore, women generally have lower body mass and height (71), although no discrepancies were observed in trunk fat percentage. However, women showed a higher proportion of gynoid fat mass (71). Table 9 summarizes the values of body mass in kilograms and body fat percentage from studies investigating anthropometric variables in triathletes. The values differ between the length of the race. The mean body weight (63.7 ± 0.2 kg in Sprint vs. 59.2 ± 0.9 kg in Olympic, 60.2 ± 0.8 kg in IRONMAN®) and the body fat percentage (28.1 ± 0.1% in Sprint vs. 22.8 ± 0.6% in Olympic, 23.1 ± 0.5% in the IRONMAN®) in women was greatest in Sprint distance. It must be noted that different methods were used to asses body composition, with DEXA (Dual Energy x-ray Absorptiometry) applied for sprint and Olympic distances, and anthropometric with a skin-fold calliper in the studies investigating the IRONMAN® distance. In each length, the mean values for body weight in women were smaller compared to men and the body fat percentage was higher. However, it is difficult to compare the studies as the level of the participants was different, the sample sizes were small, and varying methods of body composition measurement were used.

Table 9. Values for body mass, and body fat percentage from studies investigating anthropometric variables.
The higher body fat percentage in women can confer advantages in the swimming discipline, as it increases buoyancy in water (63), potentially contributing to the smaller sex difference observed in this discipline (131). Body fat might be related to greater substrate efficiency in ultra-endurance sports, where a prolonged exercise would induce the recruitment of fat stores (132). Moreover, body fat distribution is associated with performance (133), with higher android fat percentage reducing buoyancy and swimming speed (134). Additionally, increased body fat percentage provides better insolation in cold water (135), benefiting women's swimming performance, particularly in open-water long-distance swimming in cold temperatures (135, 136). However, during a 1.5 km swimming distance with a water temperature of around 20°C, women's higher body fat percentage does not confer advantages (47).
In addition to the lower muscle mass in female triathletes (21), studies indicated that women experience the loss of muscle mass and strength at an earlier stage than men (53, 137). This observation agreed with those in general population, where women had shorter limb levers, weaker bones and less muscle mass and muscle strength (138).
Research has also shown that women exhibit lower levels of muscular fatigue and faster recovery during endurance training (113). In controlled studies, it has been shown that women generally exhibit greater fatigue resistance than their male counterparts (139, 140). Even during high-intensity interval training (HIIT), Hottenrott et al. suggested that women may demonstrate greater fatigue resistance and enhanced metabolic recovery (141). This lower fatigue may be attributed to the higher proportion of type 1 muscle fibers in women (142).
To conclude this section, future studies investigating VO2max should adjust measurements to lean body mass, ensuring more accurate comparisons between female and male athletes. These studies would benefit from larger sample sizes and should include athletes of comparable skill levels, using standardized measurement protocols to ensure consistency. Additionally, future studies need to investigate running economy in female triathletes, as it was found to be a determinant of performance (143). Given known sex differences in fatigue resistance, biomechanics, and substrate utilization, research in this area could provide important insights for optimizing performance and training strategies for triathletes. Furthermore, there are no consistent findings on the performance during the menstrual cycle in other endurance sports (144–146). In triathlon-specific research, the effects of the menstrual cycle on triathlon performance are still scarce. Given the unique demands of the sport, further research is needed to understand how different menstrual cycle phases impact performance, recovery, and training in female triathletes. Understanding hormonal influences could help optimize training and race strategies for women in triathletes.
3.4 Aspect of age
The literature search identified a total of 20 studies that focused on age in triathletes. The Table 10 presents the key findings of studies investigating the effect of age on performance in triathlon and the age of peak performance in female and male triathletes. It is widely acknowledged that physiological, morphological, and functional capacities change with age (147). Furthermore, sex differences in endurance performance alter with increasing age (6, 7, 104). Multiple studies provide evidence of age-related effects on performance. Therefore, comprehending the age at which peak performance is achievable holds significant importance for athletes and their coaches regarding career strategizing (148).

Table 10. Overview of key findings from studies investigating the effect of age on performance in triathlon and the age of peak performance in female and male triathletes.
3.4.1 Age of peak performance
The age of peak performance in IRONMAN® triathlons is between 25 and 39 years for both women and men (13, 25, 72). Knechtle et al. investigated the specific ages associated with peak performance across various distances (148). They determined that for women, the age of peak performance was 26.6 ± 4.4 years in the Olympic distance, 31.6 ± 3.4 years in the IRONMAN® 70.3 distance, and 34.4 ± 4.4 years in the IRONMAN® distance. The age of the annual top 10 women and men remained unchanged over the period from 2003 to 2013 in the IRONMAN® 70.3 and IRONMAN® distances (148). However, a study of the “IRONMAN® Hawaii” from 1983 to 2012 revealed a trend of increasing age among the annual top 10 performers alongside performance improvement. For men, the age of the annual top 10 increased from 27 ± 2 to 34 ± 3 years, and for women from 26 ± 5 to 35 ± 5 years (24). Overall, it seems that the age of peak triathlon performances increases with increasing race distance from the Olympic distance to IRONMAN® distance.
Regarding distances longer than the IRONMAN® distance, it was observed that the average age of finishers in the Deca Iron ultra-triathlon is notably higher than in the Triple Iron ultra-triathlon. Furthermore, the average age of finishers increased from 1992 to 2010 in both ultra-distances (149). Similarly, in ultra-marathons, it has been demonstrated that the age at which peak performance is attained is higher for longer distances (73, 74, 150, 151).
3.4.2 Age-related performance decline
As illustrated in the preceding section, there has been a notable rise in the number of master athletes. Alongside this surge in participation among master athletes, remarkable improvements in performance have been observed, while the performance of athletes under the age of 40 years has remained relatively static (24, 37, 47, 152). It appears that athletes in younger age brackets have reached a plateau in performance across the IRONMAN® distance (24, 37). However, performance begins to decline with age (37, 137).
Table 11 summarizes the key findings of studies investigating the age-related performance decline in female and male triathletes.

Table 11. Overview of key findings from studies investigating the age-related performance decline in female and male triathletes.
Puccinelli et al. have recently shown that female amateur triathletes in the “IRONMAN® Hawaii” present a similar pattern in age-related performance decline as their male counterparts. No differences in overall race time were found in the age groups from 25 to 29 years until 40–44 years. Female and male triathletes broke this plateau trend in the 45–49 age group, and the times for older age groups increased progressively (153).
In triathlon, the age-related performance decline appears to be contingent on the discipline involved (1, 149). Cycling showed a lesser decline compared to swimming and running (154). This discrepancy can be explained by the physiological and mechanical differences between cycling, running, and swimming, such as the transition from a weightless to a weight-bearing activity and the shift from a concentric muscle action in cycling to a stretching and shortening activity with eccentric contractions in running (155). Additionally, differences in training stimuli may explain the lower age-related performance decline in cycling compared to running and swimming (154, 155). Furthermore, it has been observed that the extent of the age-related decline varies depending on the race distance, with a more significant decline in cycling and running performance observed in the IRONMAN® distance compared to the Olympic distance (154).
Potential explanations for the performance improvements observed in master athletes may include increased participation rates, expanded training opportunities tailored to older individuals and a heightened competitive drive (37). Furthermore, analogous performance improvements have been observed among master athletes in other sporting domains, such as swimming (156) and ultra-marathon running (157).
The age-related decline in performance was also demonstrated in other endurance sport, for example in swimming (88, 158) and running (46). This decline typically became noticeable around the ages of 40–50 years, exhibiting a moderate progression until the age of 70, followed by an exponential decrease in endurance performance (46, 88, 158). Various factors contribute to the age-related decline in endurance performance. Age serves as a limiting factor for VO2max (159, 160). The progressive reduction in VO2max is the primary mechanism driving performance decline with age (161). Additionally, there is a concurrent loss of muscle mass with aging, which tends to occur faster in women than men (162, 163).
Further reasons for the more significant decline in performance with increasing age may encompass lifestyle adjustments, alterations in training regimens characterized by reduced volume and intensity, and dietary considerations among older athletes (147, 161, 164–167). The natural aging process can either be hastened or decelerated by lifestyle choices. The training status of master athletes emerges as a critical modulator of performance deterioration with advancing age. Changes in physiological functions and running performance with age are closely related to the extent of running training (167).
3.4.3 Changes in sex differences in performance with age
An increase in sex differences with age at the IRONMAN® distance is evident. In Table 12, the key findings of studies investigating the changes in sex differences in performance with age in female and male triathletes are summarized. Lepers & Maffiuletti demonstrated that sex gaps in overall performance significantly widened with increasing age, particularly beyond 55 years of age, while remaining relatively stable before the age of 55 (25). Male athletes aged 60 exhibited a 27% slower pace than triathletes aged 30–40 years, whereas the difference for women was 38% (25). Additionally, Gries et al. showed an increase of the sex difference to 20% in the age group of 65-69 years (168).

Table 12. Overview of key findings from studies investigating the changes in sex differences in performance with age in female and male triathletes.
Explanations for this increase may encompass diverse physiological influencing factors (25) and the earlier onset of muscle mass loss in women (162, 163). Lepers et al. also noted the diminished participation of women in older age cohorts, which could contribute to a heightened sex difference (25). Moreover, hormonal differences pre- and post-menopause could further explain the more conspicuous age-related decline in performance among women (169). In addition to the pre- and post-menopause changes, female triathletes may also discover barriers that prevent them from returning to an exercise routine, including muscle weakness, fatigue, depression, and physical changes (170). The postpartum period is influenced by the number of births, the interval between births, the type and duration of labor and delivery as well as the length of time spent breastfeeding (170).
Future studies should explore the impact of pregnancy and childbirth on female triathletes, particularly how prolonged break from training affects recovery and fitness return. Additionally, research is needed on menopause-related hormonal changes and their effects on endurance, muscle function, and recovery, to develop training strategies tailored to aging female athletes.
3.5 Training, experience, pacing, nutrition and motivation
3.5.1 Training and experience
Training (22, 171) and experience in triathlon (15, 77, 172, 173) are central factors influencing performance in triathlon competitions. The main conclusions of the studies examining the elements of experience and training in female and male triathletes are compiled in Table 13.

Table 13. Overview of the key findings from studies investigating the aspects of training and experience in female and male triathletes.
3.5.1.1 Training
In a study with 27 male and 16 female nonprofessional IRONMAN® triathletes, the weekly average training volume was 14.8 ± 3.2 h for men and 13.9 ± 3.4 h for women (22). The most training was spent in cycling with 8.0 ± 2.0 h for men and 7.5 ± 2.4 h in women (22). Similar results were found in 166 male and 224 female long-distance triathletes with a weekly training volume of 16 ± 4.9 h in men and 13.6 ± 5.5 h in women (30). In contrast, for Olympic distance triathlon the training volume per week was 8 h and 48 min (mean for 6 male and 5 female recreational-level triathletes) (174).
Weekly training duration impacts IRONMAN® performance differently across sexes. Research indicates that while weekly training volume significantly correlates with the total race time in women, this association is not observed in men (22, 101). Interestingly, neither sex showed a correlation between training speeds in swimming, cycling, and running and the actual speeds in these disciplines during the race (22). In the context of ultra-triathlons, training distance appeared to outweigh training pace in its influence on performance (175–177).
An older study highlighted the importance of training parameters such as distance, time, and experience over anthropometric factors in predicting the performance of female triathletes in short-distance races (178). Despite similar training volumes between the sexes, men tend to swim and cycle faster in training compared to women (101).
Triathletes showed a strong focus on training at low- to moderate- intensities below lactate threshold (179, 180). For example, a world-class female Olympic distance triathlete completed 74% of her swim training, 88% of her cycling training, and 85% of her running training at intensities below her individual lactate threshold (179). Also, at IRONMAN® distance, an improved performance has also been linked to extended duration of training at low to moderate intensities (180). This is also evident in other sports, including swimming (181), cycling (182), and running (183).
A recent narrative review looked at the effect of altitude training (184). The live high-train low method, meaning live at a high altitude (1,250–3,000 m) and train at low altitude or sea-level (0–1,200 m), has been used across a range of endurance-based disciplines (185). Studies have shown significant benefits for performance (186, 187).
3.5.1.2 Experience
Previous participation in triathlon events (16) and achieving personal best times in both IRONMAN® and shorter distances like the Olympic distance (22, 188–190) have been robustly linked to faster IRONMAN® race times (15). Moreover, achieving a personal best time in a marathon has emerged as a strong predictor of performance in IRONMAN® races for both women (189) and men (190). In ultra-distances, the significance of race experience diminishes compared to shorter distances (172), contrary to the findings of Herbst et al. (191). Specifically, Herbst et al. found associations between the number of completed Triple Iron ultra-triathlons and personal best times in a Triple Iron ultra-triathlon with overall race time in a Deca Iron ultra-triathlon (191). However, studies across other endurance disciplines (running, cycling) have shown that the number of races completed does not correlate with overall race time (192–195).
Personal best time in an IRONMAN® triathlon is a robust predictor of race time in both women and men (22). Notably, Knechtle et al. revealed that female winners of the “IRONMAN® Hawaii” exhibit greater prior experience in IRONMAN® races and shorter distances than male winners (15). Given the association between personal best time at the IRONMAN® and race performance across sexes, it can be inferred that race experience holds greater significance than anthropometric parameters and training volume (22).
3.5.2 Pacing
Pacing is a crucial element in endurance performance (196) and has been extensively studied across various triathlon distances (34, 197, 198). In IRONMAN® triathlon, pacing, alongside numerous other factors such as age, previous experience, sex, origin, anthropometry, physiology, and performance in individual disciplines, emerges as a significant predictor for race outcomes (15). Table 14 provides a summary of the main conclusions from the research on the pacing characteristics of female and male triathletes.

Table 14. Overview of the key findings from studies investigating the aspects of pacing in female and male triathletes.
To mitigate premature fatigue resulting from overly aggressive cycling or running, athletes must effectively manage their metabolic energy expenditure, typically achieved through strategic adjustments of speed and intensity to optimize performance (199).
Six distinct pacing strategies have been identified: negative pacing (gradually increasing speed), positive pacing (gradual slowing), all-out pacing (maximal speed exertion), even pacing (maintaining a consistent speed), parabolic-shaped pacing (combining positive and negative pacing across race segments), and variable pacing (marked fluctuations in speed) (196). Numerous studies have shown that positive pacing is a viable strategy across various races and disciplines (200–202). Notably, elite female and male triathletes competing in the “IRONMAN® Hawaii” commonly employed positive pacing strategies during both cycling and running segments. In six out of thirteen races analyzed, female athletes notably reduced their cycling speed to a greater extent than their male counterparts, with no significant sex differences observed in speed adjustments during the running segment. (33)
In a study conducted on the “IRONMAN® Hawaii” event in 2022, it was found that male athletes displayed a predominantly negative pacing strategy during the cycling split, while female athletes maintained a more consistent pacing approach (203).
Studies have shown that men often commence the swim and cycling segments of draft-legal Olympic races with a relatively aggressive initial pace compared to women (204, 205). Despite physiological and morphological disparities between the sexes and the weight-bearing aspect of running (7, 206), both female and male triathletes typically demonstrate similar positive pacing patterns during the running segment of draft-legal Olympic-distance triathlons (204, 207).
3.5.3 Nutrition
In endurance events, appropriate fueling is crucial for both safety and peak performance (208). Carbohydrates remain the primary energy source during moderate- to high intensity exercise (209), and recommendations for intake are typically based on event duration (210). However, a narrative review of Lodge et al. showed that the average carbohydrate intake in female athletes falls below current recommendations (211).
Several studies highlight that low energy availability (LEA) is a fundamental factor contributing to the Female Athlete Triad, which involves the interplay between eating disorders, irregular or absent menstrual cycles, and low bone mineral density (212–214). A study investigating low energy availability (LEA) in 30 female triathletes found that 23.3% had a monthly cycle disorder and that 20% of the participants either had, at the time of the study, or had had in the past monthly cycle disorders that could indicate an immediate LEA (215). This issue is often underestimated by both athletes and coaches, highlighting the need for greater awareness of the health-performance balance in endurance sports. Therefore, it is important to audit current guidelines for carbohydrate intake to include sport-specific recommendations and strategies for female athletes to support their health and performance (211). Furthermore, it should be noted, however, that most of the studies were not specific to triathletes, highlighting the need for triathlon-specific data on carbohydrate intake in female triathletes.
Hydration strategies also present sex-related risks, particularly with regard to exercise-associated hyponatremia (EAH) (216). EAH occurs when blood sodium levels drop below 135 mmol/L, often due to excessive fluid intake and inadequate release of vasopressin during prolonged exercise, such as an IRONMAN® race (216). This condition can lead to symptoms ranging from mild nausea and confusion to severe complications like seizures or cerebral oedema, particularly in endurance athletes. Female athletes, slower race times, extreme hot or cold external temperatures, and use of nonsteroidal anti-inflammatory drugs have been associated with a higher EAH risk (216, 217).
A study investigating EAH in female and male IRONMAN® triathletes between 1989 and 2019 confirmed that women are more likely to be hyponatremic during ultra-endurance exercise. It was found that 29.7% of women who received bloodwork testing were hyponatremic, compared to 21.2% of men. Furthermore, the women receiving bloodwork showed significantly lower serum sodium values (137.4 mEq/L vs. 139.7 mEq/L in men) (218).
3.5.4 Motivation and other psychological factors
The preparation for a triathlon race requires a major commitment from the athletes. The load of trainings could influence their behavioral and psychological characteristics (219). Motivation varies between the sexes. Women's motivation often revolves around goals such as fat reduction, fitness improvement and social interaction (220–222), whereas competition and winning are more significant motivators for men. Furthermore, research by Dolan et al. suggests that most participants engage in endurance sports for reasons related to health, enjoyment, social engagement, and personal accomplishments rather than for competitive purposes (31). Interestingly, Lopez-Fernandez et al. found that female and male triathletes competing at the international level exhibit similar motivation profiles. No sex differences in sport motivation were found based on the competition level and age (223).
Table 15 summarizes the key findings of studies investigating the aspects of motivation in female and male triathletes.

Table 15. Overview of the key findings from studies investigating the aspects of motivation in female and male triathletes.
A study investigated the psychological profile of amateur triathletes over a training period of six months prior to and after a long-distance triathlon(219). They found that the participants were more harmonious than obsessive with their triathlon's passion. Positive emotions increased until the sixth month and were significantly higher than the negative emotions (219).
Differences in psychological characteristics have been found between modalities and level of professionalism (224). Professional triathletes showed higher scores than amateur triathletes in all psychological dimensions assessed (stress control, influence of performance evaluation, motivation and mental skills). No significant differences between men and women were found. Additionally, the study showed that triathletes scored higher than cyclists in all the variables with a particularly strong effect observed in mental skills and motivation (224).
To conclude this section, future studies need to examine the factors influencing women's motivation in triathlon, including the effect of performance pressure, the presence of role models, and social influences on participation and performance. Studies on the nutrition of female triathletes are scarce. Research should therefore focus on nutrition/fluid intake and energy availability specifically for female athletes. Additionally, studies should investigate training adaptations based on the menstrual cycle to optimize performance, recovery and overall health in female triathletes. Also, the number of female participants in triathlon research should be increased and brought closer to that of men to draw safe conclusions on sex differences.
4 Conclusion
In conclusion, this narrative study highlights the specific problems and opportunities experienced by women in the sport of triathlon. Sex differences in participation and performance varied across distances. In female triathletes, especially in master triathletes, the participation increased and the performance improved. A significantly lower VO2max and a higher lactate threshold was showed in female triathletes. While the body mass was lower, the body fat percentage was higher in women. The age of peak performance in IRONMAN® triathlons is achieved between 25 and 39 years for both women and men. Personal best time in a marathon and best time in previous triathlons proved to be strong predictors of performance in IRONMAN® races.
A limitation of this narrative review is the absence of a structured assessment of study quality and potential risk of bias, particularly regarding the physiological part. Although not required for narrative reviews, such assessments are considered best practice and could have strengthened the credibility of the findings. Moreover, the lack of formal quality appraisal may limit the ability to weigh the strength of evidence across studies, especially when sample sizes are small or methodologies vary substantially. Additionally, selection bias may have occurred due to the inclusion criteria and the manual selection of studies, potentially influencing the balance of represented findings.
While there is a growing body of research on female athletes in endurance sports, most studies still focus primarily on male athletes, leading to a gap between the sexes in the currently available data. Future research should therefore aim to balance the representation of female and male athletes in the study cohorts, ensuring that the findings are relevant to both sexes. In this way, researchers can develop more comprehensive guidelines that account for the unique physiological and psychological factors influencing women in triathlon, ultimately promoting more effective and inclusive training practices.
The effect of menstruation on training and performance is an important topic that requires further research. In particular, future studies should consider longitudinal designs that track individual athletes across multiple menstrual cycles to better understand fluctuations in performance, recovery, and injury risk. Such research should also account for hormonal contraceptive use, menopausal status, and related hormonal variations.
Additionally, studies need to focus more on the impact of pregnancy and childbirth on female triathletes, as well as the influence of menopause-related hormonal changes on performance, muscle function, recovery, and risk of injury. Furthermore, the inclusion and representation of transgender athletes is another critical area given the evolving policies surrounding gender identity in competitive sports. Future studies should aim to address both the participation and performance outcomes of transgender athletes in order to contribute to a more inclusive understanding of gender in triathlon.
Author contributions
ML: Conceptualization, Writing – original draft. PN: Writing – review & editing. VS: Writing – review & editing. MW: Writing – review & editing. PF: Writing – review & editing. MA: Writing – review & editing. TR: Writing – review & editing. SD: Writing – review & editing. IC: Writing – review & editing. BK: Writing – review & editing.
Funding
The author(s) declare that no financial support was received for the research and/or publication of this article.
Conflict of interest
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
Generative AI statement
The author(s) declare that no Generative AI was used in the creation of this manuscript.
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Keywords: ironman, sex differences, performance, endurance, ultra triathlon, training, female triathletes
Citation: Loosli M, Nikolaidis PT, Scheer V, Wilhelm M, Forte P, Andrade M, Rosemann T, Duric S, Cuk I and Knechtle B (2025) Women in the triathlon—the differences between female and male triathletes: a narrative review. Front. Sports Act. Living 7:1567676. doi: 10.3389/fspor.2025.1567676
Received: 28 January 2025; Accepted: 19 May 2025;
Published: 6 June 2025.
Edited by:
Gregoire P. Millet, Université de Lausanne, SwitzerlandReviewed by:
Guro Strøm Solli, Nord University, NorwayTomasz Kowalski, Institute of Sport, National Research Institute, Poland
Copyright: © 2025 Loosli, Nikolaidis, Scheer, Wilhelm, Forte, Andrade, Rosemann, Duric, Cuk and Knechtle. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
*Correspondence: Beat Knechtle, YmVhdC5rbmVjaHRsZUBoaXNwZWVkLmNo
†ORCID:
Michèle Loosli
orcid.org/0009-0008-5531-0168
Pantelis T. Nikolaidis
orcid.org/0000-0001-8030-7122
Volker Scheer
orcid.org/0000-0003-0074-3624
Matthias Wilhelm
orcid.org/0000-0003-4541-3995
Pedro Forte
orcid.org/0000-0003-0184-6780
Marilia Andrade
orcid.org/0000-0002-7004-4565
Thomas Rosemann
orcid.org/0000-0002-6436-6306
Sasa Duric
orcid.org/0000-0002-3392-0087
Ivan Cuk
orcid.org/0000-0001-7819-4384
Beat Knechtle
orcid.org/0000-0002-2412-9103