David T. Martin,1 Brian McLean,1 Cassie Trewin,1 Hamilton Lee,1 James Victor2 and. Allan G. Hahn1. 1 Australian Institute of Sport, Sport Medicine and Sport ...
REVIEW ARTICLE
Sports Med 2001; 31 (7): 469-477 0112-1642/01/0007-0469/$22.00/0 © Adis International Limited. All rights reserved.
Physiological Characteristics of Nationally Competitive Female Road Cyclists and Demands of Competition David T. Martin,1 Brian McLean,1 Cassie Trewin,1 Hamilton Lee,1 James Victor2 and Allan G. Hahn1 1 Australian Institute of Sport, Sport Medicine and Sport Science Centre, Belconnen, Australian Capital Territory, Australia 2 Australian Institute of Sport, National Women’s Road Cycling Program, Belconnen, Australian Capital Territory, Australia
Contents Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1. Characterising Elite Cyclists . . . . . . . . . . . . . . . . . . . . . . . 2. Defining ‘Elite’ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3. Women’s Road Cycling: Historical Development . . . . . . . . . . 4. Characteristics of Elite Female Road Cyclists . . . . . . . . . . . . . 4.1 Age, Height, Mass and Body Composition . . . . . . . . . . . 4.2 Measures of Aerobic Fitness . . . . . . . . . . . . . . . . . . . . 4.3 Measures of Anaerobic Power and Capacity . . . . . . . . . 5. Demands of Women’s International Road Cycling Competition . 5.1 Power Output Demands of Women’s World Cup Competition 6. Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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There are few published data describing female cyclists and the studies available are difficult to interpret because of the classification of athletes. In this review, cyclists are referred to as either internationally competitive (International Cycling Union world rankings provided when available) or nationally competitive. Based on the limited data available it appears that the age, height, body mass (BM) and body composition of women cyclists who have been selected to the US and Australian National Road Cycling Teams from 1980 to 2000 are fairly similar. Female cyclists who have become internationally competitive are generally between 21 to 28 years of age, 162 to 174cm, 55.4 to 58.8kg and 38 to 51mm (sum of 7 skinfolds) corresponding to 7 to 12% body fat. The lower BM and percentage body fat are traits unique to the most competitive women. Internationally competitive women cyclists also possess a slightly superior ability to produce a high absolute power output for a fixed time period and a noticeably greater ability to produce power output relative to BM. In Women’s World Cup races, successful women (top 20 places) spend more time >7.5 W/kg (11 ± 2 vs 7 ± 2%, p < 0.01) and less time 65 ml/kg/min] may not have a history of winning at the highest level. Therefore, instead of choosing a strict laboratory or performance criteria that must Sports Med 2001; 31 (7)
Women’s Road Cycling
be met to classify an athlete as elite, it may be more informative for scientists to simply make reference to performance capabilities when the research population is being described [i.e. International Cycling Union (UCI) ranking, major wins]. A complicating factor in the ability to accurately classify the competitiveness of a road cyclist is the fact that cyclists can have different goals during a race that range from being a good domestique (i.e. team helper) to winning the World Championships. As a result, some very competitive women cyclists do not have a UCI ranking that is truly reflective of their ability. Regardless of these limitations, if the physiological characteristics of internationally competitive athletes are well described, then researchers can attempt to recruit individuals with similar laboratory fitness parameters to better understand how competitive athletes would respond to a treatment. These recommendations, if adopted, could help sport scientists present their data in a more meaningful context that will eventually lead to a better understanding of the physiological and anthropometric requirements for success in the sport of cycling at the highest level. 3. Women’s Road Cycling: Historical Development The UCI is a world sports governing agency responsible for internationally competitive cycling events. A recent UCI classification (July 2000) of elite women road cycling nations indicated that of the 36 nations receiving UCI points from female cyclists, only 9 nations have 5 or more cyclists ranked in the top 100 in the world and of these there are 8 nations with 3 or more female cyclists ranked in the top 50 in the world. In July 2000 the following nations had 2 or more female cyclists ranked in the world top 20: Australia (n = 2), Germany (n = 4), Lithuania (n = 2), the Netherlands (n = 2) and Russia (n = 4).[12] It is important to note that the description ‘national team member’ does not necessarily indicate that an athlete is internationally competitive as there are many countries with national team cyclists that are unable to win or place highly in international races. The term ‘national © Adis International Limited. All rights reserved.
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team member’ can therefore be used to describe female cyclists with markedly different performance capabilities and is not particularly descriptive with regard to competitive capability. In 1999 the UCI introduced registered women’s trade teams. There are currently 16 professional women road cycling teams and each employs between 6 to 12 cyclists. For the year 2000 cycling season ≈160 women cyclists held employment contracts and were identified as professional cyclists. Unlike the lucrative contracts offered to male road cyclists, top female cyclists currently receive between $US40 000 to 60 000 per year in addition to prize money and individual sponsorship bonuses. The biggest professional women’s trade teams operate on annual budgets between $US500 000 to 1 million. The ability of the women on these teams to perform at the international level is highly variable. Some women on a professional team will be ranked among the top 10 female cyclists in the world whereas others will be ranked outside the top 200. Thus, similar to the term national team cyclists the term ‘professional cyclists’ can be used to describe a group of athletes with greatly differing performance capabilities. 4. Characteristics of Elite Female Road Cyclists Table I presents data describing the physiological characteristics of elite female road cyclists. While these data[13-15] highlight some interesting characteristics associated with nationally competitive US female cyclists between 1980 and 1996, they do not allow for a clear understanding of what is required to be internationally successful as the terminology used and the tests performed are quite variable. For instance, all studies performed a maximal incremental intensity exercise test, but only Wilber and colleagues[15] reported the peak power output attained. Additionally, even though peak power out. put during a VO2max test has been shown to correlate with 20km time trial performance[11] it is likely that this peak power output parameter is influenced by the testing protocol and therefore may not always be meaningfully compared between studies. Sports Med 2001; 31 (7)
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Martin et al.
Table I. Summary of published characteristics of ‘elite’ female road cyclists. Data are presented as mean ± SD Measure
Burke[13]
Pfieffer et al.[14]
Wilber et al.[15]
10
Participants Number
7
16
Description
US National Team
Participants in 1990 Idaho Tour
US National Team
Altitude (m)
1800-2000
Variable
1860
Testing date
1976-1980
2 days before 1990 Idaho Tour
Lead up to 1996 Olympics
Anthropometry Height (cm)
167.7 ± 10.7
171 ± 5
Weight (kg)
61.3 ± 8.5
61 ± 4
60.4 ± 3.6
Body Fat (%)
15.4 ± 4.7
15.7 ± 2.0
11.9 ± 1.8
28 ± 3
26 ± 5
Age (y) . VO2max test Protocol
5 min at 200W, then ↑ 40 Start at 100W, ↑ 25 W/min W/min; cadence fixed at 80 rpm
3 min submax and 1 min max stages; ↑ 25 W/stage
Ergometer . VO2max (ml/kg/min) . VO2max (L/min)
Monark
Lode Excalibur
57.4 ± 6.6
Schwinn Velodyne 64.2 ± 4.0 3.91 ± 0.22
3.58
Peak heart rate (beats/min)
185.2 ± 3.2
333 ± 21
Peak power output (W)
5.4 ± 0.4
Peak power output (W/kg) Anaerobic threshold . VO2 (% max)
83.6 ± 2.7 165 ± 12
Heart rate (beats/min)
3.0 ± 0.6
Lactate (mmol/L)
224 ± 8
Power output (W)
. . SD = standard deviation; VO2 = oxygen uptake; VO2max = maximal oxygen uptake; ↑ = increase.
Although research has previously investigated the effects of stage duration on blood lactate kinetics and the subsequent identification of lactate threshold intensity,[16] little attention has been given to the influence of stage duration on the peak power output achieved during a maximal incremental intensity step test. Of particular interest to those working with cyclists is the maximal power output MP that is maintained for a fixed period of time (i.e. maximum average power for 30 minutes). For cyclists this information would become synonymous with a runner’s 10km time or a swimmer’s 1500m time. Hopefully, this type of laboratory fitness parameter will become more widely incorporated into future studies characterising elite cyclists, making it possible for coaches to have a better understanding © Adis International Limited. All rights reserved.
3.85 ± 0.30 188 ± 11 10.2 ± 2.5
Peak lactate level (mmol/L)
Power output (W/kg)
63.8 ± 4.2
3.7 ± 0.3
of what standardised cycling performance traits are required for success. 4.1 Age, Height, Mass and Body Composition
In October 2000, the average age of the top 10 UCI ranked women road cyclists was 26.6 ± 2.0 (24 to 30) years.[17] Unfortunately, age is one of the only descriptive characteristics that is readily available on all members of this unique population of cyclists. This average age is similar to that observed in 12 members of the Australian National Road Cycling Team (25.6 ± 4.6, 18 to 34 years; UCI rankings 7th to >200th)[18] and also similar to the average age of US female road cyclists reported by Pfeiffer et al.[14] (28 ± 2.8 years) and Wilber et al.[15] (26 ± 5 years). The average age of the 4 most comSports Med 2001; 31 (7)
Women’s Road Cycling
petitive members of the Australian women road cyclists (25.2 ± 3.1 years) is not noticeably different from the average age of the entire Australian Women’s National Team (25.6 ± 4.6 years), a team that includes some women not ranked in the top 200 in the world. The height of internationally competitive women road cyclists from Australia ranges from 162 to 174cm, which is consistent with previous reports documenting the average height of nationally competitive US women cyclists (i.e. 168 to 171cm).[15] The average body mass (BM) of women who were members of the US and Australian National Women’s Cycling Teams ranged from 59.9 to 61.3kg.[15,18] In 4 of the most internationally competitive Australian Women Road Cyclists BM was between 55.4 to 58.8kg which is comparable to the lighter women cyclists reported in the literature (D.T. Martin, unpublished data). The average BM of internationally competitive Australian women road cyclists is ≈3kg less than the average for the entire Australian national team (57.0 vs 59.9kg). In 2 different studies, the average percentage body fat of competitive US women road cyclists has been reported to be 15.4 ± 4.7% and 15.7 ± 2.0%, respectively, using hydrostatic weighing,[13,14] and 11.9 ± 1.8% using skinfolds.[15] Similarly, the average percentage body fat of the Australian Women’s Road Cycling Team based on skinfold measures was 13.8 ± 4.3%.[18] Internationally competitive Australian women road cyclists were leaner than the average values identified for the Australian Women’s National Team as reflected by a lower percentage body fat (9.3 vs 13.8%) and a lower sum of 7 skinfolds (42.2 vs 58.9mm). In general, the age, height, bodyweight and body composition of women who have been selected to a National Team are fairly similar. In summary, Australian women cyclists who have become internationally competitive are between 21 to 28 years of age, 162 to 174cm, 55.4 to 58.8kg, with 38 to 51mm sum 7 skinfolds and 7 to 12% body fat; values that are similar to those reported in other less successful national team members with the exception of the lower BM and percentage body fat. © Adis International Limited. All rights reserved.
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4.2 Measures of Aerobic Fitness
. Comparing VO2max data between groups of cyclists tested in different laboratories can be difficult. More specifically, testing protocols, expired gas analysis equipment, bicycle ergometers and altitude can all influence measurements of maximal aerobic capacity and all of these variables have been different in those laboratories reporting the aerobic capacity of elite female road cyclists. Despite these . limitations, the average VO2max in top US and Australian women road cyclists is between 57 to 64 . ml/kg/min.[13-15,18-20] In comparison, VO2max ranged from 63 to 70 ml/kg/min or 3.66 to 4.10 L/min in 3 Australian Women Road Cyclists at a time when they were internationally competitive (5th to 138th UCI Ranking). Pfeiffer and colleagues[14] have mea. sured a VO2max of 71 ml/kg/min in a US female road cyclist although the ability of this athlete to compete internationally was not addressed. Australian women road cyclists on the national team generally demonstrate a similar oxygen cost for a given . power output (W) [VO2 in L/min = (0.011 × W) + 0.466].[19] Although the power output–oxygen cost relationship for other competitive women road cyclists has not been previously published, Wilber et al.[15] documented that the change in power output re. quired to increase VO2 by 1L was 91 ± 8 W in US female national team road cyclists. A similar economy was observed in Australian National Team Road Cyclists (91W • L/O2/min).[19] The peak power out. put achieved during the VO2max test averaged 333 ± 21W or 5.5 W/kg in US National Team Cyclists.[15] The average peak power output in Australian National Team Cyclists was 291W. However, the 3 most competitive Australian cyclists within this group (internationally competitive) reached higher power outputs when expressed as a power to bodyweight ratio. Theses values were very similar to those reported for the US cyclists (308W or 5.4 W/kg).[15] The blood lactate level [mean ± standard deviation (SD), Min-Max] 2 minutes following com. pletion of a VO2max test in Australian Women National Team Cyclists was 12.7 ± 1.7, 9.1 to 15.0 mmol/L and these values were not different in the Sports Med 2001; 31 (7)
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3 women on the team who were internationally competitive. These values are slightly higher than the average blood lactate level (10.2 ± 2.5 mmol/L) ob. served following a VO2max test in US women cyclists.[15] This difference could be related to differences in fitness but also to differences in lactate analysers, testing protocols, altitude, time of year the test was conducted and the time post exercise blood was collected. 4.3 Measures of Anaerobic Power and Capacity
Maximum accumulated oxygen deficit (MAOD) is now a commonly used parameter to describe anaerobic capacity. A modified MAOD protocol was performed, and average values for members of the Australian National Women’s Road Cycling Team were established (mean ± SD, Min-Max; 50.6 ± 9.9, 39.6 to 73.1 ml/kg).[19] In the 4 women within this team who were internationally competitive (7th to 89th UCI Ranking) the average MAOD was 13.5% higher (57.4 ± 12.4, 44.7 to 73.1 ml/kg) suggesting that in addition to a greater aerobic capacity, accomplished female road cyclists also have greater anaerobic capacities. With the exception of some preliminary data on Australian Women Cyclists the maximum power output sustainable for a fixed duration in world class cyclists has not been published. Fornasiero et al.[20] performed a repeat sprint test on members of the Australian National Women’s Road Cycling Team. During this test, average power for the first (6 × 15 seconds, 1 : 3), second (6 × 15 seconds, 1 : 2) and third set (6 × 15 seconds, 1 : 1) was 8.6 ± 0.9, 8.2 ± 0.5 and 7.1 ± 0.5 W/kg, respectively. The 3 members of this team that were internationally competitive (5th to 138th UCI ranking) were able to generate higher power outputs (W/kg); increases of 5.2, 4.7 and 1.8%, for sets 1, 2 and 3, respectively. In this group, average power output during a maximal 4-minute effort was 328 ± 13W or 5.4 ± 0.4 W/kg. Internationally competitive women had a similar MP for 4 minutes (MP4min) but because these women were lighter they achieved a 5% higher power output relative to BM. Finally, in Australian National © Adis International Limited. All rights reserved.
Martin et al.
Team Women Cyclists the MP maintained for 30 minutes (MP30min) averaged 259 ± 18W or 4.26 ± 0.43 W/kg. The 4 women who were internationally competitive produced 2.3% higher absolute power (W) and 7.3% higher power relative to body mass (W/kg). These data suggest that internationally competitive women cyclists possess a slightly superior ability to produce an absolute power output for a fixed time period and a greater capacity to produce power output relative to BM. Based on these data it appears that the following time–relative power output relationships exist in internationally competitive female road cyclists: MP6 × 15 sec (1 : 3) = 9.1 W/kg, MP4min = 5.7 W/kg and MP30min = 4.6 W/kg. 5. Demands of Women’s International Road Cycling Competition Road cycling competition for women at the international level incorporates a wide range of formats. The shortest races for women are prologue time trials lasting 7.5 W/kg (11 ± 2 vs 7 ± 2%, p < 0.01), and less time 7.5 W/kg and less time
