The division of athletes into male and female categories for competition is a widely accepted practice and is ordinarily straightforward, requiring no intervention from authorities. However, for reasons ranging from deliberate cheating to complex medical conditions resulting in ambiguous development of sex organs, the controversy of sex verification in athletic events has existed for 70 years. Testing procedures, initially implemented to prevent cheating by men masquerading as women, have produced humiliating outcomes for women athletes who were often for the first time confronted with the possibility that they have one of the disorders of sex development. Sporting authorities have and continue to formulate position stands for the management of such cases. An important missing component in this debate is the sound scientific evidence to determine (a) whether a performance advantage actually exists and (b) how large it might be. The division of competition into separate categories and the large difference in sporting performance between male and female necessitate that sport-governing bodies define the boundaries between the sexes in a just and fair manner for all participating athletes. This review will therefore provide the historical context of the debate and aim to discuss relevant physiological and performance aspects of the sex verification process.
Ross Tucker and Malcolm Collins
Ross Tucker and Jordan Santos-Concejero
The aim of the current study was to analyze men’s and women’s world records across the full range of running disciplines to contextualize the recent debate about the possibility of a sub-2-h marathon. The average male–female gap is currently 11.2% ± 1.0% for all running events. However, reducing the marathon time to below 2 h would produce a performance 12.9% (+1.7 SD) faster than the women’s marathon record. This gap would be greater than all current world-record differences and would also require a reversal of medium- and long-term historical trends in the men’s and women’s record differences. We therefore conclude that based on historical trends and known differences between men’s and women’s performances, the current women’s world record is not yet the equivalent of a sub-2-h marathon and, therefore, that an imminent sub-2-h marathon is implausible.
Ross Tucker, Vincent O. Onywera, and Jordan Santos-Concejero
To investigate the ethnicity of Kenya’s most successful international runners, tracking their evolution over the period of their international emergence and current dominance.
The authors analyzed male track distance events from 800m upwards from all the major global athletics championships from 1964 to 2013, and the annual Top-25 world marathon performances since 1990.
The percentage of top-25 marathon performances and medals won by Kenyan and Kalenjin runners have increased over time with Nandi subtribe outperforming the rest of the world outside Africa (r > .70, large effect). However, Europe, North America, Oceania, Asia, and South America decreased over time in top marathon performances and track medals won (r > .70, large effect). The tribe and subtribe distribution was different in the marathon than in the track: Maasais were more likely to feature in medals won in shorter track events than in the top 25 of the world marathon rankings (risk ratio [RR] = 9.67, very large effect). This was also the case for Marakwets (RR = 6.44, very large effect) and Pokots (RR = 4.83, large effect). On the other hand, Keiyos, Kikuyus, Kipsigis, Sabaots, and Tugens were more likely to succeed in the marathon than in shorter track events (RR > 2.0, moderate effect).
These data emphasize that the previously documented emergence of African distance runners is primarily a Kenyan phenomenon, driven by the Kalenjin tribe and in particular the Nandi subtribe. This supports the complex interaction between genotype, phenotype, and socioeconomic factors driving the remarkable dominance of Kenyan distance runners.
Ross Tucker, Michael I. Lambert, and Timothy D. Noakes
To analyze pacing strategies employed during men's world-record performances for 800-m, 5000-m, and 10,000-m races.
In the 800-m event, lap times were analyzed for 26 world-record performances from 1912 to 1997. In the 5000-m and 10,000-m events, times for each kilometer were analyzed for 32 (1922 to 2004) and 34 (1921 to 2004) world records.
The second lap in the 800-m event was significantly slower than the first lap (52.0 ± 1.7 vs 54.4 ± 4.9 seconds, P < .00005). In only 2 world records was the second lap faster than the first lap. In the 5000-m and 10,000-m events, the first and final kilometers were significantly faster than the middle kilometer intervals, resulting in an overall even pace with an end spurt at the end.
The optimal pacing strategy during world-record performances differs for the 800-m event compared with the 5000-m and 10,000-m events. In the 800-m event, greater running speeds are achieved in the first lap, and the ability to increase running speed on the second lap is limited. In the 5000-m and 10,000-m events, an end spurt occurs because of the maintenance of a reserve during the middle part of the race. In all events, pacing strategy is regulated in a complex system that balances the demand for optimal performance with the requirement to defend homeostasis during exercise.
Nicholas Tam, Ross Tucker, Jordan Santos-Concejero, Danielle Prins, and Robert P. Lamberts
Context: It is debated whether running biomechanics make good predictors of running economy, with little known about the neuromuscular and joint-stiffness contributions to economical running gait. Purpose: To understand the relationship between certain neuromuscular and spatiotemporal biomechanical factors associated with running economy. Methods: Thirty trained runners performed a 6-min constant-speed running set at 3.3 m·s−1, where oxygen consumption was assessed. Overground running trials were also performed at 3.3 m·s−1 to assess kinematics, kinetics, and muscle activity. Spatiotemporal gait variables, joint stiffness, preactivation, and stance-phase muscle activity (gluteus medius, rectus femoris, biceps femoris, peroneus longus, tibialis anterior, and gastrocnemius lateralis and medius) were variables of specific interest and thus determined. In addition, preactivation and ground contact of agonist–antagonist coactivation were calculated. Results: More economical runners presented with short ground-contact times (r = .639, P < .001) and greater stride frequencies (r = −.630, P < .001). Lower ankle and greater knee stiffness were associated with lower oxygen consumption (r = .527, P = .007 and r = .384, P = .043, respectively). Only lateral gastrocnemius–tibialis anterior coactivation during stance was associated with lower oxygen cost of transport (r = .672, P < .0001). Conclusions: Greater muscle preactivation and biarticular muscle activity during stance were associated with more economical runners. Consequently, trained runners who exhibit greater neuromuscular activation prior to and during ground contact, in turn optimizing spatiotemporal variables and joint stiffness, will be the most economical runners.
Jordan Santos-Concejero, Jesús Oliván, José L. Maté-Muñoz, Carlos Muniesa, Marta Montil, Ross Tucker, and Alejandro Lucia
This study aimed to determine whether biomechanical characteristics such as ground-contact time, swing time, and stride length and frequency contribute to the exceptional running economy of East African runners.
Seventeen elite long-distance runners (9 Eritrean, 8 European) performed an incremental maximal running test and 3 submaximal running bouts at 17, 19, and 21 km/h. During the tests, gas-exchange parameters were measured to determine maximal oxygen uptake (VO2max) and running economy (RE). In addition, ground-contact time, swing time, stride length, and stride frequency were measured.
The European runners had higher VO2max values than the Eritrean runners (77.2 ± 5.2 vs 73.5 ± 6.0 mL · kg−1 · min−1, P = .011, effect sizes [ES] = 0.65), although Eritrean runners were more economical at 19 km/h (191.4 ± 10.4 vs 205.9 ± 13.3 mL · kg−1 · min−1, P = .026, ES = 1.21). There were no differences between groups for ground-contact time, swing time, stride length, or stride frequency at any speed. Swing time was associated with running economy at 21 km/h in the Eritrean runners (r = .71, P = .033), but no other significant association was found between RE and biomechanical variables. Finally, best 10-km performance was significantly correlated with RE (r = –.57; P = .013).
Eritrean runners have superior RE compared with elite European runners. This appears to offset their inferior VO2max. However, the current data suggest that their better RE does not have a biomechanical basis. Other factors, not measured in the current study, may contribute to this RE advantage.
Deryn Bath, Louise A. Turner, Andrew N. Bosch, Ross Tucker, Estelle V. Lambert, Kevin G. Thompson, and Alan St. Clair Gibson
The aim of this study was to examine performance, pacing strategy and perception of effort during a 5 km time trial while running with or without the presence of another athlete.
Eleven nonelite male athletes participated in five 5 km time trials: two self-paced, maximal effort trials performed at the start and end of the study, and three trials performed in the presence of a second runner. In the three trials, the second runner ran either in front of the subject, behind the subject, or next to the subject. Performance times, heart rate, RPE, and a subjective assessment of the effect of the second runner on the athlete’s performance were recorded during each of the trials.
There was no significant difference in performance times, heart rate or RPE between any of the five trials. Running speed declined from the 1st to the 4th kilometer and then increased for the last kilometer in all five trials. Following the completion of all trials, 9 of the 11 subjects perceived it to be easier to complete the 5 km time trial with another runner in comparison with running alone.
While the athletes perceived their performance to be improved by the presence of another runner, their pacing strategy, running speed, heart rate and RPE were not significantly altered. These findings indicate that an athlete’s subconscious pacing strategy is robust and is not altered by the presence of another runner.