**4. Fluid dynamics: manipulating the external environment**

Wearing aerodynamic running kits has been adopted by many athletes and is appreciated as a great way of reducing resistance, hence contributing to better performance times, as one moves through the fluid (water for swimmers, air for runners and cyclists) [24]. This has been taken positively, as even race organisers seem to be quick to judge whether the race times are 'wind assisted' or not [68]. With a long race like a marathon that takes more than 2 hours to complete, air current is a key consideration; thus, the above efforts are needed. While aerodynamic body frames and apparel have been shown to reduce air resistance encountered by runners [69], runners and coaches have also explored running in different positions and formations to take advantage of favourable air currents [24]. This has been augmented by the case of INEOS 159 Challenge, where a formation known as the delta formation, with a group of rotating pacers, was said to have been adopted to remove wind resistance from the main runner, Eliud Kipchoge [24, 70]. Even though the organisers indicated that they extensively tested different formations using manikins, the effects of the formation adopted on the main runner were not specified. Moreover, the choice of the running venue (The Prater Park in Vienna) and a straight and tree-lined course which runs through the heart of the park was said to have been preferred because of its 'optimum

#### *Sports Science and Efforts towards Sub-Two Hour Marathon Performance DOI: http://dx.doi.org/10.5772/intechopen.100005*

conditions' [70], which obviously included relatively calm air. Thus, it was incoherent to think of the running formation as being designed to avoid wind resistance.

We conducted a study to investigate the drafting effects on dummy models of marathon runners using a wind tunnel (San Technologies Co. Ltd) in the Laboratory of Sports Fluid Mechanics, University of Tsukuba, in September 2020. The dummy models were wooden, 0.4 m high and 0.09 m wide. The indoor temperature and humidity were 25.7°C and 68% respectively. The effect of drag force changes in different dummy model positions was evaluated at a wind speed range of 0–56 m/s. The position, distance and angle of the model were changed to test the influence of wind drag force on the main model under different conditions (Group 1–4). A total of 11 tests were conducted in this study. The results showed the following: 1. The wind drag force of the single model was the largest (See **Figure 1** Group 1). 2. When a wooden model is set at 0.3 m and another at 0.7 m in front of the main model at the same time, the wind drag force is very close to when a single model is set at 0.7 m in front of the main model (See **Figure 1** Group 2). 3. When a wooden model is set at 0.35 m in front of the main model, its wind drag force is close to that of two wooden models with a space of 0.045 m in front of the main model (See **Figure 1** Group 3). The influence of the 0° and 45° angles of the wooden model was not significantly different on the wind drag force. 4. Two wooden models were set up side-by-side (no space) in front of the main model. Owing to the influence of the air vortex, some traction force was exerted on the main model (See **Figure 1** Group 4). The wind drag forces were G1 > G2 > G3 > G4. The authors concluded that setting a guard just in front of a runner may be more effective in reducing the wind force than a formation. However, it should be noted that the experiment did not assess a formation similar to that used in the INEOS 159 Challenge.

In another experiment conducted at Kenyatta University, we tested the effects of turbulence induced by moving wooden models in a formation similar to the one used in the INEOS 159 Challenge (Video 1). The models, which were about 2.5 cm wide with a slight oval cross-section (similar to human trunk), were inserted in still water (temperature; 12°C, density; 0.99 g/ml) in a pool and moved at an average speed of 0.41 m/s. Considering the relative size of an adult marathon runner's trunk of about 40 cm in cross-section, the relative speed of the model runners was about 6.56 m/s, which is close to the INEOS 159 Challenge average speed of 6.86 m/s. The effects of the turbulence were observed at the position of the main model by removing it and placing a loose piece of wood in its place. The loose piece of wood was seen pulled along the wood model formation for a distance of 5 meters (Video 1), confirming tail

#### **Figure 1.**

*Wind tunnel experiment results showing wind drag force changes (on the main model) with different positioning of dummy models of marathon runners at different wind speeds.*

suction/vortex forces at the position of the main model. Even though the magnitude of forces generated in water are higher than in the air due to difference in densities, the study concluded that the INEOS 159 Challenge formation generated tail suction/vortex forces which may substantially reduce the energy cost of running for the main runner.

With the preceding evidence that air turbulence can be manipulated to improve performance, the dynamics of applying it in an actual race may not be easy. However, we are likely to see more runners trying to apply the concept in the field with their sponsored pacesetters. If several groups of athletes try this at the same event, jockeying and jostling for spaces is likely to ensue, and this could substantially change endurance running competitions from the way we know it.

### **5. Psychological aspects: power of the mind and motivation**

Mental toughness and preparation often separate the best from the rest, as most top athletes are in outstanding physical condition and are technically exceptional [71, 72]. Mental attributes, such as motivation, confidence, focus, perseverance, resilience, and managing nerves are critical in sports performance, even though they are more often neglected in training. Sports science has shown the importance of incorporating mental training directly into an overall sport training regimen to unlock the power of one's mind through various techniques [71, 72]. It is evident that some top marathon athletes, like Eliud Kipchoge, use some of these sports psychology techniques. This is exemplified by hypnosis and self-belief in the 'no human is limited' slogan, as well as the mental boost gained from encouragement by running teammates [70].
