What makes an athletics track fast?

What makes an athletics track fast? This question is particularly relevant as the Paris Olympics approach, with the new track at the Stade de France set to be a highlight. The track, which is a striking purple color, is designed to be not only visually appealing but also incredibly fast. Maurizio Stroppiana, the head of the company that constructed the track, describes its color as 'audacious' and believes it will help people instantly recognize the Paris Games. The installation of the track took ten weeks, following the conclusion of the Rugby World Cup last October. Mr. Stroppiana expresses his satisfaction, stating, 'Finally, when we see it installed, it's absolutely beautiful. ' His company, Mondo Group, has been responsible for creating Olympic tracks since 1976, and they claim that this new track is the fastest they have ever produced, boasting a speed that is 2% faster than the track used in Tokyo during the 2020 Olympics. Beneath the vibrant purple surface lies a sophisticated rubber track composed of two layers. The lower layer features a honeycomb structure that absorbs the impact of a runner's foot striking the ground, subsequently releasing energy to propel the runner forward as they take off again. The evolution of athletics tracks has been remarkable over the years. For instance, Sir Roger Bannister made history in 1954 by becoming the first person to run a mile in under four minutes, achieving this feat on a cinder track, which was considered the best surface available at the time. Cinders, which are small pieces of volcanic rock, were mixed with clay and other materials to create a durable running surface. While cinder tracks were an improvement over dirt or grass, they had a significant drawback: they would leave runners covered in dirt when it rained. Maria McCambridge, who competed in the 5,000 meters at the 2004 Athens Olympics, fondly recalls the messy experience, saying, 'It was always fun to see yourself at the end of a session. ' The Olympics continued to use cinder tracks until 1968, when they transitioned to polyurethane tracks, known as 'Tartan' tracks, which were more resilient in wet conditions. This change was prompted by the frequent cancellations of athletic events due to rain on cinder tracks. Today, the materials used in athletics tracks have advanced significantly. Shaun Goudie, who leads a sports surface company, explains that modern polymers can be tailored to enhance specific properties, such as resistance to spikes and ultraviolet light. The 1968 Mexico City Games marked the first Olympics to utilize a polyurethane track, while the 1976 Montreal Olympics introduced a rubber track made by Mondo. Maria McCambridge appreciated the Mondo track at the Athens Olympics, noting that it felt faster than the older Tartan tracks. However, she also mentioned that the hardness of the surface could lead to tight muscles for some runners. 'Participants in the 10,000 meters would often be seen wearing racing flats over spikes for that reason,' she recalls. A well-designed track must possess both hard and soft characteristics. João Bomfim, a polymer chemist, emphasizes that a harder surface allows for faster running. 'You can run quicker on concrete or asphalt than sand on the beach,' he explains. However, the impact of running can exert a force three times a person's body weight on the track, necessitating a design that absorbs this force to prevent injuries. By utilizing two layers of rubber and selecting different materials for each layer, track designers can create surfaces that enhance forward motion while minimizing the risk of injury. Tadhg Sullivan, from an athletics club in Ireland, highlights the differences between polyurethane and rubber tracks. Polyurethane tracks are mixed on-site, while rubber tracks are manufactured in sections at a factory and assembled on location, making them easier to install in regions with heavy rainfall, such as Ireland. Oxford University is also in the process of installing a new track, which will be dark blue, reflecting the university's colors. Anika Schwarze-Chintapatla, a steeplechase runner studying medicine, is eagerly anticipating the new track, as the previous surfaces had caused her stress fractures. 'I'm really excited about the new track, and injury being less of a worry,' she shares. The development of athletics tracks has increasingly focused on environmental sustainability. The Paris track is composed of 50% recycled materials, and other companies are producing eco-friendly tracks using renewable resources. As a result, whether they are red or purple, the future of athletics tracks is likely to be greener and more sustainable.