In the first episode of a three-part series, BBC tech journalist and huge Olympic fan Paul Carter goes behind the scenes to see how technology underpins so much of the Olympics and Paralympics - from the events themselves to the way 'digital twins' of most of the key venues have been created in the virtual world. These simulations allow organisers, broadcasters and athletes to see precisely how these arenas will operate before they are even built, reducing the number of site visits needed to Paris.With access to major venues and top training facilities, TechXplore gets a sneak peek at the tools developed to streamline the Olympic and Paralympic experience for fans and athletes, including the private 5G networks installed to help capture the opening ceremony and sailing events.With exclusive access to athletes in the build-up to the games, Paul also visits Norway and the training camp of reigning triathlon champion Kristian Blummenfelt to see how heat tracking sensors are helping him push his body to the limit. And we find out how US Olympic football captain Lindsey Horan is creating a digital twin of her own muscles - using MRI scans and AI to visualise the micro-differences in her body to allow a more purpose-built training regime.