The kart is the most pure racing vehicle ever created. It has the essential components found in all racing machinery. A tuned chassis, strong brakes and a motor designed to be revved to within an inch of its life.
Nothing will train your body to have a more immersive experience with a race track than a kart. Nothing at all. You’re sitting as one with the machine, as the entire chassis is flexing around you. You feel every camber change and every change in grip surface interacting with your body immediately.
A crucial thing about motorsport, both at a club and at a professional level is the level of preparation that it takes from both the driver and the equipment to be successful. Leaving a ten-cent bolt loose, or forgetting a tool, can be just as tragic for a race weekend as a driver not being properly ready physically.
This time-lapse video from Carlin Motorsport just gives an example of how much work it takes them to get ready for a race weekend.