Wearable technology plays an important role in enhancing athletes' performance. These technologies collect various biometric data through devices that are worn or attached to athletes' bodies. This data can be used in many areas such as optimizing training, cognitive skills, preventing injuries and monitoring overall health. These devices are now applying to athletes in the training field or during the competitions as mobile versions and athletes are guided with concrete data. These systems, which provide data to experts in different brands and models, especially neurofeedback and biofeedback systems, have become very useful in understanding and guiding the needs of the athlete. Today, the methods and technologies used to improve athletic performance show great diversity. While in traditional methods there were physical training and competition preparations with experts, nowadays, with technological developments, both physical and mental preparations of athletes are provided with both measurements made with the help of devices and techniques used in training. Devices and psychometric tests are used to better understand, monitor and improve the physical and mental state of athletes.