This paper investigates the use of 3D information in the context of sports training. More specifically, a weightlifting athlete attempt is monitored, helping any coach to train athletes as she/he prefers. Our aim is to detect, collect and extract every useful data which give insight about the body technique during the weightlifting attempt and therefore make all the necessary calculations. A Kinect sensor is used for tracking the weightlifter and collecting depth data during the attempt. Afterwards, data are processed, so that useful information is extracted. In addition, after any attempt, data can be saved and loaded at any time. 2D and 3D graphs are used to illustrate the relevant information. Finally, two attempts can be loaded in parallel for the comparison between two different athletes or between a new and an old registered attempt, giving the ability for matching and correcting different techniques.