A team of scientists in Japan says it has developed a relatively simple method to visualize the movements of a person's muscles and joints.

The technology uses artificial intelligence to produce three-dimensional images.

Conventional motion-capture technology is used for analyzing athletes' movements to improve their performance, among other purposes. But the method requires the use of sensors and other special devices, as well as data analyses by experts.

The study group at the University of Tokyo says its new system can create 3D images more simply by using four cameras remotely connected to an AI-equipped computer network.

The group says the technology analyzes subjects' images taken by the cameras, assesses positions of their joints, and puts the data into models to construct 3D images of their skeletal frames and joint movements.

It also displays muscles in different colors to indicate their amount of physical activity.

Once the cameras are correctly set up, the system does not require special equipment or experts' assistance to record subjects' movements.

University of Tokyo Senior Researcher Nakamura Yoshihiko is a member of the research group. He said he hopes the new system will go beyond the conventional applications and be used for such purposes as supporting rehabilitation and training amateur athletes.