This paper presents a novel solution for noninvasive real-time heart rate monitoring by the Microsoft device Kinect™ version 2.0. In this paper, it is firstly evaluated the state of the art concerning the solutions for non-invasive detection of vital signs and secondly it is presented the implementation and the tests of a novel methodology for evaluating the heart rhythm by a non-invasive monitoring system based on Kinect™ 2.0 sensor, acting at medium/long distance. The standard method to monitor physiological information exploits photoplethysmographic images, in fact, changes in blood volume can be determined from the spectra of light reflected from (or transmitted through) body tissues. Using a mathematical processing developed and written in Python code, the study shows how it is possible to real-time estimate the heart rate of people in front of the sensor at distance 2.5 m. In order to prove the correctness of the method proposed, two different tests are implemented and 30 different subjects are involved in the test phase. The first test aims to detect the real-time heart rate while the subject is in standing position for 1 minute. The second test gathers heart rate data while subject is performing three different series of rehabilitation exercises. During the tests, each subject wears a pulse oximeter for comparing the values acquired through the Kinect™.