The promising approach consisting in both a multimodal synchronous study of the human organism functional state and the use of various functional tests is described. These tests include a local heating of surface tissues, forced occlusion of extremity vessels, forced control of respiration rate using a metronome, breath holding, etc. The original hardware and software measuring complex are worked out. It includes an infrared camera, some other original diagnostic instruments and allows for measurement of the physiological parameters as follows: A) breathing rate, b) temperature of the extremities (both a) and b) are determined using focal plane array-based infrared thermography), c) ECG and heart rate, d) pulse wave velocity in the radial artery, e) core temperature, etc. A diagram illustrating the interconnection of synchronously measured responses of the human's cardiovascular and respiratory systems is presented. The developed methodology is original and highly informative. Its complete analogs do not exist today.