This here is an experimental paper about the mechanical vibrations total resonance (i.e. the discrete frequency where it is found a human body as a whole resonates mostly):
Discussion of human resonant frequency
also found here.
"...found the human whole-body fundamental resonant frequency to be around 5 Hz. However, in recent years, an indirect method has been prosed which appears to increase the resonant frequency to approximately 10 Hz. To explain this discrepancy, experimental work was carried out in NTU. The study shows that the discrepancy lies in the vibration magnitude used in the tests. A definition of human natural frequency in terms of vibration magnitude is proposed."
The analysis of the experimental results of this paper lead to an important conclusion made by the authors that this resonant frequency is amplitude depended in some extend thus it can vary depending the amplitude of the mechanical vibrations.
"...that the higher the vibration magnitude, the lower the detected
human resonant frequency. Therefore, the definition of the human resonant frequency
should refer to the vibration magnitude. This paper suggests that, for practical purpose where the vibration magnitude is higher than 0.1 ms-2 (such as in the study of earthquake and traffic), the human resonant frequency could be assumed in the range of 3 to 7 Hz."
Also another conclusion the authors of this paper making is that most of the vibrations can be dumped by the human depending also by muscle-tension:
"...There is slight difference between various postures. If we refer
to the muscle tension, it can be suspected that tensed postures can damp the vibration more effectively than the relaxed ones"