Reduced exertion is the main symptom of heart and lung disease. Cardiopulmonary exercise testing (eng. Cardiopulmonary exercise testing) is the gold standard in assessing the degree of exercise intolerance, its cause and symptoms in patients in various clinical conditions. The value of this type of testing lies in the non-invasive and dynamic physiological examination that enables the evaluation of the response of the heart, lungs and circulation to both submaximal and maximal effort, which provides the doctor with relevant information for making decisions in clinical practice. The aim of this work is to gain an insight into the cardiorespiratory, metabolic and physical function of the subjects of the general population of the Split-Dalmatia County in order to assess the status of the subjects. A total of 100 respondents of different ages and genders, body weights and heights participated in the research. Three hypotheses were put forward, the first hypothesis confirms that, based on the analyzed data, the functional ability of the examinee is within the recommended values in relation to the predicted values for age, sex, body height and weight. The second hypothesis is that the functional ability of the respondents in relation to gender is the same in all analyzed age groups. However, the research results show that in the estimated age groups, female subjects have better functional-cardiorespiratory capacity in a greater number of parameters compared to male subjects, and this hypothesis is rejected. The third hypothesis is that the measured values of the O2 pulse (indicator of heart efficiency) are the same for subjects of both sexes. The examination confirmed that the measured values of the O2 pulse in all age groups are higher in female subjects than in male subjects, and the third hypothesis is also rejected. Although the research results showed satisfactory cardiorespiratory fitness parameters for both sexes, of all age groups, it is recommended that everyone, regardless of gender and age, be encouraged to maintain healthy lifestyle habits, especially regular aerobic physical activity, as a key item of all recommendations in maintaining heart health and blood vessels