The purpose of the study is to ascertain how high-intensity exercise affects heart health. The study's foundation was an investigation of middle-aged persons' main data. These data were gathered using specific questions on high intensity interval training. Studies on the effects of high-intensity interval training (HIIT) on older adults are necessary since exercise is a potent inducer of mitochondrial biogenesis. Examined and summarized using smart PLS software, the study measures the effect of HIIT on mitochondria and various cardio-metabolic health outcomes in older adults, both in good health and with co-occurring conditions. The results produced include descriptive statistics, correlation coefficients, and a smart PLS algorithm model between them. Electronic databases were searched for pertinent studies using variants of keywords related to the cardiac health, the HIIT, mitochondria, cell organelles, and cardio-metabolic health outcomes. This review contains twenty-one papers that satisfied the inclusion criteria. HIIT is an original treatment approach that helps maintain mitochondrial integrity as people age and is a good, safe, and effective substitute for exercise for older persons who are well or sick. Overall, the result found a direct and significant impact of high-intensity training on cardiac health in middle-aged adults