Water-aerobics has been purposed as an attractive alternative to land-based exercise for achieving improved health and fitness in populations with orthopaedic or musculoskeletal limitations, excess adiposity or other medical recommendations. This is reflected in the growing interest of scientific community on this matter, increasing the publications in the last few years. Despite this increase of interest by participants and sports community, it seems not clear what might be the benefits that water-aerobics lessons provide to adult population. Some studies evidenced improvements in physical fitness, aerobic capacity, strength, flexibility, but some pointed the opposite conclusions (Barbosa et al., 2009; Benelli et al., 2004). In this sense, it is understood that there is no uniformity and clarity of results maybe because of the testing and procedures used, because there is likely to exist some differences between those evidences reported by studies and real practice. So, regarding the effects of aquatic exercitation in health status and physical fitness, the main gaps that could be highlighted in scientific research are the lack of longitudinal studies on several other health variables (i.e. blood pressure, triglycerides, cholesterol) in usual practitioners and the gap between the laboratorial context and the real-venue context (Bergamin et al., 2012; Delevatti et al., 2015; Volaklis et al., 2007).The main purpose of the present study is to verify the effects of a 12-week water aerobics program on health indicators (lipid profile and blood pressure) and physical fitness (strength, cardiorespiratory fitness, and body composition) in adults and older adults. This project would allow to develop a master thesis and the results should also be published in a scientific journal to knowledge the scientific community and water-related professionals.