In a recent study, researchers found that a specific type of exercise called high-intensity interval training (HIIT) can boost your chances of living longer. HIIT, whether in the form of cycling or weight training, improves age-related decline in muscle mitochondria, the cellular powerhouses that create energy molecules for cells. The researchers also found that HIIT increases the production of proteins in cells that are important for normal body function. Put simply, if you want to improve your health and live longer, consider doing some high-intensity interval training.