Cardio is great for increasing your heart rate, moving your body and overall health. However it does not reshape your body. Strength (resistance) training and proper nutrition are the two main factors in transforming your physique. Strength training will add lean muscle to the body which will decrease body fat and increase metabolism. By increasing the metabolism you will burn more calories at rest. Cardio burns calories in the moment, strength training burns calories all day! Pair that with a good nutritous diet and your body will slowly and safely transform into a lean mean fighting machine.