It may seem counter intuitive, but when you are losing weight, strength training, not cardio training should be your number one exercise priority. When you place your body in a caloric deficit, it is normal for your body to burn a combination of stored body fat and muscle to meet its energy needs, but you can prevent this loss of muscle mass through strength training. The human body has been conditioned to adapt to the stresses place on it by its environment by making it more resilient to the stress the next time it’s encountered. If your body is required to lift heavy objects using all the muscles of the body, on a frequent basis, it will preserve muscle and burn fat exclusively when in a caloric deficit, assuming you are consuming sufficient quantities of protein. That is why strength training should be your number one exercise priority.