Cardio – Respiratory Endurance & FITT Principle Study Guide Cardio-respiratory endurance is best described as the ability of the heart and lungs to work together to supply oxygen to your brain. To maximize your cardio-respiratory endurance workout, you should keep your heart rate up for a minimum of 60 minutes per day at a level 4 heart-health. Types of activities could include running, swimming, and dance. By applying the FITT principle you can improve your cardio-respiratory endurance.