Cardiovascular exercise is great for fat loss and improving overall health. A strong heart and healthy lungs are essential for a healthy body. The intensity of the cardiovascular exercise directly impacts the duration of the activity. The number of calories burned, the heart rate, and the muscular involvement are all affected by the intensity of the exercise.
High Intensity Cardio
High intensity cardio exercise increases the number of calories burned per minute, but generally lasts a shorter amount of time than low intensity exercise. It also raises the heart rate quicker and to higher levels. It increases the respiratory rates quicker, as well. The muscles are generally taxed more during high intensity work and may even result in some muscle growth and strengthening.
Low Intensity Cardio
Low intensity cardio is usually performed for longer periods of time, often resulting in the same number of calories burned because of the longer span of time. The heart rate generally increases at a slower rate and may top out at a lower level. The respiratory rate may increase slower, but often reaches the same level over time. The muscles are usually not worked as intensely, which is why the activity can be done for a longer period of time. The muscle may develop endurance through the activity, but it usually does not result in size or strength gains.
The intensity of cardio exercises is relative to the experience and fitness level of the exerciser. For some people jogging is a high intensity activity, while for others it may be low intensity. Some people can swim very easily while others struggle with it. The intensity of the exercise is best measured by the heart rate and exertion level. If it requires a lot of energy to perform the exercise for a short period of time and the heart rate rises quickly it is probably a high intensity exercise. If you can talk comfortably and perform the exercise for a longer period of time then it probably is a lower intensity choice.
Okay, so know we know the difference between high and low intensity, so what are the specific benefits of each? Low intensity exercise is good for beginners and those with specific health issues (such as cardiac or respiratory concerns.) It can be done over a longer period of time, increasing the amount of fat burned over that time. In general, although not the case in all exercises, lower intensity cardio usually is also lower impact on the joints, as well. The steady increase and leveling off of the heart rate is better for improving the health of the heart and blood vessels.
High intensity cardio burns more calories in a shorter period of time. It also works the muscles more intensely so there is some muscle building potential. It requires the heart to pump stronger, thereby strengthening the muscles of the heart (although it may also thicken the walls of the heart.) This is usually not a good idea for beginners because of the muscle soreness and the taxing of the cardiovascular system.
High Intensity or Low Intensity Cardio?
High intensity or low intensity is often the question for the person looking to lose fat. The best answer is to start out with low intensity exercise to get your cardiovascular system accustomed to the increased work load and then slowly add in some high intensity work once in a while to spice things up and boost the overall metabolism. What started out high intensity may quickly become low intensity.