In fact, HIIT is ideal for burning calories and boosting your level of physical training.
HIIT exercises are designed to bring your body to a maximum stress level in a short time so that the body can use this intensity to burn even more calories and at the same time cope with physical difficulties. The key of this process is not the level of the exercise intensity, but the recovery process. If you try to maintain such maximum intensity throughout the whole workout, your body will burn out because of the extreme challenge. Moreover, at this time, parts of the body may damage, or the process of calorie burning slow down because the high production of the stress hormone can in return cause the inflammatory process in the body.
Therefore, during the HIIT workouts, we should force our body to reach 100% of heart rate and then, during the low intensity, it should reach the maximum of 60-70%. These intense intervals last from an average of 20 seconds to 2 minutes, depending on your physical readiness. Calculating your highest heart rate is easy: 220 minus your actual age and the result will be your heart rate.