Many of us wear Fitbits or other fitness trackers. Some of us see a more drastic difference in our resting HR and our max HR when we are participating in the same exercise. Why would this be? What other factors go into this calculation?
The differences between individual’s resting heart rate and maximum heart rate when participating in the same exercise can be due to many factors. A few of those factors can be age, fitness level, stress level, and the intensity at which the workouts are being performed. Despite the differences, a person’s heart rate is an indicator of how hard their heart is working. Aerobic workouts (utilizing oxygen) focus on improving one’s cardiorespiratory system (cardiovascular and respiratory system) so that the body can efficiently utilize oxygen.
During aerobic exercise, checking one’s heart rate against their maximum heart rate (formula = 220 - age) will give the individual an indication of the level of intensity at which they are working out. This intensity level will indicate whether they are in the “fat-burning zone” (approximately 50%-70% of their max heart rate = longer /less intense) or “cardio zone” (approximately 70% - 85% of their max heart rate = shorter / high intensity).
Can you explain the difference between the fat burning zone and cardio zone and why they are both beneficial?
As I mentioned earlier, individuals can be performing the same workout but one is working in the “fat-burning zone” because they may be younger and/or more fit, while another individual is in the “cardio zone” because they are just beginning to get back into shape. Either way, both are working on improving their cardiorespiratory fitness levels and making their heart stronger. What you may see in that situation is that the individual in the "cardio zone” may have to take more breaks or lower their intensity level because working out at that level cannot be sustained. As they strengthen their cardiorespiratory system they begin to work out longer and harder. It is also significant to note that working out at the “fat-burning” and “cardio” levels is both important.
Incorporating both low intensity and high intensity workouts provides variety to a workout which helps to avoid staleness and minimize the risks of overtraining. The heart is a muscle, and just like any muscle in the body the better conditioned it is the better, more efficiently, it will work. The strength of each person’s heart differs. A well-conditioned heart will have a lower resting heart rate because it is more efficient in pushing the blood through the body with each beat than an unconditioned heart.
Heart rate is an important indicator of fitness and the health of our heart. Just like other muscles in the body, the heart is best served by being exercised through aerobic workouts.
Dr. Lester Sombito is a Sports Management specialist and an assistant professor in the Exercise & Sport Science Department at UMHB where he teaches health & fitness classes. He is the first Temple Fit4Mom Professional of the Quarter in 2017.