Defining Heart Rate 
The rate at which the heart beats every minute is measured in terms of Beats per Minute (bpm). Also defined as the number of pulses of the heart in a minute or the number of times the heart expands and contracts in a minute, the range of the normal adult heart rate is around 70 bpm in males 75 bpm in females, but this may vary between people. In a child, it ranges from 80-120 bpm. While at rest, it ranges 24 to 44 beats per minute. Analyzing the heart rate of an individual can give a quick overview of his general health condition.

Low heart rate:

Low heart rate means that the heart is beating too slowly usually less than 60 beats per minute. It is important to understand that for some people with healthy hearts, a rate below 60 beats per minute may be normal. After all, our heart rates may dip below normal range when we sleep, and some athletes experience heart rates below 60 beats per minute when they rest. The two most common causes of bradycardia are diseases of the senatorial node sick sinus syndrome, which is the heart's natural pacesetter or other problems with the heart's electrical conduction system heart block. These diseases can cause the heart to beat too slowly all the time or occasionally. In either case, the heart may not pump enough blood to meet the body's needs. As the heart rate declines, there is not sufficient blood flow to the brain, causing feelings of light-headedness, and sometimes, fainting. Every normal heart has a normal rhythm. That rhythm varies from person to person. In most healthy people, the heart at rest beats about 60 to 100 times per minute. A small bunch of heart cells called the sinoatrial node keeps time. Many athletes especially runners have low resting heart rates. As long as the EKG shows a normal sinus bradycardia, and as long as the heart rate rises appropriately with exercise, there is usually no problem. A low heart rate can sometimes cause faintness or lightheadedness, in addition to fatigue, but this does not appear to be the case with you. An under active thyroid can cause a low heart rate. Sometimes electrolyte imbalances can cause a low heart rate and this is of particular concern if someone is on a very restrictive type of diet.

Symptoms of low heart rate are: 1. Fatigue, weakness 2. Dizziness 3. Lightheadedness 4. Fainting  5. Shortness of breath.

What is Maximum Heart Rate?

A heart can beat the fastest when an individual is involved in any activity. How hard and fast can a heart beat per minute, without resulting in a fibrillation can be measured in terms of ‘Maximum Heart Rate’ (MHR)? The maximum allowable heart rate can be estimated by subtracting an individual’s age from 220. Rather than measuring the peak of the heart rate during any activity, it is easier to calculate the Maximum Heart Rate with the formula – 220 deducted by age in years. The MHR varies in the human beings with the age, levels of fitness. More the age of a person, lower is the Maximum Heart Rate count.

More about Maximum Heart Rate – A healthy heart would not be damaged when the heart rate exceeds the given MHR count. Or else, many athletes who train their hearts to the extremes of the MHR would have their hearts damaged. A healthy heart’s muscles would not be burnt or damaged even if the heart rate exceeds 90% of the MHR. A true MHR is the highest heart rate attained at the highest level of activity, so by its very definition, MHR is impossible to be exceeded. Regular training lowers the MHR as well as the resting heart rate. This happens because the muscles which are exercised become more strong and well-organized, and pump more blood at each beat.

Some facts and figures about Maximum Heart Rate –  

With age, MHR drops down from around 220 bpm in children to around 160 bpm at the age of 60. which would be a drop of 1 bpm per year. There is no evidence showing that the training affects the decline. The best way of calculating the MHR is a stress test than the age-related formula, since the MHR still varies between individuals of the same age. But the resting heart rate is affected by endurance training to a great extent.

Ideal heart rate:

Any of the exercise that increases your heart rate will burn calories and increase your metabolism. But, if you really want to know then let us do the work for you. We should exercise properly for the heart rate. Nowadays in the gym also they have equipments for heart works. Many athletes and performance-related occupations such as paramedics, fire fighters and police officers often challenge their aerobic levels to the max by participating in a battery of tests which assess their oxygen capacity and measure their maximum heart rate response. These men and women are tested under medically supervised settings, so you could not repeat these tests at home or at your local fitness center. There are different types of training zones. The level of fitness, maximum heart rate is very closely related to age regardless of gender, fitness level or resting heart rate.  Whether we are talking about a coach potato or endurance athlete, maximum heart rate will decline just the same for either person, which is why the formula 220-age is universally accepted as the standard to calculate age-predicted maximum heart rate. 

What should your heart rate be during exercises? 

The number of formulas for determining your ideal heart rate while you exercise. And that rate can vary depending on your level of fitness and your fitness goals. Obviously if you training for a marathon your heart level would exceed a person trying to get back into shape and lose weight. According to the American Medical Association, your maximum heart rate is approximately 220 minus your age. The target heart rate should generally be between 50 and 75 percent of your maximum heart rate. This is your ideal heart rate during aerobic exercises like brisk walking or jogging. They have a chart that breaks down the rate for different ages. You should maintain yourself by working in gyms and should have proper diet should be there for the heart to be strong and avoid alcohol and cigarettes. And elder people should be fit and do walking daily to keep the heart strong. If your resting heart rate begins to increase and you notice a decrease in performance, you may be over training.