Effects of training on heart rate

The number of times your heart contracts during each minute is your heart rate. Actually, both the right and left sides of the heart (the ventricles) contract simultaneously, but these two contractions count as one beat. The left ventricle of the heart fills with blood from the lungs during its rest period between beats. When the heart beats, it pumps that blood, out to the muscles. The right ventricle fills with blood returning from the muscles during the rest period and then pushes that blood out to the lungs.

When you start your swimming training (or any other aerobic type of exercise e.g. cycling, running, dancing) your heart rate speeds up because your heart must pump faster to deliver the additional blood and oxygen that your body needs to work out. This is a healthy response. The Montana State University states that to get the best benefits from aerobic exercise you want to work out hard enough that you reach your target heart rate. Your target heart rate is determined by your age, current level of fitness and if you are on any medications which interfere with your heart rate. If you are new to exercise or deconditioned it will not take much to raise your heart rate up. Aerobic exercise conditions your heart and makes the heart muscle stronger. If you participate in aerobic activity on a regular basis you will have to work out longer or harder in order to get to the same target heart rate. This signals that your heart muscle is getting stronger and can handle a heavier workload.

Another indicator of how well your heart is working is how long it takes your heart rate to return to a pre-exercise level, after you stop working out. A strong heart can quickly recover from your workout. If you are out of shape then it will take longer for you to be able to catch your breath and slow your heart rate down. This can be tested with one of the various three-minute-step tests. This involves taking your heart rate before, during and then at one minute intervals after exercise. The Tufts Longitudinal Health study claims that a fit person will have a lower heart rate within at least three minutes after finishing the test if not sooner. If it takes longer for you to recover, then you are considered deconditioned.

Finally, endurance training affects your resting heart rate. Resting heart rates are in the neighborhood of 60 to 80 bpm for most untrained persons and between 30 to 50 bpm for the trained athletes. It’s easy to understand that training reduces the resting heart rate; that’s because the cardiac muscles of the heart become larger and stronger from training and they can push more blood out with each beat. Consequently, the heart requires fewer beats to supply the usual quantity of blood an athlete needs at rest.  

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