Don’t worry this is not the target for your normal resting heart beat, if its this low you certainly have problems. A stress test is when we put our heart under some sort of exercise stress and then draw conclusions about how the heart is shaping up to the exercise. There are various sophisticated measurements that can be applied to evaluating your heart health during a stress test but one simple one you can do yourself is to test your recovery rate.
Take yourself for a run around the block in the absence of a tread mill, and run so that you are at 75% of max, that’s so that you can hold a short conversation whilst running. Your heart beat needs to be raised by at least 25 beats per minute more than this would probably be better. You check your heart rate at the end of the run and then again 1 minute after resting. Doctors who administer this test are looking for a reduction of 25 beats per minute at the end of that first minute. So if your heart rate has been raised to say 100 per minute then they are looking for it to come back to 75 beats by the end of one minutes rest. It’s a simple test you can try yourself even without a heart rate monitor. Take a 10 second count on rest and multiply this by 6 to get your beats per minute and then rest for 1 minute and repeat.
I did two tests just to make sure I was getting reasonable readings. The first run elevated my heart to 120 beats per minute based on a 10 second count. After 1 minutes rest this had dropped by 42 beats to 78 beats per minute. The second test was pretty much the same coming in at 126 down to 84 beats.