Why athletes are more likely to need pacemakers in old age

Article: http://www.sciencedaily.com/releases/2014/05/140513113254.htm

Article Title:  Why athletes are more likely to need pacemakers in old age

Date Published: May 13, 2014

Summary:

The University of Manchester studied the effects of exercise on the heartbeat by measuring the heartbeat of seasoned athletes in their older age. The normal resting heart rate for an adult is between 60-100 BPM (beats per a minute) while the heartbeats of endurance athletes beat at 30 BPM when they are resting. It used to be believed that this condition was caused by an increased activity in the autonomic nervous system. The pacemaker was controlled by the vagal nerves, part of the autonomic nervous system, which is responsible for lowering the heart rate. But, according to another study by Manchester, there are molecular changes in the pacemaker of rodents when they are exposed to exercise training. A deficiency in an important pacemaker protein , called HCN4 , leads to the abnormally low heart rate. The protein is used in the sinus node(pacemaker), which controls the heart’s rhythm. This whole problem leads to older athletes to need an artificial pacemaker

Connection:

During this term, we learned about how the heartbeat is controlled. The pacemaker sets the rate for contraction by creating electrical impulses which then go to the AV node. We learned that the pacemaker is controlled by the nervous system, more specifically the autonomic part. Also, one of the primary reasons that a rat was used in the other study is because their body organs and body systems are very similar to ours. We even did a whole two day dissection where we saw the similarities. we also learned about the autonomic nervous system. The autonomic nervous system is further divided into the sympathetic division and parasympathetic division . The sympathetic division increases body activity while the parasympathetic division returns the body to it’s normal functions. But more relevantly, the parasympathetic division decreases heart rate by controlling the pacemaker.

Manchester University. "Why athletes are more likely to need pacemakers in old age." ScienceDaily. ScienceDaily, 13 May 2014. <www.sciencedaily.com/releases/2014/05/140513113254.htm>.