One theory I've heard mentioned to me is the concept that we all have a limited number of heart beats after which we die. The people espousing this thoery to me claim I am very quickly using up all my available heart beats and will come to a grinding halt well before my time. I thought about this for a while and decided I should look into it a bit more just to reassure myself that I'm not heading for an early grave. The results are very interesting
If we compare three people - me, someone who is moderately fit and trains for 3 hours per week and someone who does no exercise at all.
First of all lets consider the resting heart rate which is basically your heart rate when you are asleep. Mine is around 32( I've heard Lance Armstrongs is 28), an average fit male of 40 years of age is 60 and unfit would be 80.
Looking at exercise - I exercise an average of 12 hours per week, an average person 3 hours and obviuosly 0 for the unfit person. For the sake of comparison I'm assuming that for most of the day our heart rates are fairly constant and around 20 beats higher than resting and I'm assuming heart rate is another 20 beats higher than that when we walk to the tube, argue with our boss, get stressed driving in the car etc etc. I'm also assuming an average heart rate of 145 during exercise.
Here's the figures for a week.
Total hours = 168
Sleeping assuming 7 hours sleep = 7 x 7 = 49 hours
Exercise - me 12, average 3, unfit 0.
Time at 40 beats above resting - 2 hours per day = 14
Time at 20 beats above resting is whatever is left over.
Here is the total hear beats per week for each of the categorie
time at 20 above resting ......273000...428400....567000
time at 40 above resting.......67200....84000.....92400
Total heart beats per week...556080...685500....835800
Result is my heart beats 129,400 less times per week than an averagely fit person and 279,720 less times than someone unfit.
This means my heart takes 8.6 days to beat the same number of times as someone of moderate fitness beats in a week and 10.5 days to beat the same as someone who is unfit.
If we assume a lifespan of 75 for an unfit male, this equates to 3,259,620,000 heart beats. The average fit person will take 91 years to use this number of heart beats up and I will live to the grand old age of 112! So if anybody is around in the year 2081 come and look me up to see if my thoery is correct!
Obviously I have made some rather big assumptions for these figures but I think it illustrates the point that even if there is some truth to the theory of a finite number of heart beats then the fitter you are the better your chances of living longer!