Sometimes the most bizarre thoughts will pop into my head. Which is probably no surprise to anyone. I realize that most people have weird ideas from time to time; they can't be original thoughts, either. Very few of those left in the world, I suspect.
I once heard or read that the human heart has the capacity for only so many beats. In an average 80 year lifespan it will beat about 3 billion times. Does that mean if you exercise a lot and increase your rate of heartbeats, you'll die sooner? Exercise strengthens the heart, so your resting heartrate will be lower, so the number of heartbeats will even out in the end (I think that's how it would work).
When you live with a diagnosis of MS and one of your symptoms is fatigue, you learn to pace yourself in your day to day activities. Come to think of it, sometimes week to week or month to month. You don't do laundry on the same day that you shop for groceries, for example.
So after Sunday's 21 k bike ride, I was thinking, "What if I have a finite number of long bike rides in me?" Say, 100. Do I get more and more fatigued with each ride until I've reached the finite number and can't ride any more?
Like I said at the beginning, bizarre thought. However, after mulling it over, I think I've rationalized it to this: Each ride will build my physical strength. The exercise is good for both body and brain (increased oxygenation, better circulation of nutrients). My eating habits have improved, so my nutrition is better, and my overall health is improving. And I know that if my overall health is good, my brain is better able to deal with the MS. So if I hit a wall from fatigue, taking a day or 3 or 4 off is not going to set me back. I can get back on the bike and do a couple of shorter rides, then a big one again. After all, marathon runners don't run a marathon every day for training.
I suspect a day will come when a genetic test will determine what number of heartbeats a person is predetermined to have. A full screening at birth will tell us if we are destined to live to 100 or 25. 10 years ago the average lifespan for a person with cystic fibrosis was 18 years. Today it is 35 (last year I met a CF patient who was 40). We will be able to determine and treat conditions in order to extend lifespans; actually, we already do that to a degree. If we are diagnosed with a treatable disease, we take medicines or alter our lifestyle to enable us to not be as affected by our disease. But a day will come when we find out at birth (if not prenatally).
So how many long bike rides do I have in me? Ask me when I'm 80.