I've always been interested in how exercise might help our brain. That's why I became excited when I got a copy of Spark, by John Ratey. It's been around since 2008, yet many of its findings are still not widely know.

The subtitle of the book is "The Revolutionary New Science Of Exercise And The Brain".
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The book is now heavily underlined. I like to underline key passages in books as I read them. The act of underlining helps me remember. 

I am a big fan of the Harvard Health blog. I enjoy reading it - it's science-based and trustworthy.

That's why I was disappointed with the article "Six ways you can help your immune system".

Of the "six ways" five were rather trite. I immediately thought of four better ways than the article suggested, especially in these days of Covid-19.

I didn't know how our energy system worked until I studied for my professional diploma in sports nutrition.
It's helpful to know, as knowing equips you to better match your exercise intensity with your energy capacity.
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We've all had the experience of having to move quickly, and after a short time, our legs feel like lead.

​Perhaps we've had to run to grab one of our children who has made off down the road. Perhaps after our dog who has got off the lead.
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We run strongly for about 10 seconds - feeling pleased with our pace - then find ourselves slowing for about 10 seconds. At this point, we suddenly feel our legs to be heavy and unresponsive. 

Arterial stiffness occurs as a consequence of biological aging and arteriosclerosis. What is often not well appreciated is that exercise can make a significant contribution to reducing arterial stiffness, and thus mitigating the adverse health consequences. 

How does that work?

​Exercising makes the heart work harder and this sends more frequent pulses of blood out into the arterial system. These "pulses" are not just pushed along by the force of the heart, as in a pump pushing water through a hose. The blood is pumped along by the muscles in the arteries contracting and squeezing like squeezing toothpaste.

This exercises the arterial and vascular muscles! The exercise reduces their "stiffness', just like other muscles. 

And in addition, as you exercise your heart it becomes stronger and able to pump out bigger pulses of blood with each stroke. That's why your resting heart rate drops as you get fitter. These bigger pulses make the arterial and vascular muscles work even harder to push the bigger pulses of blood along, and they get even less stiff.