system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How does exercising reduce blood pressure and cholesterol to counter stokes/heart attacks.

I was wondering how exercising can reduce things such as blood pressure? Surely when you exercise the heart rate increases to supply blood to organs and muscles that are working overtime, meaning the chances of strokes and heart attacks are higher. So how does this work because wouldn't doctors advise against this to prevent these events from happening?

Edit: 31k Views... Wow guys, thats crazy...
gpt
The heart doesn't work alone to pump blood.

When you exercise, a lot of other systems kick in to help blood get through the body easier and recycle to the heart more efficiently.  Movement of other muscles and one-way valves pushes blood along and veins dilate and contract to direct flow.

Exercise makes those systems more efficient, taking load off the heart.

ELI5: working out starts turning the bloodstream's gravel roads into paved highways so the heart doesn't have to force blood through with so much pressure.