If you sit too much, you don't get enough physical activity. Without physical activity, your muscles and bones weaken, your heart weakens, your circulation and blood pressure get affected, your metabolism activity gets reduced in multiple ways, you burn less energy thus you're more prone to getting fat, you lose flexibility / mobility in your joints... So you get into this whole web of interconnected causes and effects that negatively affect your health.

Physical activity, on the other hand, helps maintain or develop bone and muscle strength, you train your cardiovascular system, you activate processes in your metabolism that help keep your body running efficiently, hormones get produced.

The comparison has a lot to do with the effects on the cardiovascular system. Circulation requires muscle movement to help return blood to the heart (why long periods of sitting puts you at risk for clots). Physical activity also exercises heart muscle, making it stronger for its functions.

I am very confused about the <. Between 50 and 60 minutes?

When you walk your calf muscles help to circulate your blood. Without that movement it increase the risk of blood clots, which can lead to stroke and heart attack.

Yeah, same here. Prolonged durations shorter than one hour are bad?

circulation....

VENTILATION (are you breathing aptly?)

hmmmm

, depending on your points of squashed fleshy parts & prominences, veins suffering and VERICOSE VEIN RISKS ARE UPPED!!!!!OH NOOOOOO.

thanks for letting me contribute!-c

I think they just used the wrong ><><><><><><

Can a Stallone sit all day? No hell have a heart attack but a Mike Myers can. How fat are you to worry about such an issue?

Consider what your body is adapted to over millions of years of evolutionary history. Go back in time ten thousand years, a blip in that history but to a lifestyle that is reflective of the other millions of years.

Your ancestors spent lots of time outside, did physical activity all day, ate whole unprocessed food, didn’t have screens and cars and light switches, and didn’t sit down for huge periods of time.

Science is finding that as we deviate from those things we develop illness, our bodies don’t handle it well. Your body needs to move a lot to work properly, sitting or lying down all day is not what it is adapted to and its systems break down. Blood doesn’t flow properly, raising clot risk. Bones soften, muscles atrophy, postural issues develop, important hormones get out of whack, risks of metabolic syndrome increase, heck even sexual function deteriorates.

Thing is, people are adapted to an environment where we HAD to be active and work a lot, and we have an instinct to minimize energy expenditure within the framework to conserve calories. If the natural situation where a lot of work is inevitable is gone, turns out we can often be pretty lazy and not move much at all. Fighting that instinct is super hard.