To add to the effects of sitting for long in a state of inactivity, it can cause Deep Vein Thrombosis (DVT) which can dislodge and form an embolus which travels to the lungs to block the vessels, stopping blood supply and causing immediate death or going to the brain to occlude it still and cause stroke in patients with Atrial Septal Defect.

God bless you for this post @onceuponatime