In the past...

In the past, our ancestors used to stand up to work and sit down to rest. Today, we sit down to work and stand up to rest -- exactly the opposite of our nature!

So when you're at work, remember to take a break sometimes, stand up and stretch. Or do some Tai Chi for 5 minutes. Sitting still for too long can be dangerous!

http://www.mayoclinic.org/healthy-living/adult-health/expert-answers/sitting/faq-20058005