1. How do you sit?

Sit up straight on your chair with your back against the backrest. Which of these best describes you?

Using a footrest can help you sit comfortably. 
It is preferable for your desk to be lower and your feet flat on the floor. If that isn’t possible because your desk cannot be lowered, you can still achieve a good spread of your weight across your feet and upper legs/rear this way.

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