For perspective, this is about half the CO2 that you will exhale in a year of normal breathing. For similarly useful environmental tips, try not exercising as much - wouldn't want to increase rate of exhalation!
I am not sure this argument is correct. Animals have a carbon footprint. More importantly, it seems like control over data is a stronger concern than a such a small amount.
The CO2 we exhale does not contribute to climate change because it comes from plants (and indirectly animals) that captures it back.
If you burn coal to produce electricity, it releases CO2 in the atmosphere and it will take a long time to sequester that CO2 back into fossil fuel.