It's Friday afternoon — do you know what's stored in your trunk?
Seriously though, many of us stow stuff away and forget all about it. Depending on the weight of what lurks in your trunk, you could be hampering your gas mileage. An extra 100 pounds of cargo can lower your fuel economy by up to 2 percent.
This is even more true if you drive a small- to medium-size vehicle — extra relative weight drags down smaller cars than the SUVs and trucks of the world.
Here's another twist on this problem: we weigh more than we should, and a lot more than we used to, and that makes the vehicles in which we ride less efficient. According to research by professors from the University of Illinois and Virginia Commonwealth University, Americans annually use about 1 billion more gallons of gas than in 1960.
Why? Because of the obesity epidemic in the United States. From 1960 to 2002, the weight of the average American increased more than 24 pounds, according to the U.S. Department of Health and Human Services.
So, this weekend, it's time to finally unload your trunk full of recycling, books to donate, tools, bags of mulch or whatever else is hiding in your trunk. And hit the gym.
John Rockhold is a green car enthusiast and Contributing Editor for MOTHER EARTH NEWS. Find him on Google+.