America’s obesity issue

The heart of the American obesity issue (epidemic?) is the simple idea that Americans consume more calories than they burn off. The excess calories are stored by the body as fat. This happens when either too many calories are eaten or when too few calories are exercised away. In the case of Americans, the answer is both. Americans are consuming more calories than they have in the last 50 years. According the USDA’s Agricultural Fact Book 2001-2002, the average American consumes roughly 2,700 calories per day. This is 530 more calories per day than Americans consumed in the 1970’s. Americans are consuming more meat and more cheese than ever before. There is also a trend of eating more refined and processed foods. More than half of the cheese that Americans eat comes in commercially manufactured and prepared foods, such as nachos, tacos, and fast-food sandwiches. What’s more, Americans are eating more fats and oils per capita than ever as well. In the 1950’s, added fats and oils contributed 41% of the total fat consumed by Americans. By 1999, this number had risen to 53%, probably due to the higher consumption of fried foods.

This increased consumption would not be so bad if Americans also increased their activity, but this is not the case. Only about 25% of Americans get the recommended 30 minutes of daily leisure physical activity. Even children are less active than they were before. A child between the age of 5 and 15 in 1995 would walk and bike 40% less than a child in 1977. There are many reasons for this. According to a video released by the Center for Disease Control, people are not active because it is dangerous to be active. Many cities lack bike lanes to bike and jog in, and also lack public transportation, which encourages people to drive to their destinations. Technology has also played a role in the sedentary lifestyle Americans. Americans today also sit in front of screens more than past generations both for work and pleasure. Americans work all day on computers then go home to watch television.

If America’s obesity problem is to be fixed, both consumption needs to decrease and activity needs to increase. Resolving one issue will not make America healthy again. We need to watch what we eat and exercise more. That is the only way.

How exercise can keep the lights on

This morning, as thousands of runners lined up for the Austin Marathon and Half-Marathon, I couldn’t help but think of how much human power each athlete generated as he or she covered 26.2 or 13.1 miles. What if we could harvest that energy and use it to supply electricity to part of Austin? One of the most widely known examples of human power being used to supply energy is Lance Armstrong’s 2005 Sports Center commercial.

So what does this mean for us? While funny, the commercial is a little bit off the mark. Not even Lance Armstrong could power an entire building. And well, none of us are Lance Armstrong. Sure, mapawatt says Lance can produce 400 to 500 watts while climbing up the French mountains, but he only generates about 250 watts when cruising. Mapawatt’s blogger estimates that he would need 1o of the world’s best cyclists working at their hardest to power his house with max air conditioning. Given the price of electricity, these highly-trained athletes would be making chump change.

In 2008, Portland’s Green Microgym became a leader in the harvesting of human energy, using the exercise of gym members to help power the 3,000-square-foot facility.  Closer to home, Texas State University is using its Student Recreation Center to make students aware of their energy consumption habits. The center’s “human power plant” is the largest in the world and uses 30 elliptical machines to give electricity to the campus power grid. It’s thought that the $20,000 project can pay for itself within 7 or 8 years. How Stuff Works estimates that during a workout, the average person can produce anywhere from 50 watts to 150 watts of electricity per hour, depending on the machine. Some machines even have outlets to power appliances using less than 400 watts of electricity. To put that in context, one could likely power a large TV during a workout but not a refrigerator; lightbulbs would be no problem.

Sure, using human power to provide electricity to our homes is not the most efficient or most cost-effective way of doing so, but the concept inspires each of us to not only put our workouts to good use but to also seriously contemplate our energy consumption. To find ways to make your home human powered, take a look at The Human Powered Home by Tamara Dean.