This means sealing air leaks around windows and doors, properly insulating attics, replacing standard light bulbs with compact fluorescent lamps and giving your heating and cooling systems an annual checkup to ensure they're running properly.

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Sealing up cracks and openings where air can leak into and out of your home.

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Stray-Gundersen worked for the Norwegian Olympic Committee from 1997-2002, sealing bedrooms of the country's top Nordic athletes and adjusting the oxygen and nitrogen content of the air, so they could sleep in a simulated high altitude environment (he was the scientist who developed the concept of living at high altitude to increase hemoglobin levels).

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