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So you've been trying to go a little easier on Mother Earth by buying better-quality gear and hanging onto it as long as you can. But when the time does come to let it go—either you've got one too many tennis rackets, your yoga mat has seen better days, or your running shoes are down to their last tread—there's no need to add to our already overflowing landfills. Instead, give your gear a second life through one of these donation or recycling programs.

Nike recycles more than 1.5 million pairs of athletic shoes per year through their Reuse-a-Shoe program (they accept any brand or type without cleats). Parts of the shoes are turned into materials for track surfaces, flooring, and playgrounds. Still some life in your shoes? Donate them to Soles4Souls, which distributes new and gently used shoes to needy folks in 125 countries.

Yoga mats
Manduka collects worn-out mats as part of their Recycle Your Mat program, then turns them over to businesses that make goods from recycled materials. (They also offer a 20% discount on a new Manduka mat as a thank-you for your donation.) If there are still a few downward-facing dogs left in your mat, send it instead to the Bolder Mat Company; they'll donate it to a needy school or community organization.

Workout clothes
Patagonia wants their stuff back! Send your threadbare fleeces (both Patagonia and Polartec styles from other companies), Capilene baselayers, and Patagonia cotton T-shirts to their Common Threads Recycling Program so the material can find its way into new garments.

Sports equipment
Send Sports Gift whatever good-condition gear you have lying around—from baseball bats and soccer balls to jump ropes and Frisbees—and they'll distribute them to impoverished children in over 50 countries.

Fitness equipment
Instead of allowing that neglected treadmill to capture yet more dust, give a shout-out to Fitness 4 Charity. They'll match you up with a person or group who needs the equipment but can't afford to buy it.

Even though the earthquake in Haiti happened more than a year ago, those left homeless still need good-condition tents to live in while they continue to rebuild. Send the (waterproof) one you've got tucked away in the far corner of your garage to Tents 4 Haitians or Tents for Haiti so it can be put to good use.

Happy Earth Day!