energy | World Gym | One World Running | sports bottles

Working up a sweat can have an impact on the environment. Here are a few tips to make your workout more eco-friendly.

Say no to towel service:
Instead of using the crisp white towels in the locker room, take your own towel to the gym and use it for a few workouts before taking it home and washing it in cold water. If just 1 percent of gymgoers stopped using the towel service, it would save 36 million gallons of water per day.

Recycle your workout gear:
Take advantage of companies with programs designed to recycle old gear, such as Patagonia, which collects worn cotton and fleece garments and turns them into new clothes, or Nike, which uses old running shoes to build tracks and basketball courts, among other things.

Hit the pavement:
Instead of running on the treadmill, opt for the sidewalk. By running outside twice a week over the course of a month, you’ll conserve the amount of energy required to watch television for 20 hours or to do 24 loads of laundry.

Join a green gym:
The Green MicroGym in Portland, Oregon, connects its cardio equipment to generators that help power the gym. Their spin bikes generate 50 to 100 watts of energy each, which is enough to power a stereo and a laptop or a 37-inch LCD TV. www.thegreenmicrogym.com

Other Programs to Try Bent on Learning, a nonprofit in NYC that accepts gently used yoga mats and other yoga gear. www.bentonlearning.org// Soles4Souls (www.soles4souls.org), Shoe4Africa (www.shoe4africa.org), and One World Running (www.oneworldrunning.blogspot.com) also accept donations of used sneakers.

More Green Gyms Around the World World Gym in Lowell, Arkansas (1607 North Empire Street, 479-372-4766, www.worldgymarkansas.com) //Ridgefield Fitness Club in Ridgefield, Connecticut (66 Grove Street, 203-431-7796, www.ridgefieldfitness.com) //Urban Fitness in Mexico City (Calle Cinco de Mayo 35, www.urbanfit.com.mx) // California Fitness in Hong Kong and throughout Asia (www.californiafitness.com)

Green Gear

Equipment designed for maximum performance -- and minimal environmental impact.

Forget plastic water bottles (Americans toss about 60 million per day). SIGG water bottles are made from durable aluminum and can be used over and over. The sports bottles are lightweight and have leak-proof tops. $25. www.mysigg.com

Atayne athletic shirts are made from recycled plastic bottles and coconut shells. The sleek tops are odor-resistant, offer UV protection, and are printed with slogans like, “Run Hard, Tread Lightly.” $38. www.atayne.com

Take a hike (or a run or a bike ride) in the Icebreaker Oasis Crewe top, made from natural merino. It’s a renewable and biodegradable fabric that wicks away moisture and feels silky smooth. $65. www.icebreaker.com

The Everything Fits Gym Bag is made of 100 percent recycled polyester. It has a roomy interior and adjustable straps that hold a yoga mat and a water bottle. The vented exterior compartment is perfect for shoes or wet clothes. $60. www.gaiam.com

The 100 percent degradable Yogamatic yoga mat is as chic as it is eco-friendly. It’s also bacteria resistant and is 50 percent lighter than mats made of PVC. $85. www.yogamatic.com