Black Friday may be the biggest shopping day of the year, but Cyber Monday gives you a chance to get great deals without setting foot in a crowded mall. According to the National Retail Federation, an estimated 127 million people plan on taking advantage of Cyber Monday sales this year.

While you may be in gift-giving mode, today is a good time to treat yourself to some new workout gear: many popular brands and retailers are offering big discounts on fitness gear and accessories.

Here are 15 reasons to do some online shopping today—just don't let your boss catch you.

Amazon.com

Up to 25% off Asics clothing and 40% off Polar heart-rate and fitness watches.

Athleta

20% off your entire purchase in stores and online with the code "CYBER20" at athleta.com

C9 by Champion at Target

Apparel: Buy 1, get one 60% off at target.com

Champion

40% off select items plus free shipping at hanes.com/champion

City Sports

30% off full-priced styles and clearance with the code "CYBER" at citysports.com

Dick's Sporting Goods

25% off plus free shipping at dickssportinggoods.com

GapFit

40% off with the code "CYBER" at gap.com

Lucy

40% off all bottoms plus free shipping at lucy.com

Lorna Jane

20% off plus free shipping at lornajane.com

New Balance

20% off plus free shipping at newbalance.com

Nike

Extra 25% off clearance with the code "DOMINATE" at store.nike.com (valid through 12/2)

Oiselle

20% off select apparel with the code "WISHLIST" at oiselle.com

Puma

20% off orders $75, 30% off $100, 40% off $150 or more, plus an extra 20% off sale styles at puma.com

Reebok

40% off plus free shipping with the code "HOLIDAY" at reebok.com

Sports Authority

25% off plus free shipping at sportsauthority.com

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