(Odd numbers engage your mind more than even ones, so you focus less on fatigue.)

It’s so quick, the big boss will never know you’re gone.

See the workout

Rowing Machine

Why wait for an open treadmill?

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The rower incinerates calories just as fastand you don’t even have to stand up!

This workout burns 226 calories (based on a 135-pound woman).

Practice good form: Lightly grip handlebars, and stand tall.

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You’ll burn about 290 calories!

But don’t worryyou won’t feel like you’re gonna die!

Give everything during the sprints and keep the recovery jogs slow.

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See the full plan (and get tons more ideas!)

The 22-Minute Calorie Blast With Kettlebells

Fat-fighting kickboxing meets the heavyweight champ of toning, the kettlebell.

The fierce matchup will catapult you into a calorie-zapping frenzy300 in 22 minutes!

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Plus: No equipment necessary!

And bonus: Before you have time to zone out, you’re moving on!

The 10-Minute Stair/Burpee Routine

So busy that you’re free to’t even leave the office?

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You’ll burn 100 calories in just 10 minutes.

See more ways to burn 100 cals in 10 mintues

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