10 Minutes to Burn

BOXING CHALLENGE

The lowdown: A superchallenging arm, butt, and thigh workout consisting of real boxing moves created by Michael Olajide, owner of Aerospace, a boxing-inspired gym in NYC.

What you'll get in four weeks: An urge to shop for spring tank dresses early.

Special equipment: None, but use a punching bag and gloves if you'd also like to blow off steam.

Extra credit: Box with small hand weights (3 to 5 pounds).

How it works:

30 SECONDS Start in a boxing stance with your fists up, one slightly in front of the other, knees slightly bent, and jog lightly in place. Now do a jab - a straight punch with the right arm, keeping the left bent, as the right foot steps forward. Then jab left. Continue alternating and bring the shoulder forward when you punch.

1 MINUTE Squat, feet shoulder-width apart, arms stretched forward.

30 SECONDS Repeat alternating right and left jabs.

2 MINUTES Now do slow lunges: Step left foot in front and bend your left knee; keep elbows bent and fists up. Hold for 30 seconds. Then jump straight up and land in a lunge, this time with your right foot in front. Hold for 30 seconds. Repeat.

30 SECONDS Back in the boxing stance, do uppercuts: arms bent, elbows to floor, fists aiming upward. Continue alternating left and right.

2 MINUTES Repeat slow lunges.

1 MINUTE Now alternate left and right jabs with left and right uppercuts as you jog in place.

30 SECONDS Continue alternating jabs while in a squatting position.

2 MINUTES Get back up for left and right uppercuts, then squat for left and right jabs. Continue alternating.

GYMNASTICS STRETCH & CRUNCH

The lowdown: A gymnastics-inspired workout that stretches the muscles and provides a solid core workout.

What you'll get in four weeks: Better coordination and flexibility, and a smaller paunch.

How it works:

1 MINUTE 30 SECONDS Start with a plank and hold for a few moments. Move into five push-ups (use knees if necessary), then roll onto your back and flow right into sideways crunches: Knees are bent, with left foot on right knee for stability. Bring right elbow to left knee. Repeat for 30 seconds. Repeat on other side.

1 MINUTE Repeat crunches with straight legs in V position.

1 MINUTE Get in plank position and shrug shoulders for 30 seconds. Repeat shoulder-shrugging with forearm plank.

30 SECONDS Do V shoulder shrugs: Stand with feet together, bend down with arms in front, 6 inches from toes, palms down, hands together, with fingers creating a triangle. Shrug.

1 MINUTE Lie flat on floor with legs extended in front of you. Gently rock backward into a shoulder stand. "Your body weight should be supported on your upper back, and legs should be as close to vertical as possible," says Hector Salazar, gymnastics coach at Chelsea Piers. Support lower back with arms. Now rock back to seated straddle. Stretch gently to the left, then to the right, then middle. Continue repeating.

1 MINUTELunge with right leg in front. Bend forward, place palms on floor on either side of right leg. Slowly kick left leg up so that left leg is pointing close to the ceiling and right leg is perpendicular to it (like an L). Return to start position. Continue repeating for 30 seconds. Now do other side.

4 MINUTES Repeat exercises 2 and 3 twice.