8. Sprints: To get extra speedy, make sure form fits function. Hold the correct posture, with eyes up, chest tall, shoulders relaxed, and arms swinging up and down with the elbows at 45-degree angles.
9. Stationary Bike or Rower: Hopping on the bike for a quick spin is pretty self-explanatory, but the indoor rower is a bit trickier. First, strap feet into the foot stretchers, sit up tall, and grab the handle. Roll forward until legs are completely bent and arms are reaching forward.
From this starting position (called the "catch"), explosively drive the legs back. When the legs are nearly extended, swing the torso back and pull the arms in so the handle is almost touching the rib cage. From here (aka the "finish") recover by stretching the arms straight out, returning the upper body to a straight, vertical position, and bending the legs back to the catch.
10. Russian Twist: Sit on the floor with the knees bent and feet together and lifted a few inches off the floor. With the back at a 45-degree angle from the ground, move the arms from one side to another in a twisting motion. Go super slow, twisting the shoulders completely from side to side.
11. Ski Abs: Start in pushup position with hands under the shoulders and core engaged. Jump the feet to the left side of the body, as close to the upper torso as possible. Jump the legs back to a straight plank position and repeat on the right side.
With the exception of the weighted movements, most of these can be performed anywhere, any time. All you need is a set of comfy clothes and a serious work ethic. To make keeping track of the time easier, consider downloading a Tabata timer app. Again, consider meeting with a trainer to go over correct form (even if you've previously done these moves) before starting a Tabata fitness regimen to prevent injury.
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