This nasty combo destroys your legs and lungs and is surprisingly taxing on your upper back as you struggle to hold the position. It's best performed on leg days as a finisher.

How to Do It

  1. Do 5 kettlebell swings.
  2. Without rest, do 5 goblet squats.
  3. Again without rest, do 5 step-back lunges per leg.
  4. Repeat as many times as possible in 8 minutes.

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