This document provides 5 killer fat loss workouts that can be completed in an hour or less and are suitable for busy people. The workouts include kettlebell interval workouts, Crossfit circuits, Tabata intervals, indoor rowing, and running. Kettlebell intervals involve alternating kettlebell exercises like swings with recovery activities. Crossfit circuits involve completing rounds of exercises like squats and chin-ups. Tabata intervals involve 20 seconds of high-intensity exercise followed by 10 seconds of rest for a total of 4 minutes. Indoor rowing workouts provide full-body cardio and include intervals and benchmark times. Running workouts include fartlek training with bursts of speed and hill sprints.