Fire up your upper body with this 35-minute strength burn that incorporates full-body and core moves. Grab a challenging pair of dumbbells and work through 4 circuits, each containing 5 exercises—no repeats! Sweat through bicep curls, cross-body punches, weighted sit-ups, and more before finishin...

:45 work / :25 rest

-In-out Crunches (single to double)
-Single Leg Stretches
-Right Single Arm Situps
-Left Single Arm Situps
-Plank Knee Drive Hollow Body Lifts
-Glute Bridge Arm Raises
-Bicycle Crunches
-Inchworm Walk Out
-Plank Rocks