Renegade rows
An intense core challenge and strengthens the upper back and arms.
Assume a prone plank position, legs wider than shoulder width, wrists under shoulders, gaze 20cm in front of your fingers. Place one hand on a kettlebell. Squeeze your butt, thighs and core. Row the kettlebell up towards your hip, then lower. Keep your hips square. Do all the reps on one side, then switch.