Commando plank: the 3-minute full-body exercise trainers recommend

The commando plank is a dynamic variation of the standard plank in which you alternate between a high push-up position and a forearm plank. The constant transition forces the core, back, glutes, shoulders and triceps to work simultaneously, making it far harder than a static hold. Personal trainers recommend three minutes of the exercise for anyone looking to improve whole-body stability.