Dolphin Plank Begin in Down Dog. Lower onto your forearms and walk your feet out. Your body should be in one straight line with your shoulders directly above your elbows. Hold Dolphin Plank for five breaths. If it's too difficult, lower one or both knees to the floor. For more of a challenge, and to strengthen the upper body and core even more, do a few Dolphin Dives. Image Source: POPSUGAR Photography / Louisa Larson