The abdominal muscle group is the strongest muscle group in the body, and it influences every physical activity you can imagine. From sitting in a chair and walking in the park to running and throwing a ball, all are influenced by the ability of the strength, speed and coordination generated to be fluidly transmitted across the lower and upper halves of the body. The pivot here is abs. Weak abdominals become black holes, energy sinks in, and we lose strength and momentum. Our coordination suffers. We fatigue more easily.
Training the abdominal muscle group is no easy task. The muscles do not all respond to training at the same rate, and there is a core group of abdominals running beneath the external ones with muscle fibers pointing the opposite way. This makes for a core picture that no single exercise can adequately address, which helps explain why strong abs are hard to attain, which makes them an aim to strive for.
The Five-Minute Plank is a paradox of sorts. It uses relative inactivity to challenge the abdominal muscles and strengthen them. In five minutes you get to exercise as many parts as possible of the muscle wall. The result: strong abs, a strong core, more power, better coordination... plus you get to look good on the beach.
What it works: Abs, chest, glutes, lower back & core
Tip: To gain the maximum out of your time in this exercise, tense your abdominal muscle group at each rep.