If you're aiming to get a flatter stomach at 50, we have just the tummy-tightening challenge that'll leave your core lean and toned if you stick to it. You may already be aware of the benefits of staying physically fit as you age. Exercise helps maintain and enhance your strength, gives you the energy to do the activities you love, improves your balance, decreases stress, and helps you get a good night's rest. Plus, it's a total mood-booster. That all sounds pretty appealing, right?