Engaging your core all day can lead to some seriously toned abs, but did you know it can also help reduce tension and anxiety? We asked personal trainer Jessica Manning to share some of the biggest pluses to keeping your core engaged throughout the day.

1. Flatter abs
Engaging the core doesn't mean sucking in your tummy. In fact, the move is more like tensing your abdominal muscles into a protective ring around the torso. It's the muscle contraction that occurs naturally just before you laugh or cough. Constantly working that muscle group tones you inside and out. You'll look and feel five pounds lighter whenever you do it, says Manning.

2. Improved posture
Don't just "sit up straight"; engage your core for your best posture. "When the abdominals are loose and the lower back tight, people can hoard an extreme curve in the spine, affecting the position of the pelvis and, really, the whole body," says Manning. Maintaining good posture is important for protecting your joints, bones and muscles, which will reduce the risk of injury as you age, she explains.

3. Less back pain
Get rid of the tension in your back, neck and shoulders and make your workday a little more comfortable. "When the abdominals are pressed in, the spine is stretched straight," says Manning. "When the abdominals are loose and hanging forward, the lower spine gets scrunched inward. This is the most common reason why people are experiencing such terrible back pain, and it's the first place I start in correcting it."

4. Better breathing
Holding in your stomach encourages you to hold your breath, but when you properly engage the core, with the abdominals pressed inward, as opposed to "held in," your lungs have more room to breathe, says Manning. Deliberately breathing out all that stale air in the bottom of your lungs will help release toxins and boost your energy.

5. Reduced anxiety
Breathing from an engaged core leads to more mindfulness -- and less stress. "Breathing is about dismissing the bad with each exhalation and taking in all the good with each inhalation," says Manning. "By being conscious of your breathing, you can adopt this mentality, which is very cleansing and renewing, in the most natural and productive way we have available to us." The more you focus on your breath, the less you're fretting about your big presentation tomorrow.

Photography, iStockphoto.com.