Do you do regular ab workouts, but fail to see results? Are you struggling with low back pain? What about poor posture? Well, the most likely cause of all three of these problems is not knowing how to properly activate your core, says personal trainer and TODAY contributor Stephanie Mansour.
In fact, she called failing to engage the core the most common mistake she sees at the gym. Here's how to avoid it.
Trainer tip of the day: Learn to activate your core
“Not engaging your abs and specifically pulling the navel in toward the spine during all of your workouts is the No. 1 mistake I see people making at the gym,” Mansour says. "Many people don’t know how to engage their abs during exercises," such as lifting weights, squats, deadlifts or walking lunges, she adds.
Why it matters
Activating your core — which basically means engaging the deepest ab muscle, called the transverse abdominis — prevents pain and injury, especially in the back, improves posture, and makes your workouts more effective, since you're using more muscle groups.
How to get started
If you're unfamiliar with activating your core, a simple exercise called a pelvic tilt can teach you what it feels like: Lie on your back with your knees bent and feet on the ground. Try to make your back flat against the floor by tilting your pelvis up slightly and squeezing your abs.

Mansour recommends practicing the pelvic tilt before every workout to make it easier to engage your core.
TODAY's Expert Tip of the Day series is all about simple strategies to make life a little easier. Every Monday through Friday, different qualified experts share their best advice on diet, fitness, heart health, mental wellness and more.
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