7 tips for flat abs, with Brett Stewart

Is there anyone out there who wouldn't want a firmer midsection? Here, Brett Stewart, the author of "7 Weeks to 300 Sit-Ups" shows you how to get started on your road to rock-hard ab-dom.

1. Flat abs start with a strong lower back and hips. While abs get all the credit, you will not get that flat tummy unless you strengthen your hips and lower back.

2. Work your core first. Don't save it for the end of your workout when you're tired, sore and rushed for time. You'll notice what an important part your core plays in other exercises too, as these areas will be partially fatigued.

3. Great abs develop from full-body exercises. From squats to jumping jacks, every move that requires you to brace your core and stay vertical helps to sculpt your abs.

4. Do more planks. This fantastic core-strengthener is a no-impact exercise that works everything from your fingers to your toes. Be sure to squeeze your glutes to engage your lower back and hip flexors.

5. Have fun. Instead of always relying on the same machines, get out of a fitness rut and explore all the different types of equipment gyms offer. Stability balls are great for crunches, hip raises, reverse pikes, windshield wipers, etc., and doing squats and planks on a Bosu ball (above) will help you get that six-pack.

6. Look cool while you're building heat. Hanging leg raises, the farmer's walk and the overhead weighted walk are awesome - and unique - core-strengtheners. (A quick Google search can shed some light on these.)

7. You are what you eat. What you put into your body is directly responsible for the size and the shape of your midsection. The quickest way to get fit is to focus on lean proteins - grilled skinless chicken, lean beef and fish in portions about the size of your clenched fist. Add steamed or raw veggies and healthy starches like sweet potatoes. Try hard to avoid sugary foods and drinks.

Learn more about "7 Weeks to 300 Sit-Ups" and get more of Brett's fitness plans at 7weekstofitness.com