• Your abdominals muscles, or abs, are part of your "core." That is, the muscles and tissues in your hips, legs, spine and shoulders. Strong core muscles help with stability and ease of movement in different directions, protecting your body from injury and helping to maintain your balance. According to Gray Cook, author of "Athletic Body in Balance", the best way to train your abs is to move your body in different directions in a standing, lunging or or split-stance position. Not only will you burn more calories while exercising, but you will also improve your strength and stability.
  
  

Push-up With Rotation

• Your abdominals work with your hips, back, and shoulders to stabilize your body while you do a push-up. Start in a push-up position with your hands slightly wider than your shoulders and your feet slightly apart. Keep your spine and hip in alignment like a plank. Lower your body down to the ground with your elbows close to your ribs. Exhale and push yourself up. Lift your right arm off the ground, out to the side, and rotate your body to the right. Extend your arm high, and look at your right hand. Hold the position for two seconds, and lower your right hand to the starting position. Repeat the next rep with your left arm. Alternate each arm for 16 to 20 reps for three sets.
  
  

Overhead Kettlebell Squat

• Squatting with a kettlebell with one arm over your head demands greater stability in your core. Stand tall with your legs shoulder-width apart and your toes pointing forward. Hold a 15-pound kettlebell above your head with one arm fully extended. Squat down as low as you can while keeping your torso upright. Look up as you squat deep. Hold the squat position for two seconds and stand back up. Do not bend your arm or hunch forward. Do 10 squats for each arm for two to three sets.
  
  

Ball Crunch with Tubing

• Loop the tubing around a hook or a sturdy support and sit on a stability ball. Roll out so that your lower and mid-back is on the ball. Place your feet hip-width apart with your knees bent at about 90 degrees. Hold the handles of the tubing above your head. Exhale and lift your shoulders off the ball without pulling the tubing with your arms. Lower your body down and do 15 to 20 reps for three sets.
  
  Adding a rubber tubing for resistance for the ball crunch requires you to control your movement in all ranges of motion. Otherwise, when you lower your body on the ball without control, you can lose your balance and fall off.