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  The abdominal region of the body is one of the most stubborn to exercise. A combination of age, gender and genetics play into the impact and effect that workouts will have on this area of the body. While abdominal exercises won't reduce body fat from the area, they will strengthen the muscles. Machines and equipment are not required to do an excellent abdominal workout, as most exercises focus on concentrated movement and body weight.
  
  

Standard Crunch

• The most basic and widely known abdominal exercise is also one of the most effective when performed properly. The standard crunch is good for the entire abdominal region, but is particularly focused on the upper abs with much less emphasis on the lower abs. Begin by lying on your back with your knees bent and feet on the floor. Raise your shoulders from the floor while keeping your head still. Lift slowly and squeeze the abdominal muscles throughout the movement. It is not necessary to touch your knees. Lower slowly and repeat. Place your hands across your chest for an easy exercise or behind your head for a harder exercise. Put your hands straight out in front of your head for the most challenging variation.
  
  

Double Leg Lift

• This exercise focuses on the lower abs. Begin with only a few repetitions and increase the number of reps as the muscles become stronger. Lie on the floor with your legs straight out, feet together and hands under your butt. Keep your palms to the floor. Slowly raise your feet off the floor while keeping them together. Lift them 6 inches off the floor and hold them there for a few seconds. Lower your feet to 1 inch off the floor and hold them there for a few seconds. Repeat the raising and lowering motion five to 10 times, holding in each position.
  
  

Reverse Curl

• The reverse curl focuses on the upper abs while engaging the side (oblique) muscles. Begin by lying on the floor with your knees bent. Place your legs as close to your chest possible while keeping your hips on the floor. Squeeze the abdominal muscles to raise your hips off the floor and bring the knees to your chest. Focus on slow, concentrated movement. Lower the hips and repeat. Keep your hands under your butt for an easy workout, or put your elbows on the floor and hands up in the air for a harder workout.
  
  

Side Lift

• Side lifts are specifically targeted to the side muscles in a way that none of the exercises mentioned above can. Start with only a few reps and as the muscles become stronger, add more to the workout. Begin by lying on your left side with your knees bent and together, your left arm lying out in front of you and your right hand placed behind your head. Squeeze your right side muscles to lift your right knee while moving your torso toward it. It is not necessary to touch the elbow to the knee. Lower back into starting position and repeat the exercise. Roll over onto the right side and repeat the exercise.
  
  

Double Leg Circle

• Another exercise concentrating on the lower abs are double leg circles, which should be done with a lower number of reps until the muscles become stronger. Lie on the floor with your hands under your butt and feet and knees together. Use your lower abs to lift both legs a few inches off the floor. While keeping your legs together, rotate both feet in a wide, clockwise circle. Do as many reps you feel comfortable (three to five to start). Lower back into starting position and relax for a few seconds. Lift your legs again and do the same number of reps in a counter-clockwise motion. Alternate clockwise and counter-clockwise for two to three sets.
  
  

Alternating Crunch

• The alternating crunch mixes alternating leg walks with a crunch for an advanced movement that engages the upper and lower abs, with a greater focus on the upper abs. Lie flat on the floor with your legs straight, feet together and arms extended over your head. Squeeze through the abdominals to raise your shoulders off the floor while bringing one leg straight up and your hands over your head. Continue the motion until your hands touch your foot. Lower to the starting position and repeat the motion with the opposite foot. Continue alternating legs while squeezing through your abs. Do not swing your arms or legs.