Vertical Leg Crunch is an alternate version of the Basic Crunch. This version of crunch will ensure your lower back is always press against the floor whereas in basic crunch, some people have the tendency to raise the lower back.
Vertical leg crunch works the rectus abdominis. Just like Basic Crunch, it helps you [...]

Many people have weak abdominal and lower back, two muscle groups which are commonly neglected. Crunches strengthen and tone these muscles. There are many variations of crunch, but let’s look at the basic crunch this time. Basic crunch may look easy, but some people are doing it in poor form and making [...]

Bicycle Maneuver (Bicycle Crunch) is a great abdominal exercise to work on obliques (side of your abs) and rectus abs (the the long flat muscles along the front sides of the abdomen = 6-pack portion).
Steps:

Lie on your back on an exercise mat or carpeted surface. Make sure your lower back is pressed against the [...]