http://AsktheTrainer.com Personal Trainer Michael Behnken, MS, NASM-CPT-PES, CSCS V-ups are a great abs exercise which can be performed many different ways. The superior way to perform the v-up is to swing your feet and hands up and pause for a good amount of time, before you lower yourself back to original position. Your body type will determine which way to perform the v-up is best for you. If you have long or heavy legs, you may overload your hip flexors. A way you may try to combat this is hold a dumbbell or medicine ball between your hands. If you do not feel your abdominals fatigue, you may be better off choosing another ab exercise. San Francisco Personal Training http://fitSF.com