The v-sit is an effective abdominal and core exercise that works the rectus abdominis, the external obliques, and internal obliques. This exercise also engages the hip flexors.
To do the V-sit, start in a seated position on the floor, contract your abdominal muscles and core, and lift your legs up to a 45-degree angle as pictured. Reach your arms straight forward or reach up toward your shins as you are able. Maintain good core posture and a strong spine while you hold the position for several seconds. Rest and repeat several times. As you get stronger, hold the position longer.