The main benefit to stability ball crunches is that they work your abs and obliques more effectively than regular sit-ups do because they force you to engage all parts of your core muscles at once--including those in your lower back, which are often neglected in other types of abdominal exercises.
Application: "6-Second Abdominal Trainer
Colour: Pink black blue
Applicable people: Everyone
Material: Manganese steel, foam, silica gel
Name: Suction Cup Abdominal Device Material: Manganese steel, foam, silicone Dimensions: as shown Weight: 1000g Color: pink, blue, black Applicable people: men, women, old, young Packing: 1 pcs Introduction to use: 1. Before use, please use a rag to wipe the floor and the abdominal curler clean. 2. Please place the curler on a smooth ground without any gaps. 3. Adjust to a suitable height according to your needs. 4. Press the black button then press down the abdominal curler with your fingers to make the machine and the ground completely contact, and the machine can be used after installation.