Exercise Library
Jackknife Sit Up Waist Max
On the Waist Max machine, you fold your torso and knees up simultaneously to meet in the middle, then extend back out under control. The machine's support lets you load the jackknife pattern more than you could on the floor alone.
Primary muscle
Primary: Rectus abdominis Secondary: Hip flexors
Equipment
Bodyweight
Category
Abs
Track This Exercise in the App
Log your jackknife sit up waist max sets in 1RM.fit and watch your estimated 1RM update automatically as you get stronger.