Shoulders up and knees in at the same time. That's the double crunch, and this double crunch counter measures it as a single fold, with your torso and thighs closing together.
You start flat on your back with your legs extended, and you finish by lowering both ends all the way. A mat under your back helps, and the coach calls each rep aloud once you've lowered back down.
Phone setup
Turn the phone sideways, rest it on the floor about 2 meters (6 feet) from you, and check the preview shows you from head to feet.
Lie flat and side-on to the phone, with your legs extended.
- Give the coach a moment after you lie flat; it confirms the start before the first rep counts.
Form cues
- Begin lying flat. Back down, legs long. Each rep starts and ends in that open shape.
- Meet in the middle. Bring your knees and shoulders toward each other. The fold has to close deeply for the rep to register.
- Use both ends. The app measures the fold, not which half did the work, so lift your shoulders and your knees.
- Lower both together. Returning all the way flat completes the rep, so don't stop with your feet hovering.
Common mistakes
- Tucking only the knees. A small knee tuck on its own won't fold deep enough. The double crunch asks for a deeper fold than a reverse crunch.
- Crunching with the shoulders alone. If your legs stay long, the fold never closes. Bring the knees up to meet your chest.
- Stopping before you're flat. The rep finishes when both ends come back down. Lowering only halfway leaves it open.
How FitnessBruh counts it
The angle measured is the hip fold between your torso and thighs, from shoulder to hip to knee. Lying flat is the start, knees and shoulders meeting is the far position, and lowering both all the way down completes the rep.
It needs a deeper fold than a reverse crunch does, so a small knee tuck by itself won't get there. And because it reads the fold, it can't say which half moved, which is why lifting both ends matters.
As with the sit up, counting begins after a moment lying back, and getting up off the floor pauses it until you lie back down.
FAQ
Does it check that my shoulders actually lift?
It measures the fold between your torso and thighs, not which end moved. Lift your shoulders and your knees both, because the counter can't tell which half is doing the work.
How deep does a double crunch have to be?
Deep enough that torso and thighs fold together. It asks for a deeper fold than a reverse crunch does, so a little tuck of the knees alone won't reach it.
Should my legs start straight or bent?
Start lying flat with your legs extended, like a long line along the floor. Each rep begins from that open position and finishes when you lower both ends back down to it.
