I am wondering if this…thing I’ve been doing lately has any name. I find it a good and heavy exercise for the abs and core generally, although it might have some bad consequences - none I can think about, though.
Dumbbell-bench-press position; lift yourself up to sitting position, and return to starting position. Repeat. If done with a good amount of weight, I find it useful.
I always thought the abs were only in use for about the first 10 degrees of upward motion… doing sit ups does not give any benefit to working abs by doing just crunches. After the first ~10 degrees your hip flexors start to kick in.