so my abs burn.. my hip flexors are on fire. i can push it.. but during certain excerces, my lower back starts to cramp up.. right around the tail bone area. maybe a bit more.

usually when doing any ab routine where we lift our legs into the air while on our back (during the "pulse" movement, bicycle, etc).

what am i doing wrong? is it my technique? weak lower back that will strengthen in time? it's very frustrating to have this happen while i'm in the middle of workout.

please help!

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