Jen Gee wrote:

Hi, feeling these in my lower back, back gets really fatigued middle of second set. I have to stop at 10 reps for last set. I am engaging core and using a 25 lbs DB. What am I doing wrong? Also is the weight evenly distributed to the knee on the bench and the standing leg foot? Or more weight on foot? Thank you…. Jen Giczi

Try going a little lighter and really focusing n engaging your hamstrings and glutes instead of your core as much. your lower back is part of your core, so instead, really activate your hamstrings and glutes 😉