May 17, - Girl Smarts Stop Everything: Kim Kardashian's trainer just shared her trainer, Melissa Alcantara has shared her go-to butt and legs workout with . How to: Start on all fours, with your hands and knees hip-width apart (a). The Best Butt Exercises for Knee Pain—No Squats or Lunges Included A. Stand with feet together, dumbbells in hands by sides. Shift weight into right foot.