HOW: Start in a long sitting position holding only one weight in one hand in front of your shoulder. Begin the exercise by keeping the rest of your body still and performing an overhead press. Hold the overhead position for a moment (the weight should be in line with your ears), slowly lower the weight down and return to the starting position and repeat.
FEEL: This should feel like an upper body workout, specifically your deltoids, traps, triceps, and upper back muscles. You should feel your shoulder blade working a lot with this exercise. You will also feel your abs and lower body working to maintain optimal long sitting posture - avoid side-bending or tilting due to the off-set unilateral weight.
COMPENSATION: Do not excessively arch or bend your low back. Keep the rest of your body still as best as you can. Do not use momentum to move the weight, also focus on moving slowly, maintaining time under tension. Avoid excessive shrugging. Avoid leaning side to side.