• Use as much resistance
  that you can maintain full
  control with.
• Hold chest up and out.
• Maintain natural curve in
  lower back.
• Keep shoulder blades
  protracted apart.
• Do not hunch up your
  shoulders to neck or ears.
• Activate your T.V.A.
• Begin by retracting your
  shoulder blades together,
  not pulling with your hands.
• Then as you exhale, pull
  your elbows back without
  the pulling action coming
  from your hands, but from
  your back.
  
• Squeeze your back tight.
  
• Inhale as you return with
  your shoulder blades
  protracting apart and not
  your hands just returning.
• Do not round your back
  when returning or pulling
  the resistance, this will only
  work your arms.
  
  

All photos by Eric Jacobson