Open regedit and browse to: HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\Common
Under Common create a new key:
And name it Graphics
Under the new Graphics key create a new DWORD
Name it DisableAnimation and give it a value of 1.
Double check it is created in: HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\Common\Graphics
You can close regedit and because it is a HKCU change I recommend logging off and on of Windows. After this change I noticed and snappier Outlook environment.