Changing hotbar slot whilst sprinting.

My sprint key is 'r' whilst sprinting using that key I can not use the item in slot 2 of the hotbar but I can use the others. This does not happen whilst sprinting using the w key twice.

What I expected to happen was...:
I expected to hold my sword in slot 2

What actually happened was...:
I couldn't use it!

Steps to Reproduce:
1. Set the sprint key to 'r'
2. Put anything in slot 2
3. sprint and WHILST sprinting try and select the item in slot 2