'Tip-toes' is a simple exercise that you can do in the early stages of knee rehabilitation.
In case you cannot see the video, here is a still sequence -
 |
The 'tip-toes' exercise strengthens the calf muscles but is also useful to re-train your balance. |
 |
Stand comfortably near a support such as a wall. |
 |
Go onto your tip-toes for 5 seconds. Repeat this 5 times. |
-