This is easy to do while I eat breakfast and read the paper after my run. When frozen, this makes a mushy mixture. Wrap it in a towel and attach it to whatever hurts with an ace bandage, then chuck it back in the freezer when you're done. Put my leg up whenever I'm sitting for a long time. Sitting with my knee bent hurts after a while.
Some chairs are worse than others.
I find airliner seats and automobile bucket seats to be particularly bad. Hope this helps. Chuck Barbee Thanks very much to the responses regarding running ultras after a person has had substantial cartalige removed due to surgery. All long runs should be done on trails if at all possible. Utilize regular weight training to strengthen the muscles that support the knee and help absorb the impact of each foot strike.