Knee Support

Agreed, but wearing one can just get you through an important series.

My physio always told me that pain in my knee was a sign to stop. Pain in a muscle is usually not so bad because that is natural if you are building muscle.  Any form of sharp pain caused by poor support from your muscles is a sign to stop doing what you are doing.  A support can prevent this. Also keeping your body warm is never a bad thing when suffering from this sort of pain and a support will help this.

I would say that a support should still be worn while sailing for a few months but gym work outside of that without a support should be focused on the important muscle groups in your legs. Thats what I did and it worked for me. 

Obviously hiking style is the most important thing to consider. When I had knee trouble I tightened my toe straps and made sure i used the most efficient hiking style i could. My best lesson came from my old optimist squad coach who was the first person to teach me to hike with your legs in the lulls and your body in the gusts.  Basically meaning you should be aiming to lean back as far as possible all the time but keep your legs as far into the boat as possible while still keeping fully powered up. This seriously reduces the amount of time your leg muscles are doing all the work and allows you to sail for hours and hours without nearly as much pain. So bums in and heads back is the technique to master in marginal hiking conditions. Keeping a good straight back posture is important. (unlike the ones demonstrated by me in a few recent editions of the magazine in my laser! )