I added weight lifiting (mainly leg press - I prefer multi-joint exercises so I can get my workouts finished more quickly ) squats and lunges (watch those knees to make sure they don't pitch too far forward ) and noticed a lot of improvement. I also have a trainer, so an occasional work out on that is: I pick a gear that allows me to go only 60-65 rpm and my goal is 20 minutes. I started with 5 minutes and worked up from there.

Good Luck! Looking forward to hearing about your successes!!