lab lunging at bikers, runners

Question
My rescued (at one year) 18 month old yellow lab is slowly but surely getting better at walking without too much pulling, however she consistently aggressively lunges at bicycle riders, skateboarders, runners, etc.  I can usually restrain her with lots of effort, but it seems like there should be an easier way.  She wears a gentle leader head collar, but this doesn't help this problem.

Answer
Usually the Gentle Leader is quite effective with such problems.  Perhaps your dog didn't read the blurbs that came with the packaging.  Dogs are individuals and sometimes fail to respond to what usually works.  I don't like them, but perhaps you need to try a prong collar.  Unlike the Gentle Leader, they are not something the average dog owner can go out and buy and use safely and effectively.  A prong collar needs to be carefully fit by somebody that knows how.  Maybe the best thing is to sign up for an obedience class and let the instructor help with the collar.  Most obedience instructors use them with more difficult dogs.  

The obedience class should also establish you as top dog.  The key to most behavior problems is approaching things using the dog's natural instincts.  Dogs see all the people and dogs in the household as a pack with each having their own rank in the pack and a top dog.  Life is much easier if the 2 legged pack members outrank the 4 legged ones.  You can learn to play the role of top dog by reading some books or going to a good obedience class. A good obedience class or book is about you being top dog, not about rewarding standard commands with a treat.