I quite often see riders wanting their horses to be more forward on a constant basis even though they are not quite up to being able to ride the horse in a correct forward manner consistently.
If you are just starting to work on impulsion make sure that you allow your horse to have some steady work incorporated into their routine. Whether it is during one of their work rides or take them out for a trail ride. If you constantly are asking your horse to go forward forward forward this is something that your horse will start to do all the time even if you are not asking for it. If you are up to that level - great! However if you aren't up to it just yet you will create a horse that is rushy and on the forehand.
Most Grand Prix dressage horses have hack days incorporated in to their training schedule so they can relax and enjoy a bit of downtime with their riding.
Keep your horses mental well being at the forefront of your riding and you will be guaranteed to have a happy horse!
Happy Horse = Happy Riding!