Which filter do you like most for general moderate exercise? I see that they sell several grades of filter based on air flow capacity. The one for asthma seems

Which filter do you like most for general moderate exercise? I see that they sell several grades of filter based on air flow capacity. The one for asthma seems to be the most restrictive, but most effective. And the racing ones are opposite that, and the sports one is in-between. I'm thinking I would get the asthma one for myself, despite wanting to use it for exercise.