FG: One other question, to do with the 180 formula as well, when people are a little bit older, for example are 50 or 60 years old like my parents, and they run somewhat irregularly, or don???t at least have that base of two years of consistent training, would they really have to be training at 180-60-5, which is an HR of almost 115, for them it???s often basically walking, with part of it as slow