I would support changing “dangerous” to “incorrect”, as your post supports the latter claim but not the former.
I find it hard to correct you on this, though, because high-intensity cardio training is important and achievable; not for everyone, of course, but the people who can’t do it have problems like clinical obesity, severe physiological disabilities, and so forth; the “newbie” to exercise can perform and benefit from high-intensity, but are likely to conclude they can’t.
I would support changing “dangerous” to “incorrect”, as your post supports the latter claim but not the former.
I find it hard to correct you on this, though, because high-intensity cardio training is important and achievable; not for everyone, of course, but the people who can’t do it have problems like clinical obesity, severe physiological disabilities, and so forth; the “newbie” to exercise can perform and benefit from high-intensity, but are likely to conclude they can’t.