I think when I first started, 7 mins was my limit. Keeping in mind that I hadn't worked out in YEARS when I first started.
I also found that - for me - if I could make it past the 11 minute mark, it got easier. I have no idea why 11 mins was my magic number, but it really helped me mentally to hit that point ... it's like I hit my stride or something.
AT this point I *can* do an hour or more. I don't want to.
I usually do 30-40 mins of HIIT on the elliptical, when I do it.
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