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About 5 times per week for 6 months. The exact workout is from 19m28s - 37:22 in this video: https://www.youtube.com/watch?v=y0WOTplwNlw&t=19m28s (I do the whole thing twice, then 3km run then stretch) Imbalance is something that worries me. I figure it's better to do a workout that's imbalanced than to come up with a theoretically perfect workout that requires a gym that I hate going to or, worse, doing no structure…
Pulling movements in general are pretty hard to do with just calisthenics. Anywhere in that big park, is there a nice sturdy pole or post? If so, you can get an elastic band set, usually very inexpensive and portable, and use that to do rows (and face pulls, if you want). I would also try to incorporate pull-ups (some parks have pull up bars, or you can install one at home) to work your lats. This might be tricky if…
I'll incorporate pull ups as of today on every day except where the bar is taken, as that would negate one of the joys of this particular workout: that it can be done absolutely any time without planning/thinking/waiting.
Will research bands and band exercises (on youtube?) and almost certainly buy some and incorporate a few. Very much like the idea of some sort of 'row' as well as shrugs for traps. Forearms seems to already get smashed during pushups (especially the 'fingers out' and 'narrow grip' push ups [1]).
Will check out banded ab exercises too.
Thanks for the advice.