Here is a guy who has experimented living 'energy positive' for many years[1]. Meaning he tries to get more energy out of farming that he puts into it. In his calculations it does not make sense even to use a horse. Seems pretty tough, I think hunting and gathering would be easier way to go if you had access to the land.

Good writeup, but unfortunately in finnish.

[1]http://rihmasto.fi/artikkelit/elamamme-perusteista

(google translate) https://translate.googleusercontent.com/translate_c?depth=2&...