1888 Boxing Training Manual

I haven't read through it yet. I thought it would be interesting for discussion though.

 

'If going into regular training, or if you are past the
halcyon days of five and twenty or thereabouts, and
find you have a tendency to “put on flesh,” the walk
will have to be alternated by an occasional run of a
couple of miles at a fair jog-trot, and if it is necessary
to “fine down” considerably, you may be forced to
run and walk in heavy “sweaters.” If you are out of
condition and perspire very freely, remember to rub
down with a coarse towel until you are perfectly dry;
and that to be sponged off with alcohol, or with any
cheap, raw spirit, is also a great comfort and refresh-
ment for weary limbs.'

Advocation of Fartlek training for beginners, page 48. This is basically common sense though.

Also I think you would appreciate some of the images presented. They are very detailed in showing techniques.

 

Interval training was actually used in the bronze age for horses, I think that practice was lost for a long time after though.

https://en.wikipedia.org/wiki/Kikkuli