Dressage is mentally a big workout for your horse, in addition to the
carraige, impulsion and bascule. Keep it up and count it as one day in
your weekly workout!!! It sure makes my rides out on the trail such a
pleasure!! and my mare wears out her back shoes first.
Ok my twice weekly dressage lesson are typically an hour,
but we are trotting and cantering a significant amount of that hour, also
doing leg yields, spiralling in and out of a circle, etc. She can get
pretty sweaty doing that. So figure, trotting 7 mph, cantering 12 mph
(is that an unreasonable assumption?) I suspect we are doing about 8
miles. As Stagg is only riding for 40 minutes it will probably be
less but it is in the sand I am on pretty cushy footing (crushed
Nikes). My mare isn't conditioned for 50 miles but she is looking
pretty buff. I certainly am not saying they don't need more miles
over terrain but I think it is somewhat of a work
out.