Plaza Statement - Standard dancers...... train your shoulders.
In the Standard dances fatigue is noticed first in your frame and hold, in my opinion to much stamina training for dancers is focussed on the legs and feet!
When doing your exercises in the gym or running outside than try to run or do some exercises in dance-hold or raise your arms in or above shoulder height.
A good exercise as well is to keep the dance hold for approx. 20 min