Whether you practice equestrian sports recreationally or (semi) professionally; make sure you are as fit as your horse.
Usually all attention goes to the training of your horse but for a "performance" you are jointly responsible.
Your own fitness ensures that you have a good time together. Posture, balance and condition are parts that are extremely important for your horse but certainly also for you.
A regular training focused on your sport can help you enjoy your sport together.