What to do with a horse that tenses when the aids are applied?

What should you do when riding a horse (English) that tenses up often when asked to speed up, slow down, or change gait? My horse has arthritis, before I started giving her liniments and stretching exercises a month ago that freed her movement, she developed a habit of tensing up when the aids were applied because it used to make her feel more sore. She isn't sore in hand or on lunge, only when ridden bareback or under saddle, halter or bridle.

the saddle might not fit right anymore.horses change physically.bareback? I wouldn't ride an arthritic horse bareback.arthritis doesn't go away.it's there. always.riding with a good fitting saddle and a nice soft bit like a plain smooth snaffle (myler comfort snaffles) with good soft hands, using one rein only as an aid, not closing on both hands at once.transitions.lots of walking. slow to quicker to slow and repeat. as a warm up.

It sounds like the arthritis bothers her under the extra weight that you add, although only a vet or equine chiropractor will be able to tell you if this is true and if there's anything that can be done about it. If it's indeed just a habitual issue, a proper warm up and more work on a loose rein and using your seat more as an aid will help. Be sure to relax and breathe deeply, often without realizing it we tense up when preparing to cue the horse which in turn makes the horse tense up. Also be sure you're well balanced when transitioning so that she can relax and move naturally. Finally working in half seat for a while might help, as will practicing fluid transitions frequently. Good luck!