Sore hip flexors are a sign that those muscles are doing more work than they are accustomed to doing. For example, I snowshoe in winter. During the first outing of the year on snowshoes, hip flexors get a bit sore but are fine thereafter. In your situation, if moving the saddle did relieve pressure on your hands, then that was the correct thin to do but a whole inch (3-4 cm) is a great distance to move a saddle in one go. Try moving the saddle in smaller increments, say 3-4 mm) until a happy medium is reached.