Could low iron, protein contribute to soreness after exercise?

Getting sore after every workout could be due to issues of training or one's diet. Assuming that you are training smart, i.e. with a steady pattern, regular rest and good biomechanics, then dietary deficiencies may be involved. One can certainly be a vegetarian and a high-level athlete.

There are many examples of outstanding athletes who follow vegetarian diets. Some vegetarians, however, are deficient in protein, iron and certain vitamins and minerals, which can be associated with muscle soreness.