Ulysses' books for 50+ continue to sell well year after year, with 90,000 copies shipped Author's previous book, End Everyday Pain for 50+ averages 60 copies a week on Bookscan Studies show that interval training is the most effective exercise for strengthen and repair muscles of seniors Features a customizable HIIT program with step-by-step photos and illustrations of stretches and exercises Author is an osteopathic physician.