No, flat or heel-less shoes are not good for Achilles Tendonitis and are not at all recommended by doctors. This is because flat shoes, which comprise minimal support for your heels, force the Achilles tendon of your feet to work heavily in order to maintain the footwear and the feet in the same alignment, thus worsening the condition. With flat shoes, your Achilles tendon and the calf muscles will get sore, thus inflaming your Achilles Tendonitis more. So, podiatrists always advise Achilles patients to wear the best walking shoe for achilles tendonitis that are cushioned and possess at least one inch of heel.