Achilles tendinitis, plantar fasciitis and even pain in the ball of the foot are often caused or complicated by tightness of the Achilles tendon. Stretching the tendon a few times a day helps, but using a night splint gives you a continuous period of stretching at a time you are less likely to guard or fight against it! In addition, when we sleep and rest, our ankle falls downward from the leg which places your tendon in a more relaxed position where it can more easily remain tight.