While night splints are not fun to wear, they do offer an amazingly effortless way of reducing those brutal first steps of intense pain that most plantar fasciitis sufferers experience each morning. This is because night splints work by preventing the overnight shortening of the calf muscles and plantar fascia while sleeping.
The reason for this is that when we sleep, our feet go into a plantar flexed position. This means the feet are pointing downwards, causing the calf muscles which are attached to the Achilles tendon to shorten and increases tension on the Achilles tendon which results in tightening of the plantar fascia.
When you wake up in the morning and place your feet down on the floor to get out of bed, the Achilles tendon and plantar fascia have to immediately stretch back to the ankles neutral position in order for you to get your heel to make contact with the ground. This rapid change in tendon and fascia length causes pain in the plantar fascia, which is why you get this immediate discomfort in your foot.
By wearing a night splint while you sleep, your calf muscles and plantar fascia stay in a neutral position. Not allowing the shorting of your calf muscles or plantar fascia. So in the morning, when you place your foot on the floor, your plantar fascia only has to stretch very slightly and you avoid morning foot pain!