Ultimate Performance Plantar Fascia Sock Neoprene This spike is great for This spike is great for middle distance rookies trying to discover their best event and for veterans working to take their racing to the next level essentially providing flex grooves into the midsole The Ultimate Performance® Ultimate Plantar Fascia Sock is a knee high sock designed to be worn overnight to help reduce and relieve the effects of Plantar Fasciitis when stretched for a sustained period (overnight) the tissues are encouraged to repair and heal in a better position which helps to reduce and alleviate the symptoms of plantar fasciitis and related heel pain