Impact of anti-gravity muscle training protocol on plantar pressure, pain threshold and foot posture on chronic painful heel: an RCT study

Abstract

Chronic painful heel (CPH) is a symptom of an underlying condition caused due to obesity, excessive foot pronation, tightness of Tendo-Achilles (TA), excessive running, and sedentary life. The antigravity muscles (AGM) atrophy results due to long working hours in sitting, leading to their deteriorating relationship with gravity thereby reduced sensitivity to its force. Hence, need arises to explore training effects of AGM protocol on CPH condition. A randomised controlled trial was conducted on thirty individuals with CPH allocated randomly to two study groups viz. AGMT (n = 15) and Control group (n = 15) who received intervention for twelve sessions over four weeks. Control group received conventional physiotherapy in form of therapeutic ultrasound and exercises while AGMT received conventional physiotherapy using the AGMT protocol. Outcomes assessed were plantar pressure and foot posture assessed using Harris mat, muscle strength by dynamometer, pain threshold with pressure algometer, and foot functions using Foot and Ankle Ability Measure Scale (FAAM) which were taken at pre- and post-training. The between group analysis of data revealed that foot posture, plantar pressure and muscle strength, pain threshold were significantly better in the AGMT group than in the Control group ( 0.0001), while pain intensity (P = 0.3952) and foot functions (P = 0.2372) were equally effective in both the study groups. In conclusion, the AGMT protocol along with conventional physiotherapy proved to be a promising training protocol for individuals with CPH showing positive outcomes in comparison to conventional therapy alone, suggesting to incorporate AGM strengthening alongside conventional therapy to obtain better clinical outcomes. Trial registration: This trial was prospectively registered in the Clinical trial registry of India with registration number CTRI/2022/10/046138.