A 120-second stretch improves postural control and plantar pressure: quasi-experimental study

BACKGROUND: There are no studies on long-term bilateral calf stretching in relation to balance and plantar pressure. OBJECTIVES: To demonstrate that there is better control of posture and pressures after continuous stretching of the posterior calf muscles. DESIGN AND SETTING: Pre and post-intervention study conducted in a private clinic. METHODS: We measured static footprints and stabilometry before and after continuous passive plantar flexor stretching of duration 120 seconds, among 24 healthy subjects. RESULTS: We found differences in Y displacement with eyes closed (P = 0.010), but not among other variables with eyes closed: X displacement (P = 0.263); surface (P = 0.940); laterolateral speed displacement (P = 0.279); and anteroposterior speed displacement (P = 0.914). There were also no differences in eyes-open variables: X displacement (P = 0.341); Y displacement (P = 0.491); surface (P = 0.167); laterolateral speed displacement (P = 0.852); and anteroposterior speed displacement (P = 0.079). The plantar pressures in the heel (maximum pressure, P = 0.048; mean pressure, P = 0.001) and in the midfoot (maximum pressure, P = 0.004; mean pressure, P = 0.004) were reduced, but not in the forefoot (maximum pressure, P = 0.391; mean pressure, P = 0.225). The surface became larger in the forefoot (P = 0.000) and midfoot (P = 0.021). CONCLUSIONS: Continuous static stretching of plantar flexors for 120 seconds improved stance balance and reduced plantar pressures (maximum and mean) in the rearfoot and midfoot. It also increased the surface in the midfoot and forefoot. TRIAL REGISTRATION: at clinicaltrials.gov, under the number NTC03743168.