Plantar fasciitis (PF) is a common running injury associated with low arch height, and excessive loading and pronation. Research has shown gait alterations in individuals with PF including increased rearfoot eversion, forefoot plantarflexion, and MTPJ dorsiflexion, and reduced center of pressure (COP) duration at the heel. Changes in kinematics and COP trajectory may affect dynamic stability. Therefore, dynamic stability as measured by time to contact (TtC) may be reduced in runners with PF. PURPOSE: To determine differences in dynamic stability during the stance phase of running in individuals with PF. METHODS: Twenty runners were separated into two groups based on injury status (1: PF; 2: healthy). Kinematic and kinetic data were collected at 200 and 1000 Hz, respectively, as participants ran at 3.5 m/s ±5%. TtC of the COP to the medial and anterior boundaries of the base of support were calculated over the stance phase. Minimum TtC values were determined for each portion of stance per trial, averaged across five trials per participant and across participants per group. Differences in TtC between groups during early, middle, and late stance were determined using one-way ANOVAs with alpha level set at 0.05. RESULTS: Group demographics were similar. TtC was similar between groups during early and late stance and different during mid-stance (Table 1). CONCLUSION: TtC was similar between runners with and without PF during early and late stance which may be related to inherent instability in transition phases. Runners with PF had reduced TtC during mid-stance suggesting a more rigid control strategy reflecting the injured state and increased potential for loss of balance.
Table 1. Results for demographics and time to contact (TtC) for runners with and without plantar fasciitis (PF). * = significant difference (α=0.05).

	PF	Healthy	p-value
Age (years)	42.90 (10.76)	38.20 (10.94)	0.35
Height (m)	1.660 (0.090)	1.660 (0.080)	0.90
Mass (kg)	67.73 (12.89)	64.99 (10.52)	0.61
TtC Medial Early Stance (s)	0.021 (0.018)	0.026 (0.024)	0.59
TtC Medial Mid-Stance (s)	0.099 (0.076)	0.185 (0.098)	0.04*
TtC Medial Late Stance (s)	0.041 (0.034)	0.064 (0.037)	0.15
TtC Anterior Early Stance (s)	0.074 (0.034)	0.104 (0.032)	0.05
TtC Anterior Mid-Stance (s)	0.172 (0.157)	0.392 (0.228)	0.02*
TtC Anterior Late Stance (s)	0.061 (0.091)	0.141 (0.097)	0.07