BACKGROUND: Femoroacetabular impingement syndrome (FAIS) is a hip-joint disorder characterized by abnormal bony morphology (femoral-sided, “cam”; or acetabular-sided, “pincer”). FAIS is a precursor to hip arthritis and is often associated with low physical activity (PA) due to pain. Previous studies have relied on self-report questionnaires to assess PA. Device-based measurement (e.g., accelerometry), specifically step-based metrics (e.g., steps/day and cadence indices), may offer a more comprehensive assessment of PA patterns in this population. METHODS: We recruited 25 participants with FAIS (age=31.0±9.2 years, 60% women, BMI=26.1±4.7 kg/m2) and 14 healthy controls (age=28.1±9.1 years, 64% women, BMI=26.3±3.4 kg/m2). Participants were categorized as Cam only, Combined (cam and pincer), or Healthy (controls). Participants wore a waist-mounted accelerometer (ActiGraph GT3X+, ActiGraph LLC, Pensacola, FL) for 7 days during waking hours. Step-based metrics were computed, including steps/day, peak 1- and 30-min cadence (PK1 and PK30; steps/min), and time spent in various cadence bands (1-19, 20-39, 40-59,⋯100-119 steps/min). One-way ANOVAs with post hoc testing were conducted to examine group differences. Effect sizes (eta squared; η2) were calculated and interpreted as small=0.01, medium=0.06, and large=0.14. RESULTS: We found significant group effects for PK1 and PK30 (p=0.02 and 0.05, η²=0.29 and 0.25, respectively). Post hoc tests showed lower PK1 and PK30 for Cam vs. Healthy (p=0.003 and 0.005, respectively) and Combined vs. Healthy (p=0.02 and 0.05, respectively). Similarly, there were main effects for time spent in slow, medium, and brisk cadence bands (60-79, 80-99, and 100-119 steps/min (p=0.004, 0.02, and 0.02; η²=0.27, 0.26, and 0.19, respectively). Post hoc tests indicated differences in time spent in these cadence bands for Cam vs. Healthy (p=0.007, 0.03, and 0.02, respectively), while Combined differed significantly from Healthy only for the slow and medium cadence bands (p=0.01 and 0.03, respectively). There was no main effect for steps/day between groups (p=0.06, η²=0.1). CONCLUSION: Although there was no main effect of group for steps/day, several cadence-based metrics were lower among the FAIS groups, particularly for Cam vs Healthy. Future studies are encouraged to examine step-based metrics in individuals with FAIS, as they appear to capture real-world differences in walking behaviors