Roughly 1/3 of adults older than 65 fall each year, resulting in more than 3 million emergency room visits, thousands of deaths, and over $50 Billion in direct costs. The Centers for Disease Control and Prevention (CDC) estimate that 1/3 of falls are preventable with effective mitigation strategies, particularly for imbalance. Therefore, quantification of imbalance is being studied extensively in recent years. In this study we investigate the feasibility of plantar pressure mapping in balance assessment through a healthy human subject study. We used an in-house plantar pressure mapping device with high precision based on Frustrated Total Internal Reflection to measure subjects sway during the Romberg test. Through the measurements obtained from all subjects, we measured the minimum spatial resolution required for plantar pressure mapping devices in assessment of balance. We conclude that most of the current devices in the market lack the requirements for imbalance measurements.