Clinicians often must select an appropriate prophylactic ankle support system for their patients from a variety of ankle orthoses and ankle taping configurations. The purpose of this study was to compare the effectiveness of the DonJoy Ankle Ligament Protector and a newly developed ankle taping procedure in restricting foot and ankle motion before and after exercise. Subjects were eight males and eight females who reported no history of ankle injury during the 6 months prior to testing, neurological condition, lower extremity arthritis, lower extremity fracture, or cardiac or balance problems. A Biodex dynamometer and computer were used to impose passive moments and to measure eversion and inversion prior to application of the ankle support systems, following application, and following 10 minutes of figure-of-eight running and 20 unilateral toe raises. Both ankles of each subject were assessed for each ankle support system. Subjects also compared the support systems for comfort, stability, and cosmetic acceptability. Both ankle support systems significantly reduced eversion and inversion following application and following exercise compared with preapplication measurements. Eversion measurements increased significantly following exercise for both ankle support systems compared with postapplication measurements. Inversion displacement following application was greater for the Ankle Ligament Protector than the ankle taping system. The two ankle support systems did not differ significantly following exercise for eversion or inversion measurements. The results may assist clinicians in selecting either of these ankle support systems for use in protection against ankle sprain injury.