Effects of balance-enhancing footwear on postural sway when standing and walking in older women

Administration of the intervention and all testing procedures will be performed in the Foot and Ankle Laboratory at La Trobe University, Bundoora, Victoria, Australia. The intervention is a pair of footwear and insoles designed to improve balance. 1. Footwear The footwear incorporates features previously shown to be beneficial for balance. Specifically, it has a firm (Shore A hardness 55) rubber sole of 25 mm thickness under the heel and 18 mm under the forefoot, laces plus Velcro® fastening, a high collar to support the ankle, and a firm heel counter. The outersole has been modified to optimise slip resistance by grinding a 10 degree bevel into the heel region, placing grooves perpendicular to the sole (1.2 mm deep and 2.4 mm wide) across the heel surface area, and placing perpendicular grooves (5 mm deep and 12 mm wide) across the rest of the sole. 2. Insoles The footwear incorporates a textured insole, constructed from 4 mm thick ethyl vinyl acetate (Shore A 25 ) with dome-shaped projections (3 mm high and 8 mm diameter, Shore A 85 ) placed across the forefoot in a 15 mm diamond pattern and along the lateral border, extending to the heel. The design of the textured insole was informed by previous studies reporting improvements on balance in older people when similar insoles were worn. A research assistant with a podiatry degree and current registration will fit the footwear/insoles to each participant using a Brannock device. The prototype footwear and the comparator condition (see next item) will be worn for a single assessment session. All participants will be tested in both footwear conditions, with the order of testing randomised. The testing session will take a total of approximately 40 minutes, as described below: 1. Prototype footwear/insoles fitted and acclimatisation period (5 mins). 2. Sensor fitted. Standing balance tests (30 seconds each test - total approximately 5 mins). 3. Treadmill walking test (2 minutes continual walking). 4. Rest/wash-out period, sensor removed (10 mins). 5. Comparator footwear fitted and acclimatisation period (5 mins). 6. Sensor fitted. Standing balance tests (30 seconds each test - total approximately 5 mins). 7. Treadmill walking test (2 minutes continual walking).