Date of Award
M.S.E.S. in Exercise Science
John C. Garner
Dwight E. Waddell
Hazards and challenges present in the workplace pose a number of potential risks for injuries and illness. Nearly 3.1 million nonfatal workplace injuries and illness were reported in 2010 (BLS, 2010). The probability of falls has been related to balance decrements. Further, an important point of distinction is 45% of all falls have been attributed to inappropriate footwear (Menant et al. 2008) Previous studies have shown decrements in balance as a result of different footwear (Menant et al. 2008) and after an increased workload over a specific period of time (Yaggie & McGregor, 2002; Gribble & Hertel, 2004). Occupational footwear is often designed for safety and may fail to provide appropriate foot biomechanics. As such the functionality of occupational footwear may impact balance characteristics over time. The purpose of the study is to examine the differences in balance in while wearing different types of occupational footwear for extended durations. Fourteen healthy male adults (aged 23.6±1.2 years; height of 181±5.3 cm; weight of 89.2±14.6 kg), with no history of orthopedic, musculoskeletal, cardiovascular, neurological and vestibular abnormalities participated in this study. The experimental session included an extended duration of walking (4hours) with balance measured at 30min intervals (Pre, 30, 60, 90, 120, 150, 180, 210 & 240min). The standing balance protocol assessment was done on the six conditions of the Neurocom Equitest SOT (EO, EC, EOSRV, EOSRP, ECSRP and EOSRVP). The values of the dependent sway variables were derived from the Center of Pressure (CoP) movement. The average sway velocity (VEL) and the root-mean-square (RMS) of the CoP were used to characterize the postural sway in the anterior-posterior (APVEL & APRMS) and the medio-lateral (MLVEL & MLRMS) directions during the 60-second testing period. Participants were randomly assigned 3 different types of occupational footwear: Work Boots (WB) (mass 0.39±0.06 kg), Tactical Boots (TB) (mass 0.53±0.08 kg) and Low Top Boots (LT) (mass 0.89±0.05 kg) with a minimum of 72 hours of rest between conditions. Balance dependent variables were evaluated using a 3 x 9 (Footwear [WB v. TB v. LT]) x (Extended duration of walking intervals [Pre, 30, 60, 90, 120, 150, 180, 210 & 240] RMANOVA and independently for the six SOT balance conditions (EO, EC, EOSRV, EOSRP, ECSRP and EOSRVP) to identify any existing differences within the exposure time as well as the footwear types. Significant differences were found over time in the EO, EC, EOSRV & EOSRP for MLRMS and between footwear in the EC for APRMS and MLRMS and EOSRP for MLRMS. These results indicate a decrement in balance performance over time but the differences were limited to MLRMS. The decline in balance may be attributed to fatigue resulting from an extended duration of walking/standing. Significant differences were found between the WB, TB and LT, where the LT had a higher postural sway RMS. The use of LT resulted in a relatively greater balance decrement, especially when vision was absent and with conflicting somatosensory input. The WB and TB despite having a greater mass, had less balance decrement, which can be related to their elevated boot shaft height. Results from this data suggest that the high boot shaft supports the ankle, resulting in decreased fatigue, and thus better balance.
Chander, Harish, "Impacts on Balance When Walking in Occupational Footwear" (2012). Electronic Theses and Dissertations. 79.