Maintaining postural stability is crucial, especially in hazardous occupational environments. The purpose of the study was to assess the role of three occupational footwear (low top shoe (LT); tactical work boot (TB) and steel-toed work boot (WB)) on postural stability when exposed to an occupational workload (4-h) involving standing/walking using the sensory organization test (SOT) equilibrium (EQ) scores and comparing current results with previously published postural sway variables from the same study. Fourteen male adults were tested on three separate days wearing a randomized occupational footwear, at the beginning (pre) and every 30 min of the 4-h workload until 240th min. SOT EQ scores were analyzed using a 3 × 9 repeated measures analysis of variance at an alpha level of 0.05. Significant differences between footwear was found in eyes open (p = 0.03) and eyes closed (p = 0.001) conditions. Pairwise comparisons revealed that LT had significantly lower postural stability compared to TB and WB. No other significant differences were found between footwear and over time. Significant differences between footwear can be attributed to design characteristics of footwear. Lack of significant differences over time suggests that, even though the average EQ scores decreased during the workload implying less postural stability, SOT EQ scores alone may not be sufficient to detect postural stability changes over the 4-h workload.

While design modifications present on work boots improve safety, they may not always provide optimal human performance during work tasks. Understanding the impact of these different design features on biomechanical and physiological postural control and locomotion variables can aid in better design modifications that can provide a safe and efficient human performance. This brief review focuses on a series of studies conducted by the current research team, that have tested three different work boots (SB: high-top steel-toed work boots; TB: high-top tactical work boots; SR: low-top slip-resistant work boots). The series of studies included testing of these work boots or combinations of them under acute and chronic simulated occupational workloads, assessing biomechanical variable such as postural stability, gait, slips, and muscle activity, as well as physiological variables such as heart rate, energy expenditure, oxygen consumption, and pain perception. The impact of each of the work boots and their design feature on postural control and locomotion are summarized from these studies’ previously published literature. Finally, work boot design suggestions for optimal human performance are provided for better work boot selection, modification, and design.

Decrements to postural control manifest as an increase in muscle activity, indicating continuous attempts to maintain body equilibrium and postural stability. Extrinsic factors such as footwear, and intrinsic factors such as muscle fatigue, can affect postural stability. The purpose of this study was to analyze the impact of two types of military footwear and a military-type load-carrying task on lower extremity muscle activity during various postural stability tasks. Sixteen males’ (age: 26.63 ± 3.93 years; mass: 87 ± 12.4 kg; height: 178.04 ± 6.2 cm) muscle activity from knee flexors, extensors, ankle dorsiflexors, and plantar flexors were measured using electromyography in standard (STD) and minimalist (MIN) military footwear, before (PRE) and after (POST) a simulated workload during sensory organization and motor control tests on the Neurocom EquitestTM. Mean muscle activity was analyzed using 2 (footwear) × 2 (time) repeated measures ANOVA with an alpha level of 0.05. Results revealed a requirement of significantly greater muscle activity in POST and STD. MIN demonstrated lesser balance decrements POST workload, which could be attributed to its design characteristics. Results will help in suggesting footwear design characteristics to minimize muscular exertion while eliciting better postural control, and to prevent postural instability due to overexertion in military personnel.

Background: Postural strategies such as ankle, hip, or combined ankle-hip strategies are used to maintain optimal postural stability, which can be influenced by the footwear type and physiological workload. Purpose: This paper reports previously unreported postural strategy scores during the six conditions of the sensory organization test (SOT). Methods: Fourteen healthy males (age: 23.6 ± 1.2 years; height: 181 ± 5.3 cm; mass: 89.2 ± 14.6 kg) were tested for postural strategy adopted during SOT in three types of occupational footwear (steel-toed work boot, tactical work boot, low-top work shoe) every 30 min during a 4-h simulated occupational workload. Postural strategy scores were analyzed using repeated measures analysis of variance at 0.05 alpha level. Results: Significant differences among postural strategy scores were only evident between SOT conditions, and but not between footwear type or the workload. Conclusions: Findings indicate that occupational footwear and occupational workload did not cause a significant change in reliance on postural strategies. The significant changes in postural strategy scores were due to the availability of accurate and/or conflicting sensory feedback during SOT conditions. In SOT conditions where all three types of sensory feedback was available, the ankle strategy was predominantly adopted, while more reliance on hip strategy occurred in conditions with absent or conflicting sensory feedback.

Background of Study: Females generally have a 6-8 times higher risk for lower extremity injury compared to male counterparts due to biomechanical differences and/or poor landing strategies. In recent years, a great deal of focus has been placed on prevention and reduction of non-contact lower extremity injuries. This has spurred the development of assessment methods to determine how athletes move and tools with which those motions are measured. Efforts have been made to measure and quantify movement strategies, which have given rise to multiple movement tests and measurement devices. One approach is the use of wearable technologies used in conjunction with a movement screening. Objective: Demonstrate a practical approach of using wearable technologies to guide training regimens in a population of female athletes that would be considered at risk for lower extremity injuries. Methods: A cohort of Division I female volleyball athletes were screened using wearable technology then assigned an intervention based on screening results. Comparisons were made between injury rates during the season when the intervention was applied compared to previous seasons. Results: All lower extremity injury rates were reduced after the intervention was applied. Conclusions: The use of wearable technology aids in quantifying movement to then assign a strategic intervention to reduce injuries in an at risk athletic population.

Muscle activity from the slipping leg have been previously used to analyze slip induced falls. However, the impact of casual alternative footwear on slipping leg muscle activity when exposed to slippery environments is still unknown. The purpose of the study was to analyze the impact of alternative footwear (crocs (CC) and flip-flops (FF)) compared to slip-resistant footwear (LT) on lower extremity muscle activity when exposed to dry gait (NG), unexpected (US), alert (AS), and expected slips (ES). Eighteen healthy males (age: 22.3 ± 2.2 years; height: 177.7 ± 6.9 cm; weight: 79.3 ± 7.6 kg) completed the study in a repeated measures design in three footwear sessions separated by 48 h. Electromyography (EMG) muscle activity from four muscles of the lead/slipping leg was measured during the stance phase of the gait-slip trials. A 3 (footwear) × 4 (gait-slip trials) repeated measures analysis of variance was used to analyze EMG dependent variables mean, peak, and percent of maximal voluntary contraction. Greater lower extremity muscle activation during the stance phase was seen in US and AS conditions compared to NG and ES. In addition, footwear differences were seen for the alternative footwear (CC and FF) during US and AS, while the low top slip resistant shoe had no differences across all gait trials, suggesting it as the most efficient footwear of choice, especially when maneuvering slippery flooring conditions, either with or without the knowledge of an impending slip.