An explorative qualitative study to determine the footwear needs of workers in standing environments

The nature of work related tasks and the design of many work places, makes standing the primary occupational posture. At least 50% of the employed population are exposed to the risks associated with prolonged standing [1, 2]. Prolonged standing, defined as standing for 50% or more of the working day [3], is associated with multiple health issues including chronic venous insufficiency, preterm birth, carotid atherosclerosis and work related musculoskeletal disorders [4]. The standing work places discussed in this paper include those that are predominantly standing with minimal ambulation.

Back and lower limb musculoskeletal disorders (MSD) are particularly prevalent with risk of low back and lower extremity/ foot pain being increased 1.9 and 1.7 fold respectively in those who stand for at least half their time at work [5]. Nealy et al. [6] reported that approximately 50% of nurses suffer MSD of the foot, substantially more than the 17.4% in the general population [7]. Similarly in perioperative staff, 43% reported pain in their leg or feet, compared to 12% in the general population [8]. The majority of staff (91%) attributed the pain to their work. For the employer, MSD can be costly in terms of absence and decreased efficiency [4].

As footwear provides the only interface between the body and ground when standing, alterations in footwear have the ability to influence the forces acting through the body, posture and movement [9], as well as to provide necessary protection against foot trauma and slips. Indeed, differences in footwear designs have been shown to affect fatigue and discomfort [10, 11], muscle activation and pressure under the foot [12, 13] all of which are factors relating to MSD. Therefore, wearing the correct footwear at work has the potential to reduce the risk of MSD and acute trauma.

A recent review paper highlighted that despite the detrimental impact of prolonged standing on the body, there is a scarcity of information relating to potential solutions, particularly in terms of flooring and footwear [8]. To ensure that workers wear the most suitable footwear, it is necessary to design and develop products based on both the physical environmental constraints and the personal preference of the workers. The limited research into the requirements of footwear from a workers perspective, particularly in relation to musculoskeletal symptoms, comfort, and design provides a starting point for understanding footwear in the workplace. By better understanding the footwear needs of workers, manufacturers may be able to produce footwear that will meet the requirements of the people who wear them and the environments they are worn in. For employers, this understanding can ensure the most appropriate footwear is identified, thus meeting their duty of care and reducing the likelihood of civil action from employees. Consequently, this study aims for the first time to explore workers needs for footwear in the ‘standing’ workplace in relation to MSD, symptoms, comfort and design.

Following ethical approval (University of Salford), participants were recruited through purposive sampling in relation to two occupations where standing is predominant and environments ‘challenging’ (when compared to office workers for example). The recruitment criteria was workers who work in demanding environments that require standing for the majority of the day. Multiple kitchens and veterinary hospitals were approached and within those that agreed to participate (3 kitchens, 1 veterinary hospital) staff volunteered if they wanted to take part after reading the participant information sheet. A total of 14 participants were included (kitchen staff: 8 (male: 6, female: 2), veterinary hospital theatre staff: 6 (male: 2, female: 4)). The number of participants is similar to that seen in other studies focusing on in-depth perceptions of footwear on specific conditions [14‐16]. Participants provided informed consent and data collection (semi-structured, individual interviews) took place at their place of work by the researcher (JA). The interview was recorded digitally with supplementary field notes.

The participant’s job role, weekly working hours, time in job and type of shoes worn were recorded. The questions were non-specific to allow participants to talk about what was most relevant to them, but included their experiences and ideas of good/bad footwear features. Prompts were given during the interview where necessary. A list of questions and prompts can be seen (Table 1).

The words that are regularly used to describe work footwear from a manufacturer’s point of view such as ‘comfortable’, ‘supportive’ and ‘cushioned’ were explored with each participant in relation to meaning and importance.

All interviews were transcribed verbatim by the researcher (JA). Thematic analysis was conducted in line with that described by Attride-Stirling [17]. The results were reviewed by a second researcher (AW) in order to confirm and agree meaning and interpretation.

Participant’s information was recorded at the beginning of the interview (Table 2). Basic and organising themes were grouped into a global theme of ‘footwear needs’ shown in Fig. 1. Table 3 displays the number of individuals that discussed each issue.

Chefs worked an average of 50 ± 8 h a week and time in work ranged from 1 to 17 years (average = 7 years). Veterinary hospital staff worked on average 40 ± 6 h per week and time in work ranged from 3 to 37 years (average = 17 years). Both environments consisted of hard flooring throughout. The chefs prepared, cooked and presented food predominantly around kitchen counters/ cookers. Veterinary workers were based standing around operating tables during surgery but also undertook inpatient care and cleaning. In both environments, tasks varied based on individual roles. All individuals purchased their own footwear.

This is the first study to provide a unique insight into the footwear needs of workers in prolonged standing environments from a qualitative perspective. The footwear needs of vets and chefs can be broken into three key themes: sensations and symptoms of the worker; the function and suitability of the shoe for the environment and factors that influence footwear choice. Creating footwear that workers will adhere to wearing with the correct safety features and ergonomic design is a possible mechanism for injury prevention as it could improve safety [18] and reduce MSD [12, 19, 20]. Therefore this research has important implications for footwear design and manufacturing.

There was a high proportion of work related MSD reported (93%) that workers associated with the long hours on their feet. In agreement to previous studies that also found high rates of MSD in jobs requiring prolonged standing, the main areas affected were the back and lower extremities [5, 21, 22]. MSD were described as being obscured by occupational demands and participants identified a need to work through these aches and pains. This could cause conditions to develop and worsen as the summation of wear and tear from prolonged standing over time can result in chronic issues such as joint degeneration and chronic venous disease [4, 8, 23]. Furthermore, the reluctance to mention MSD in the workplace and the perception that they were an expected part of the job could reduce the chance of professional help being sought. Workers were affected both during and after work as well as the day following a long shift, signifying that quality of life outside of work could also be impacted.

Despite some beliefs that MSD are independent of the footwear worn, research indicates there is some potential to reduce aches, pains and feelings of fatigue through alterations in footwear or orthotic design [12, 19, 20, 24]. However, nothing specific to work place enviroments has been produced thus far. A few indications were made to the importance of footbed shape by relating flat footwear to an increase in pain and demonstrating a preference towards arch support. The literature supports this as a medial arch support increases the contact area and redistributes the plantar pressure of the foot [12]. However, due to the mix of beliefs regarding the link between MSD and footwear, educating workers on how different shoe features may impact on specific complaints could be required to avoid poor footwear choices, and this could include when to seek help from a health professional.

The work environments necessitate distinct footwear requirements. The specific flooring in both environments and high level of fluids result in a need for slip resistance. This was identified by almost all of the participants in this study as being of primary importance and has been demonstrated in previous studies to reduce slip rates by more than 50% [18]. Despite some misgivings about suitability of the slip properties of their current shoes, many participants still wore the footwear they deemed unsuitable. Due to the strong link between subjective and objective measures of friction [25], it is expected that use of a shoe that is perceived to have inadequate slip resistance would be detrimental to safety. Problems with the durability of the footwear grip was identified, and therefore it can be recommended that manufacturers should work to improve this or educate as to when footwear should be replaced. This is important for both safety and to align with criteria concerning generalised ‘durability’ and value of the footwear. Footwear that incorporated a method to identify when slip resistance reached an unsafe level could promote safety.

Heat is also an environmental concern for both vets and chefs. High temperatures were associated with hot, sweaty and odorous feet. High temperatures cause feet to sweat, creating a humid microclimate in the shoe, which results in discomfort [26] and exacerbates frictional forces that cause blisters [27]. Furthermore, sweat causes the surface of the skin to become more alkaline, promoting the development of pathogenic bacteria and fungi. As a solution to the discomfort, workers in both environments reported removing their feet from the footwear in order to cool them down, consequently exposing the foot to hazards. Therefore, it is clear that manufacturers must develop methods to maintain cooler in-shoe climates to improve comfort and reduce the risk of foot conditions developing.

The design of the shoe also influences the temperature, with an open back identified as much preferred due to the circulation of air it allows alongside the ease of donning/doffing the shoes. However, an open back and ventilation holes were unfavourable when the environment became wet. It is not always possible to create a perfect shoe for all environments and therefore features must be prioritised, or customised [28]. For these environments, allowing air into the shoe was the primary issue and therefore we would recommend prioritising the open backed shoe. However, feelings of being unsafe were promoted from shoes that did not remain on the foot. If the shoe did not hold the foot, workers had to resort to physical methods to hold the shoe on. Curling the toes whilst walking, a mechanism that is also adopted when wearing flip flops [29, 30], was used to hold the shoe in place. This could alter the way in which workers move as well as how the muscles are activating consequently impacting injury risk. A strap on an open backed shoe could improve the stability of the shoe on the foot whilst maintaining breathability.

Fit was an important footwear characteristic that was mentioned in its own right as well as in relation to comfort, donning and doffing of shoes and footwear individualisation. A good fitting shoe was given as a reason for not changing footwear, demonstrating its overall importance to footwear comfort and choice. Previously, it has been shown that fit is an important influencer of comfort, with other factors only influencing comfort when the fit was correct [31]. In particular, it was suggested that people with wide or narrow feet had issues purchasing good fitting footwear and there was a need for half sizes to improve the fit. Manufacturers can also play a role in guiding individuals to the correct size footwear, be it through online technology or in retail shops.

Initial and lasting comfort are both essential in work footwear. There is a similar high priority of footwear comfort for mail delivery, construction and care home workers with some workers choosing comfortable footwear over that with the correct safety features [28]. Comfort is related to the footwear, the task or activity and the characteristics of the individual worker such as skeletal alignment [32‐35]. This highlights a potential requirement of different footwear for different occupations and reinforces that one shoe will not fit all. Comfort had positive associations with support, cushioning and the idea of footwear individualisation. Individualisation of the footwear or footbed shape was proposed to improve comfort and reduce injury. The literature reinforces that footwear customisation can enhance fit, comfort and prevent injury [36]. Whilst mass customisation would be extremely costly, there could be the option of using a best-matched fit method in which several options are made available and the individual worker chooses the most suitable. This could either be done for the whole shoe or just the footbed or insole and could be a cost-effective way to enhance comfort, meet customer desires [37] and perhaps reduce MSD.

There are a number of factors that can also influence footwear choice. It must be easy to clean and therefore have no fastening on the top that dirt can stick to. There is also a reluctance to spend money on work shoes and indeed it has previously been highlighted that leisure footwear is given higher financial priority than work footwear [28]. This study identified a price-quality trade off in which more money would be spent on a product if it was durable and of high quality. The perception of the factors involved in this trade off could be fundamental in terms of communicating the features of footwear, its benefits, and how this value proposition is proportional to price. Style is a secondary concern to the shoe function and comfort. This differentiates the needs of work footwear from that of leisure wear, where it has been suggested that style is preferential to comfort [38] and provides manufacturers an element of leeway in the shoe design. Chefs were more concerned with shoe appearance than vets, with mention of desirable brands. In these environments, general protocol dictates white or black shoes. It is also worth noting that the visual appearance of the shoe conveys perceptions about the shoe, including that relating to its function, performance and ergonomic quality, which could affect the purchase of the product [39, 40]. In this manner, footwear can be designed to match the consumers perceived needs and thus increase the chance of a worker choosing the shoe.

User preferences for work footwear and concerns regarding work related MSD have been largely ignored and this is the first study that we are aware of that focuses on user preferences for footwear in prolonged standing environments. Therefore this research is novel and provides a starting point from which the wider issues can be investigated. The use of open questions allowed identification of topic areas that were important to the participants. Using a small study sample of 14 participants decreases the generalisability of the results although this was not the aim of the study and the study aim of gaining an in-depth understanding from a few was met. Further, respondent bias could result from the self-volunteering nature of participant selection. The outcome that some preferences are work environment specific means that other environments might require separate investigation. The mixed group of participants from different environments in this study could also be a limitation, although they both met the purposive sampling criteria of standing for prolonged periods. In the future, a larger study could be used to investigate any differences between the two groups and to quantify any relationship between footwear and MSD..

When designing the ideal work footwear for standing environments, the functionality of the shoe for the environment must be addressed, the sensations and symptoms of the workers taken into account to encourage adherence and the decision influencers should be met to encourage initial footwear choice. If any of these criteria are not met, workers are forced to choose based on favoured criteria, which can result in a decrease in safety features, comfort or both and could potentially lead to MSD or injury. Health professionals should take this into account when prescribing footwear or orthotics and footwear manufacturers must aim to meet all criteria. Future research is necessary to understand the link between footwear choice, work demands and MSD. The correct footwear and education regarding foot health and footwear choice could improve working conditions for workers and perhaps impact the high number of MSD repeatedly recorded in jobs that require prolonged periods of standing.