The role of supervisor work-life support on the correlation between work autonomy, workload and performance: perspective from Tanzania banking employees

This research aims to assess the influence of supervisor work-life support on bank employees' performance linking work autonomy and employee workload in this relationship. A survey was conducted among bank employees in the Central Zone regions of Tanzania. Bank workers completed 417 survey questionnaires in total. The data was then analysed using structural equation modelling. The researchers use Smart PLS, a data analysis tool, to see if there are any theoretically supported connections between variables of interest. SPSS, on the other hand, handled data coding and descriptive statistics. The study results revealed that work autonomy mediated significantly the association among supervisor work-life support and work performance. Contrary to expectation, the linking of workload in the correlation between supervisor work-life support and work performance was negative and insignificant. Moreover, work autonomy and workload significantly influence bank employees’ job performance in this study. Similarly, the study findings indicated that supervisor work-life support positively impacts employee performance. The study has important implications for managers since it improves understanding of the strengths of their organizations' work-life practices. Such as workload and work autonomy when linked with supervisor work-life support on influencing employee job performance and developing new strategies that may enhance employee's well-being. Again, the findings imply that there should be supportive work-life practices that moderate the balance between home and work realms to attain effective organizational performance.


Introduction
Changes and the conflicts between the various roles that individuals perform necessitate organizations to continually be forced to offer and implement different work-life practices to promote the efforts of workers to meet their employment, family, and personal-related obligations [1]. Organizational work-life/family support modifies human resource management policies, practices, as well as job structures to increase flexibility and provide employees greater discretion over where, when, and how much work they perform [2]. Supervisor work-life support (SWLS) primarily "provides additional instrumental resources, such as knowledge and direct services, to enable employees to combine work with caring for family members or other vital nonwork activities" [3]. It is believed that employees can better manage their job duties and family expectations with the assistance of a supervisor in balancing work and life demands. In terms of incentives to work and well-being, highly efficient businesses foster performance quality and employee flourishing. This study investigates whether or not the linking supervisor

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Future Business Journal *Correspondence: shafiimwana@gmail.com; shafiimwanaidi@yahoo.com work-life support will influence the association between work autonomy, workload, and employees' job performance in the banking sector.
Supervisor work-life support is some management behaviours that enhance employee autonomy, including respecting employees' viewpoints, offering alternatives, providing relevant feedback, promoting initiating, making assignments optimally demanding, and distributing resources [4]. Employees who believe their supervisors are supportive have more satisfied with job, perform better, and are well committed to the company. Burnout syndrome, work stress, and the intention to quit are more likely to occur in an organization where supervisor work-life support is low, which can have adverse consequences on the organization's labour force [5]. Likewise, work autonomy results in a crucial psychological state in which experienced accountability for the task's outcomes leads to improved work performance and internal job motivation. That is, autonomy is vital in escalating employee performance and job satisfaction and alleviating job stress, frustration, and anxiety among employees [6]. Work autonomy is "the level of freedom and discretion granted to individual employees to carry out their work tasks" [7]. According to empirical studies, workplace autonomy support from supervisors or managers can result in various excellent job outcomes, including general creativity and job performance [4,8].
On the other hand, the high workload can impact negatively employee job performance by successfully exhausting time and energy (resources) needed to complete job responsibilities [9]. Employee workload is a term that relates to the amount of time spent on specific tasks. It can also be regarded as the number of tasks that has been assigned to a worker in a given time [10], which requires the employee to devote his energy and time to execute it.
Tanzania made low progress in the area of decent hours. Most Tanzanians continue to work excessive hours of more than 48 h per week [11]. Accordingly, bank employees in Tanzania work incredibly long hours based on this study results, defined as above 50 h per week as well as more than 9 h per day, which is higher than the 48 h as stipulated by ILO, Convention, 1930 (No. 30) [12]. The Convention restricts the working hours of those subject to it to 48 h per week and eight hours per day [13]. The ILO convention (No. 156), approved in 1981, insists that it is vital for organizations of all type to assist workers to achieve a healthy balance between job and family (life) obligations [14]. In recent years, the bank sector in Africa has also gained a reputation for having an insufficient work-life balance, excessive working hours, weekend work, and a very stressful and inflexible working atmosphere [15].
Thus, supervisor work-life support at work, in this case, is vital to encourage employees by providing autonomy to fulfil the job and nonwork commitments and duties, hence lessening their heavy workload. Again, SWLS may increase employee job performance since employees who see that their supervisors are supportive are more likely to be content with their work environment.
Although there is previous research examined supervisor support with work autonomy and or with workload focused on workplace outcomes and employee's well-being, e.g. mental health [7], turnover intention [16], on job satisfaction [10,17], and emotional exhaustion [18]. None of these studies assessed the influence of supervisor work-life support on workload, work autonomy (as mediators) and job performance. In addition, further examination of previously published studies reveals conflicting findings in terms of the consequences of workload on job performance [19][20][21][22]. The empirical research relevant to the association between work autonomy and performance is also inconclusive in its conclusions [22,23]. Inconsistent results regarding the correlation among work autonomy, workload, and employees' performance may have been partly caused by direct relationship assessment only. Having come to this realization, the current study, in contrast to a dearth of previous and recent studies, investigates the role of supervisor work-family/life support on workload and work autonomy as mediators and employee job performance. Thus, our study addresses the need to prove this ambiguous relationship and tests the impact of supervisor work-life support on these relationships, extending this research stream to other societies and potentially contributing to richer insights into the supportive workplace in the bank setting.
However, several studies have investigated work autonomy and workload in different fields. To the best of researchers' knowledge, this is the new study to assess the mediating role of workload and work autonomy in the correlation between supervisor work-life support and employees' performance. This research aims to fill this gap in prior banking sector research by concentrating on the correlations between these constructs. This study will help managers and businesses understand the importance of supervisor work-life support on subordinates' work flexibility and reasonable workload on performance, thus improving the work environment by altering job design and workload management. This study's structure comprises an introduction, literature review as well as the formation of hypotheses, Methodology, Results, Discussion, and study implications, and conclusion and study limitations.

Theoretical perspectives
In the course of our research, we constructed and validated a research model that is grounded on the "job demand-resource (JD-R) model" [24] as well as "Conservation of Resource (COR) theory" [25] to describe how supervisors work-life support linked with work autonomy and workload are resourceful on influencing employees' job performance. The JD-R includes two theoretical concepts: job demands (workload) as well as job resources such as social support (supervisor support) as well as job autonomy [26]. By investing in emotional resources acquired from supervisors through reshaping the work place condition for higher support resources and lower to moderate demands, human resource practitioners will be able to improve employees' work-family balance and performance, which is a crucial role in the current model. Through two mediating mechanisms: health impairment and motivation, JD-R affects employees' welfare or performance outcomes. According to the JD-R model, high workloads drain workers' mental as well as physical resources, which results in health problems, low job satisfaction, and less performance [27]. Workplace resources (supervisor support) boost employees' mental and physical energies during the motivating process, resulting in higher job engagement, satisfaction, and performance [28].
Also, according to the COR, time is the most finite and tangible resource; an hour committed to the job domain means an hour not accessible for other life spheres, diminishing the ability of people to meet personal and family needs. Studies have linked long working hours to WFC and lower life satisfaction [18]. In Tanzania banks, employees experience long working hours and an inflexible workplace, as explained earlier. It is assumed that excessive workload can reduce existing resources by draining emotional and physical energies or taking much of one's time, or preventing a person from gaining new resources [9]. Hobfoll [25] mentioned that resources are personal kills, objects, energies, time, and money treasured by the individual.

Supervisor work-life support and employee job performance
Employee belief that their managers care about their well-being, respect their work, and are generally helpful is defined as supervisor support [29]. Mas-machuca [30] asserted that supervisor support in work-family/life is a representation of an employee's impression of whether their supervisor is sympathetic to their nonwork interests. Similarly, we can refer to supervisor work-life support behaviour as the level to which employees trust that their superior is concern about their work and personal life demands (employee well-being) and hence assist them in achieving a healthy work-life balance. Work, life, and family support from supervisors can take many forms, including consideration of employees' families and other personal commitments, demonstration of respect, understanding, sympathy, and sensitivity regarding family responsibilities, and the facilitation of employees' feelings of ease when discussing challenges pertaining to their families [31]. In that case, effective supervision is regarded as a developmental and persuasive resource in organizational contexts. Supervisors are well-versed in a wide range of knowledge and are acutely aware of the demands of their subordinates [32]. More importantly, the supervisor fosters value congruence for both employees and supervisors and plays a critical role in maximizing employees' organizational outcomes [33,34]. Supervisors have the ability to function as a link between a business and its staff members, and the acts they do can dramatically affect how workers perceive the workfamily balance policy of their employer [27]. As a result, it affects employees' attitudes about work, which in turn impacts their performance. Supervisory support in previous studies indicate that is positively with job outcomes, e.g. job satisfaction and innovative behaviour [35], reduced turnover intention [36] and increased employee performance [5, 32,37]. Also, a study by [27] on the association among employees' supportive supervisor and performance via work-life balance reported a positive correlation among the variables. When an employee considers his or her supervisor to be sympathetic, cooperative and encouraging on matters of work-life balance, the person will attempt to reciprocate by contributing via his or her performance and by meeting the supervisor's goals [32,38,39]. Employees feel heard, respected, and cared for when they have strong supervisory support in work and life issues. Supportive bosses recognize their subordinates' relationships and a positive work environment. Employees who have confidence in their supervisors support them are more likely to be encouraged, contributing to a more favourable work environment. As a result, individuals may improve their work performance by more successfully committing to the firm [5,40]. Employees who consider their bosses supportive report job satisfaction and performance [41]. In this scenario, we believe that when employees manage to maintain a good balance between their personal and professional responsibilities, they will respond by being committed to the organization. Therefore, this study contends that SWLS contributes to increased employee job performance.
H 1 Supervisor work-family/life support influence employee job performance.

Supervisor work-family/life support and work autonomy
Supervisor support for employee work autonomy refers to a "supervisor's capacity to comprehend and appreciate their subordinates' viewpoints, allow choice where available, provide relevant rationale when the choice is limited, encourage self-initiation, and relieve pressure" [4]. The Job Demand resource (JD-R) Model regards supervisor support a job resource assisting employees in achieving a healthy work-life [27]. That supervisor, as a resource, supports work autonomy by granting employees the freedom to schedule their work, make work-related decisions, and choose different work methods, provided they concentrate on meeting organizational objectives. Job autonomy can be regarded as a human resource practice, as well as supervisors can play a significant role in granting job autonomy to their subordinates. It is easy for subordinates to believe that their superior appreciates their contributions and is concerned about their well-being when they receive such valuable resources as autonomy [38].
To put it another way, when employees see their bosses are offering them valuable resources (job autonomy), they will interpret that they are supportive. In particular, subordinates may take this voluntary activity as a sign that their superior is supportive when a supervisor offers them job autonomy. Supervisors that have a high level of job autonomy are in a good position to provide additional resources for their staff, because autonomy influences their decision making capacity [42]. Mcguire [43] revealed that supervisors with sufficient autonomy may provide a conducive work environment to subordinates injured at work more than supervisors with limited autonomy. Hence, we propose that; H 2 Supervisor work-life support behaviour influences employee work autonomy.

Work autonomy and employee job performance
Work autonomy is can be described as the "degree to which work gives a person significant freedom, independence, and flexibility in scheduling work and selecting how it will be completed" [29,44]. Similarly, work autonomy refers to the amount to which employees may choose when, where, and how they do their duties [18]. Therefore, we can refer to job autonomy as how much workers believe they have flexibility in making job-related decisions, implying that the organization values their input and ability to make good decisions. Work autonomy is a multifaceted concept that includes three key elements: work methods, scheduling, and decision-making [34]. Theory (SDT) state that "creating a work environment where employees are inspired in their autonomy is not only a good goal in itself, but it also leads to increased employee satisfaction and thriving, as well as other organizational benefits such as increased work performance (productivity)" [45]. Beenen [46] explain further that self-determination is the initiation and regulation of purposeful activity along with an intrinsic-extrinsic spectrum. SD theory further posits that the level of motivation that employees have for their work has an impact on both their performance and their well-being. STD motivation is a strong predictor of a wide range of psychological outcomes, including intrinsic motivation, self-esteem, and general well-being; cognitive outcomes, including creativity and learning; and behavioural outcomes, including job performance, job satisfaction, engagement, and lower burnout [46]. Employees' motivation is improved, and turnover is reduced when they have the freedom to choose their work schedule for completing specified tasks. Providing employees with the power to influence decision-making could improve job efficiency, effectiveness, and satisfaction.
According to previous research, more significant work autonomy contributes to being respected and trusted and a sense of pride in achieving organizational outcomes that reflect their decision-making talents. Work autonomy is among the several core job design features [22,47]. Equally important, they opined that autonomy leads to a vital psychological state in which professional accountability for the task outcomes leads to increased job performance and higher internal motivation. This factor is positioned to result in a more motivated and effective job. Job satisfaction, performance at work, responsibility, intrinsic motivation, and workplace involvement have all been positively correlated with autonomy [48,49]. Research on work autonomy has demonstrated a positive correlation among job autonomy and performance [22,48]. That autonomy increases motivation and works efficiency.
Autonomy replicates the degree to which a job requires an individual's self-determination, the right to arrange work or make decisions. Employee autonomy has a beneficial impact on the morale and efficiency of the workers. Generally, it is evidenced that this motivational impact of work autonomy is widely accepted, and it is an underlying premise in other research related to autonomy. Autonomy can be vital in escalating employee job satisfaction and, in turn, increasing job performance among bank employees. Thus, we hypothesize as follows; H 3 Work Autonomy influences bank Employees' job Performance.

Supervisor work-life support, work autonomy, and job performance
Supervisor work-life support (SWLS) primarily provides additional instrumental resources, e.g. knowledge as well as direct services, to assist employees to combine work with caring for family members or other vital nonwork activities [3, 50] and hence improved performance. As a result, supervisory support is widely considered a precondition for organizational support. Organizational Support Theory (OST) defines Supervisor Support (as organization's agent) as the extent to which workers believe their organization recognize their contributions and is concerned about employees' well-being [34,51]. In terms of performance, supervisor support on employees' autonomy is anticipated to improve and maintain their performance over time. The OST also states that when a company supports its employees, they feel obligated to help them reach their goals and objectives, and a supervisor is a crucial part of that support. A supportive supervisor believes in the subordinate's talents and may convey this belief through vocal expressions of trust, appreciation, and faith. In this method, the supervisor can persuade the staff that they can achieve the set objectives by supporting work autonomy and thus, lead to improved performance [34,52]. A person's high level of autonomy as well as support will have the ability to make use of his psychological resources such as cognitive, which will, in turn, enable the person to generate ideas that are both original and beneficial to the individual as organization performance. Employees believe that accomplishing their responsibilities is advantageous to their self-selected goals when supervisors support their autonomy because they like the working process and value the outcome of the activity [38]. The authors discovered that work autonomy is linked to participatory management methods, individual values, and supervisors' interpersonal orientation, all of which influence the degree of support for subordinates' autonomy [53].
A previous study found that employees feel driven and answerable for their behaviour, respond favourably to work, and attain better job outcomes when they believe their supervisors supporting work autonomy [54]. However, the study by [34] revealed that supervisor support does not directly influence employee performance, which necessitates further investigation. As a result, we posit that supervisor work-life support behaviour, such as granting employee work autonomy, aids the underlying motivational mechanism that guides as well as energizes workers, resulting in various positive related work outcomes, specifically improved performance. Therefore, we hypothesize that; H 4 Work autonomy mediates the association between Supervisor work-family/life support and performance.

Supervisor work-life support and workload
According to COR theory, workload reflects unfavourable working situations that contribute to resource reduction and emotional tiredness [55,56]. COR theory states that fears to resource loss come in the form of role demands represented in excessive workload. On top of that, the theory further assumes that job resources such as supervisor support can lessen employee stress associated with a high workload. We propose that work-life support supervisor, defined "as the belief that one's manager or supervisor value one's work-life issues" [57], influences employees' workload by providing emotional support.
Employees who receive more emotional instrumental support from their work supervisors in coping with life and family concerns can less prone to experience job interfering with their personal lives and causing them to feel burdened, even when the workload is high [2,58]. Workers perceive supervisory support as an indication that their bosses care about their happiness and their needs, thus decreasing the resource depletion caused by work-family conflict and job demands (workload) [59]. As mentioned earlier, job Demand Resource (JD-R) regards supervisor support as a valuable work resource that assists employees in managing work and life concerns. In that scenario, we believe that work/life-supportive supervisors are a crucial resource that assist employees in coping with the effects of high workloads, especially given that supervisors are directly accountable for their employees' workloads. Thus, the supervisor may act as a job resource [60] who assists employees in reaching a higher performance rate. Again, supervisor support can be regarded as the perception of a supervisor's value for subordinates' contributions and overseeing their well-being, such as shielding subordinates from heavy workloads [34]. Likewise, it is assumed that social support from supervisors will substantially impact workload. Supervisor work-family resources are believed to support stress resistance. They have good impacts on employees since they are frequently implemented in response to employees' wants and values as well as fit under Hobfoll definition of resources [61]. Therefore, explains why performance and attitudes are directly correlated with organizational work-family resources.
H 5 Supervisor work-family/life support has impact on employee workload.

Workload and employee job performance
Employee workload may be the number of tasks allocated to or required from a worker over a given period. Thus, workload applies to all tasks concerning the time workers spend executing professional duties, obligations, and interests at work [10,62]. The workload is also referred to as "a form of danger to resource loss that concerns time-related demands believed by employees to describe their occupations, such as the sense of having too many things to do within a limited time" [63]. The COR theory predicts that employees' well-being will be jeopardized anytime they are threatened with a prospective loss of resources, suffers an actual loss of resources, or fail to acquire new resources after investing existing resources.
Employee workload is a critical factor in employee efficiency and turnover. Suppose their workload is below the normal workload. In that case, it will invoke laziness and allow employees to be idle and engage in unproductive practices such as community politics, with its consequent performance implications. Accordingly, when the workload is greater than the normal workload, which is termed role/work overload. As a result, the employee may become overwhelmed. In turn, this will result in threats such as exhaustion and resulting breakdowns, ill feelings, frustration, and eventually cause them to leave the job [16].
Role overload arises when a person is faced with too many tasks within the available time. Work overload can lead to increased job dissatisfaction, increased production, decreased performance quality, and feelings of anxiety, rage, and personal failure [28,64]. According to COR theory [65] and JD-R, as explained earlier [66], we suggest that workload is a job demand that indicates consumption of time, energy, and psychological resources based on this paradigm. An increase in such demands necessitates using extra resources in the work environment. Because of the limited resources an employee has (time and energy), fewer resources will be available to meet other life demands [57]. A high workload depletes resources, which has an impact on employee role/job performance. Recently, employees are becoming increasingly worried about the amount of work they have to do, the stresses that come with it, and the quality of time they spend with their families. Thus, this situation leads to reduced employee morale and work performance. Siswanto [20] demonstrated that the workload is the determinant of employee performance, which could significantly increase employees' performance, or the higher the workload, the higher the output.
The research on the correlation between workload and job performance is contradictory. Several researchers found that workload negatively and insignificantly impacts employee job performance [21,22]. Others asserted that the highest performance occurs when the workload is moderate and that there is a positive correlation between workload and performance [19,20]. A study by [19], for instance, revealed an inverted-U correlation between employee workload and job performance, meaning that output per worker grows as workload increases up to a certain level, beyond which output per employee drops dramatically. The findings from previous studies are contradicting, hence necessitating further study. Thus, we assume that a high workload would impact bank employee job performance. Therefore, we hypothesize that; H 6 Workload significantly impact on Bank Employees' Performance.

Supervisor work-life support, workload, and job performance
Employees who receive high supervisor support will experience low work stress and improved psychological well-being. Hence, more internal resource to deal with increased workload and thus meet the organizational goals of maximizing performance. In other words, employees are driven when they feel supported by their employer and respond by producing high-quality work [67]. An employee's capacity to attain WLB improves when resources such as physical, cognitive, or emotional resources are more than demands. In contrast, this capacity declines when demands exceed the number of resources accessible to the employee [50]. Having a supportive boss may make it easier for workers to rearrange their work to accommodate family obligations, allowing them to have enough resources. Organizational job resources or social resources such as supervisor support, social networking, and psychological resources are essential in increasing workers job satisfaction and performance [27]. Supervisory support is likely to operate as a resource gained at the workplace, enriching the experience of family life and leading to improved job satisfaction and thus employee performance.
Simply put, when workers receive social support from bosses, they can expect a reduction in their burden, whether real or perceived. With the aid of the COR theory, this study proposes that supervisor work-life support stimulates colleague support, which might supply various resources to boost fair workload and, in turn, the high job performance of bank employees. Hence, the workload can mediate one's daily work-to-personal life and family interference between supervisor work-life support and job performance. Because supervisor gives employees more resources to deal with the adverse effects of excessive workloads. Accordingly, we hypothesize that, H 7 Workload mediates the correlation between Supervisor work-life support and job performance.

Employee job performance
From an organizational standpoint, performance is explained as the number of goods and or services produced in a certain period. When treated individually, performance can be defined as effectiveness and efficiency in achieving the aim and the pace of achieving goals [5]. Employee performance is an employee's product, which they produce in exchange for tangible and non-tangible returns [68]. In this case, employee performance is all about employee productivity. The amount of contribution that employee makes to the organization is determined by their performance, which includes the quantity of production, quality of output, participation in work and attendance, and cooperative attitude. Employee performance is a significant aspect of any company's operations. It assists a company in increasing and maximizing its human resource capabilities. As a result, outstanding service delivery and interaction are achieved, touching every part of the business. Thus, whether a manufacturing or service provider organization, performance is critical in determining its success [69]. A bank is a service-oriented business that places a high value on performance to determine success. To succeed, banks need to devise strategies that will promote employee performance. However, improving performance is dependent not just on employees' knowledge, abilities, and efforts but also on organization and human resource practices as well as managers' or supervisors' efforts to create a conducive organizational environment that encourages that effort and success as well as enhance balanced work life. For all these reasons, it is thought that it is vital to investigate the elements that influence employee performance in all companies, particularly those operating in service industries (banks) where labour is heavily utilized.

Methodology
This study examines whether workload and work autonomy as mediators can affect the association between supervisor work-life support and performance. The cross-sectional survey was used to collect the research data of selected commercial banks employees located Central Zone regions of Tanzania. Structured questionnaires were used to gather data for the study from permanent employees in the selected commercial banks. Respondents were kindly invited to participate in this study through email sent to them by their employers. Researchers physically visited timely to distribute questionnaires and request them to respond to questions related to the variable under study. In order to limit the occurrence of response misrepresentation, respondents were informed that their replies would be treated as confidential when responding to the survey. Respondents were asked to complete anonymous, self-administered surveys. Survey questionnaires were distributed to 500 bank employees in these commercial banks. Among the distributed questionnaires, 435 questionnaires, which equals to 87% response rate, were returned. From which 417 questionnaires qualified for analysis after excluding the responses with more than fifteen per cent missing data of survey items related to latent variables of this study. The employed questionnaire survey in this research was adopted from sources and modified by researchers to suit the study context. Twenty-seven items with the Likert scale of five-point starting from 1-'Strongly Disagree to 5-Strongly Agree' were employed to measure constructs under study.

Participant characteristics
Male respondents made up the majority of the employees polled at 53.96% and females at 45.1%. Of which 57.8% of the respondents were between the age of 30 to 40 years, above 40 years were 10%, and 31.9 were under 30. The majority of respondents, 266 (63.79%), had a first degree. Master's degree holders accounted for 50 (11.99%), Advance Diploma holders were 75 (17.98%), diploma holders 18 (4.32%), college certificate 4 (0.96%) and others (secondary certificate) were 4 (0.96%). Regarding work experience, 69.1% of respondents had worked in the banking sector for 1 to 10 years, 22.8% had worked in the banks between 11 to 15 years, and 8.1% had worked for above 15 years. Respondents with such much bank industry knowledge may be able to provide significantly more valuable comments on the survey questions.

Data analysis technique
IBM SPSS version 26.0 and Structural equation modelling were used to analyse research data. IBM SPSS was used to code, enter data and handle descriptive analysis (frequency) of the information gathered from respondents. Following that, SEM was used to analyse the data. PLS-SEM was used to establish the construct's validity and reliability of data through measurement model assessment. Also, by evaluating the structural model, PLS-SEM was used to assess the proposed association between latent variables under study. Because work autonomy, workload, and supervisor support were handled as latent variables, the choice of PLS-SEM was influenced by its aptitude for analysing problems involving latent construct [70].
The researchers tested construct reliability by observing the Cronbach's α, rho-A, and CR (composite reliability) with a minimum value of 0.700 [71]. Similarly, the researchers conducted construct validity to check for AVE as well as discriminant validity by using Fornel Larcker Criterion and HTMT (Heterotrait Monotrait Ratio), and the established criteria were achieved (see Tables 2 and 3). We assessed a Structural model to determine the influence of employees' workload and work autonomy as mediators in the association between supervisor work-life support on job performance among bank employees.

Measurement of latent variables
This study comprises four latent variables. Three of them are exogenous variables, workload (WL), work autonomy (WA), and supervisor work-life support (SWLS), and one endogenous variable is job performance (JP).
The first exogenous variable is Job/work autonomy. The term "autonomy" is the desire to control one's everyday activities. Work autonomy was measured with Six items used to assess job autonomy, adapted from [72]. The sample item for this construct is "I am free to choose the methods to carry out my work." Respondents were asked to respond to the questionnaire's constructs, prepared on a 5-point Likert scale, starting from 1-strongly disagree to 5-strongly agree.
Workload (WL). A job's workload is the amount of work that must be done. Six questions were adopted to measure the workload factor, comparable to those used by [73]. One item for example is "how often does your job require you to work very fast?". In the study, respondents were asked to rate how significant aspects of workload influence their job performance.
Supervisor Support. Five items were used to examine supervisor work-life support (SWLS). The study adapted these items from the work of [74] [75]; one item from this construct is "My supervisor is a good role model for work and nonwork balance. " Employee job performance is an employee's product, which they produce in exchange for tangible and nontangible returns [68]. Employee performance was measured with ten items chosen from the original 14 items [76] used to gauge job performance. An example of one item in this construct is ""I fulfill responsibilities specified in the job description. " The mediating role of work autonomy and workload in the relationship between supervisor work-life support and employee performance (Fig. 1).

Reflective measurement model assessment
The constructs' validity and reliability were assessed using the measurement model (See Table 1). First, most of the model's item loadings of all construct are more than 0.700, which is the minimum allowable value [70,77]. Although a factor loading of > 0.700 is desired [78], researchers in the social science field commonly obtain weaker item loadings (< 0.70). Rather than automatically eliminating indicators, researchers have to evaluate the consequences of removing the item on content, convergent validity, and composite reliability. The outer loadings of items between 0.400 and 0.700 should only be removed if they improve composite reliability or AVE above the suggested value [70,79]. Because the construct values were already over the required level, removing the item WL3 and WA 5, with loading 0.521 & 0.595, respectively, would not have resulted in a significant gain in composite reliability and AVE in the current study. We removed only two items from work autonomy (WA), workload (WL), and job performance (JP) from the analysis to increase the average variance extracted (AVE) (See Fig. 2). Furthermore, an examination of the loadings' confidence intervals revealed that none of the outside loading's values in the items include a zero. As a result, the remaining items in the study were all included for further investigation.(See Table 6 and Fig. 2).
The assessment of reliability was done using CR (composite reliability), rho_A, and Cronbach's alpha. Both statistics were above the recommended value of 0.70 and below 0.950 [70,80]. The study found the rho-A value was "between Cronbach's alpha and composite reliability" [70], and it was also over 0.70, indicating good reliability (See Table 1). Researchers further assess Convergent validity, in which the AVE is a good criterion. The constructs AVE was found to be more than 0.500, which is acceptable convergent validity. When the AVE is 0.5 or more, "it indicates that the latent construct explains at least fifty per cent of the variance in its elements" [81] (See Table 1).

Construct validity (discriminant)
The divergent validity of the latent variables was determined by comparing the associations among them with the square root of each construct AVE [70,82]. The Extracted Average Variance (AVE)' square root, referred to as Fornel-Larcker Criterion was established [83]. Because the values obtained for each latent construct in this research were above the highest   Table 2. HTML of correlations is a recently recommended measure of discriminant validity proposed by [84]. The HTMT correlations are "the mean of all indicators across constructs measuring distinct constructs relative to the mean of the average correlations of indicators measuring the same construct" [70]. HTML of correlations was used to compare the correlations between the latent variables, and values were satisfactory (below the threshold of 0.85) [84].
Therefore, the validity of the study constructs meets the established conditions (See Tables 2 and 3).

Structural model assessment
The structural model mirrors the hypothesized paths in the study's paths. Before assessing the significant path, researchers first examined the multicollinearity of the constructs. Thus, VIF (Variance Inflation Ratio) was used to determine to construct multicollinearity (WL, WA, SWLS, and JP). The recommended VIF values should be below three and not exceed 5 [70,82]. The findings show that the values of the VIF statistics are less than 3, hence no collinearity issue (See Table 4), which satisfies established criteria.
Second, the valuation of the structural model was based on the Q 2 , R 2 , and paths' significance. The model's "predictive power is determined by the strength of each structural path determined by the R 2 value for the endogenous construct" [79]; the value for R 2 is recommended to be equal to or over 0.1 [70]. The R 2 measures "the explanatory power of the because it measures the disparity explained in the endogenous variables" [81]. The study results indicate that all R 2 values are more than 0.1 (See Table 5). Thus, the predictive capability is satisfactory.
Further, Q 2 demonstrates the "predictive relevance of the endogenous constructs" [82]. Q 2 is another way of assessing PLS-SEM predictive model accuracy. A Q 2 greater than '0' indicates that the model has predictive significance [81]. The study results demonstrate that predictive significance is satisfactory since Q 2 is above 0 (see Table 5).
The hypotheses were evaluated to determine the association's relevance among the latent variables. H 1 SWLS influence JP significantly (β = 0.413, t = 9.156, p < 0.05), H 2 investigate whether SWLS has effect on WA. The    findings showed that SWLS positively impacts WA (β = 0.322, t = 6.836, p < 0.05). as a result, H 2 is supported. Again, H 3 work autonomy (WA) indicated a significant effect on JP (β = . 320, t = 2.344, p < 0.050), and thus H 3 was confirmed. H 5 assess the impact of SWLS on employee WL. The results indicate that SWLS has a negative and insignificant influence on WL (β = − 0.045, t = 0.571, p > 0.05). As a result, H 5 is not confirmed, and lastly, H6 results revealed that WL significantly impacts JP ((β = 0.252, t = 4.967, p < 0.050), which means hypothesis H 6 is supported (See Table 5). Table 5 indicates the 95 per cent confidence intervals generated by the 5,000 resamples used in this investigation. A confidence interval that is not zero shows the existence of a tangible link. Moreover, Table 5 summarizes the outcomes of the hypothesis testing of the direct relationship.

Mediation analysis
The mediation assessment was conducted to determine the mediating influence of WA and WL in the association between SWLS and JP. The results in Table 6 demonstrated that the total effect of SWLS on JP is significant (β = 0.437, p < 0.05). With the inclusion of WA and WL as mediating constructs, SWLS's impact on JP remains significant (β = 0.413, p < 0.050). That means bank employees with more job autonomy perceived high support from their supervisors.
The bootstrapping method was used to investigate the relevance of the indirect link between SWLS and job performance through WA and WL. The indirect connection between SWLS and JP through WA was p < 0.05, with a 95% confidence interval of 0.004 to 0.069. At the same time, the mediating role of WL in the correlation between SWLS and JP was p > 0.05 with a confidence interval of − 0.046 to 0.024. As a result, the equations in Table 6 partially met the mediation testing criteria, demonstrating that WA mediated the association between SWLS and job performance, and WL failed to mediate SWLS and JP. The indirect effect of SWLS through WA on JP was substantial (β = 0.036, t = 2.142, p < 0.05). On the other hand, WL fails to mediate the hypothesized association between SWLS and JP; hence it was negative and insignificant (β = − 0.011, t = 0.603, p > 0.05).

Discussion and study implications
This study meant to add to the human resource's body of knowledge by examining the link of supervisor worklife support in the connection between work autonomy and workload on Tanzanian bank employees' performance. The results of the PLS-SEM analysis confirmed that there is a favourable association between work autonomy, workload, and supervisor work-life support on bank employees' job performance. Consistent with the previous research, this study demonstrates that supervisor work-life support was significantly and positively associated with job performance. The result shows that SWLS significantly influences job performance among bank employees. This finding support the earlier studies that show supervisor support and job performance are strongly related [7].
Furthermore, the study found that work autonomy was positively related to employee performance, congruent with [22], which found that work autonomy can help employees improve work performance more efficiently. It means the higher the work autonomy, the high the bank employee's job performance. In contrast, the results of this study, as expected, found that the association between workload and bank employees' performance was significant positively and was in line with [20], who found a positive correlation between workload and employees' job performance. Contrary, other studies [21,22] found a negative association between workload and performance. That means of employee's workload level is crucial in determining organizational productivity.
Further, the result revealed that bank employees' work autonomy significantly mediated the association between supervisor work-life support and employee job performance. It implies that the supervisor role is vital in improving employees' morale and thus increasing organizational output. On the other hand, the linking of employee's workload in the relation between supervisor work-life support and job performance was negative and insignificant. It shows that workload directly affects bank employees' performance. COR theory states that excessive workload consumes an employee's emotional or physical energies or time. It prevents one from acquiring the new resources and hence leaves the employee with insufficient time for skills development and thus may prevent one from cultivating strong interpersonal relationships. In turn, the resources lost due to high workload negatively impact employee well-being and reciprocate with supervisors and coworkers.
In the same line, the study found a positive impact of supervisor work-life support on work autonomy, while the influence of supervisor work-life support on workload is insignificant and negatively related. This insignificant result might be due to a high workload in one role, which takes up a lot of energy and time, making it challenging for employees and leaving them with too little time to study new knowledge or managing a high workload can prevents one from fostering high interpersonal relationships with supervisors and coworkers, negatively impacting job performance.
On top of that, the study has significant implications for managers regarding work design. In particular, the implications for the banking industry. To begin with, granting a high level of autonomy will increase intrinsic motivation, resulting in increased job performance and contentment. Also, this research has demonstrated the importance of supervisor work-life support on bank employees' job performance. As a result, the study suggests that it is vital for businesses and managers to recognize that employees who appreciated by their boss are more likely to perform better at work, engage in activity beyond their job description, and direct their actions to benefit the company. Thus, the manager must discover a means to boost employees' morale to improve organizational performance, such as granting employee work autonomy. Employment happiness can be improved by offering job autonomy and a pleasant, supportive working environment.
Additionally, heavy workloads are not inherent in most occupations [9]. As a result, bank management may ensure that employees are not given excessive workloads. Organizations need to take necessary measures to integrate these findings into their training schedule to overcome this. Organizations should, for example, give workers with sufficient opportunity to obtain control over time available to spend on different job needs in order to reduce workload. Training programs concentrating on time as well as stress management skills may assist employees in setting realistic goals and prioritizing them, allowing them to cope with a heavy workload.
Further, let their leaders/ managers be aware of the importance of employee workload on job performance and the benefits of having good interpersonal relations (being supportive) with workers in the workplace and avoiding exerting control on employees' daily work activities. More importantly, to reduce the disparities between low, normal, and high workloads, these findings must be prioritized to minimize the differences between normal, low, as well as high workloads. They also become essential for management in order to reduce the problems associated with employee workload and employee job performance. For instance, organizations should equip supervisors to recognize the effect of excessive workload, focus their hiring efforts, and promote managers with the knowledge, skills, and capacities to match their positions' mental and physical demands and establish regulations to diminish understaffing. The previous study opined that managers trained on the autonomysupportive factors such as offering reasons for demands, fostering employees' motivating resources, accepting employees' viewpoints, including negative affect expressions, and using non-controlling language exhibited greater autonomy-supportive behaviours with their staff [8].
This shows that companies interested in improving employee attitudes and behaviours towards work and reducing work-life tension should concentrate on Supervisor work-life support. It has been posited that when workers believe their managers are concerned about the demands their families place on them, they may respond by developing more favourable perceptions of the environment in which they perform their jobs. As a result, it may manifest as increased job satisfaction and a greater desire to remain employed by the same company. In turn, this would result in employees experiencing a better life and fewer interference between the realms of work and family. Thus, work-life initiatives, such as those aimed at establishing family-supportive leadership should be promoted by organizations. Thus, granting a high level of autonomy will increase intrinsic motivation, resulting in increased job performance. Because of supportive supervisory behaviours, it may be suitable for organizations to establish methods to increase supervisors' skills in supporting work and life difficulties.

Conclusion and study limitations
The study's assessed the influence of supervisor worklife support in the correlation between workload, work autonomy, and job performance among banking employees in Tanzania's central zone regions. Also, the study evaluated the impact of supervisor work-life support on employee performance. In order to address this main study objective, hypotheses were developed and backed up with theoretical explanations. This study has significant implications for managers when it comes to work design. In particular, it has consequences for the banking industry due to current research findings.
This research adds Human resource (HR) literature and backs up a popular belief based on previous studies. While earlier research has examined a direct link between supervisor support and employee's performance, our study adds to the knowledge by assessing the mediation role of work autonomy and workload on the association between supervisor work-life support and job performance. The result evidenced that the effect of supervisor work-life support on performance is strong and positively mediated by work autonomy. Also, the study showed that supervisor work-life support impacts performance substantially. This finding indicates that a supportive supervisor in work and personal life is a crucial predictor of employee behaviour and attitudes in the workplace. Moreover, workload and work autonomy as mediators significantly influence job performance.
However, contrary to our expectations, workload fails to mediate the association between supervisor worklife support and employee job performance. That means workload does not seem to affect job performance indirectly; instead, it directly affects the endogenous variable.
The study's outcome suggests that workload, work autonomy, and supervisor work-life support are major factors determining bank employees' job performance. Perhaps the most significant contribution of this research is demonstrating that work autonomy is a key mediator in the correlation between supervisor work-life support and bank workers' performance. To our knowledge, this may be the first study to assess on influence of supervisor work-life support on bank employees' workload, work autonomy and performance. Thus, our study shows how the supportive behaviour of supervisors' impacts bank employees' work autonomy, workload and job performance. COR theory asserts that supervisor work-life support acts as a job resource on one's daily work, personal life, and family interference because it gives employees more resources to deal with the adverse impacts of excessive workloads and thus high job performance. Therefore, the study results will help companies interested in improving employee work attitudes and behaviours (e.g. employee job performance) towards work and reducing work-life tension to concentrate on work-family/life supportive supervisor. Mas-machuca [30] asserted that it is simpler for individual worker to perceive a high level of WLB if managers have faith in and support worklife concerns such as providing autonomy in work scheduling and supervisor assistance to employees, as a result, leads to increased employee outcomes (job satisfaction and performance). Also, [34] posit that supervisor fosters value congruence for both employees and supervisors, and it plays a critical role in maximizing employees' organizational outcomes. Given supportive supervisory behaviours is vital resource, it will be suitable for organizations to establish methods to increase supervisors' skills in supporting work and life difficulties.
Finally, the findings of our research should be seen in the context of many limitations or opportunities. First, the findings discussed in this study pertain to a specific sector (banking) in the context of Tanzania's environment, which has distinct culture and her local working environment. This may cause some people to have reservations regarding the question of generalizability. Since culture differs from one nation to another, thus the generalizability of these findings beyond Tanzania should be taken with greater caution. The use of a single industry, on the other hand, appears to eradicate issues that arise as a result of the effects of industry heterogeneity [85] [86]. In the future, cross-national comparative studies can seek more comprehensive knowledge of how the work-life policies investigated in this study of different countries affect bank employees' job performance.
Second, because our study's data were obtained at the same time, it is hard to make causal inferences. As a result, longitudinal investigations are needed to understand further causal inferences on the correlations between latent variables. Moreover, alternative mediators or moderators on the connection between supervisor work-family/life support and employee job performance would be an intriguing area for future research and comparative studies using longitudinal designs. Another disadvantage of this study is that response bias is possible because all of the data was acquired from the same source, which was employees. Specifically, employees' job performance was measured using self-assessment data. As a result, the data may contain self-report bias. The participants in this study may have responded the questions in a way they believed can make them seem to be socially acceptable. It is possible for an employee in the organization to exhibit significant levels of self-presenting while failing to communicate this in an appropriate manner. Future researchers may collect data from a variety of sources, such as immediate employee supervisors, who can provide information about employee performance.