The Effect of a Structured Workplace Exercise Program on 360-Degree Performance Evaluation, Job Motivation, Productivity, and Quality of Work Life (PADRA-EXER)

This study employs a quasi-experimental, single-group pre-test/post-test design with a mixed-methods (quantitative-qualitative) approach. The study is conducted at a medical protective apparel and healthcare sanitary wear manufacturing plant in Sanandaj, Kurdistan Province, Iran. Workers primarily perform sedentary-to-light manual tasks including fabric cutting, sewing, quality inspection, and packaging under a two-shift rotation system. The study period runs from April to July 2025 (1 Ordibehesht to 24 Tir 1404, Iranian calendar). Baseline (T1) assessments are completed one week before session 1; post-intervention (T2) assessments are completed within one week of session 24. The study protocol was approved by the Research Ethics Committee of Islamic Azad University, Sanandaj Branch (Ethics Code: IR.IAU.SANANDAJ.REC.1405.152). Written informed consent is obtained from all participants before enrolment.

Participants: All 150 employees of the facility are invited for eligibility screening. A licensed occupational medicine physician conducts clinical examinations supplemented by the Physical Activity Readiness Questionnaire (PAR-Q). Employees with uncontrolled cardiovascular disease, severe respiratory disorders, musculoskeletal conditions incompatible with moderate-intensity exercise, pregnancy, or other physician-identified contraindications are excluded. Eligible employees who provide written informed consent are enrolled. Sample size adequacy is confirmed using Cochran's formula for finite populations (N = 150; 95% CI; margin of error = 0.05; p = q = 0.50), and statistical power is verified using G*Power 3.1.

Intervention Protocol: The 12-week structured exercise program comprises 24 sessions (2 × 60 min/week), delivered by a fitness instructor holding a Grade-2 certification from the Physical Fitness Federation of the Islamic Republic of Iran. Sessions are consistently held at 10:00 AM before shift handovers. The facility's dedicated sports hall provides a climate-controlled environment (25-26°C; 60% relative humidity) consistent with ACSM guidelines for moderate-intensity aerobic exercise. Each session includes a 10-minute warm-up with joint mobility and dynamic stretching, a 40-minute main phase combining intermittent aerobic exercise (60-75% of heart rate reserve) with functional core exercises, calisthenics, and cooperative small-sided games, and a 10-minute cool-down with static stretching, spinal elongation, and guided diaphragmatic breathing. Aerobic intensity is targeted at 60-75% of heart rate reserve using the Karvonen formula, monitored via the Borg Rating of Perceived Exertion (RPE; 6-20 scale; target 12-14). All phases are instructor-led; no self-directed activities are included.

Outcome Measures: Four validated instruments are administered at baseline (T1) and post-intervention (T2). (1) The 40-item Herzberg Dual-Factor Motivation Questionnaire (Darchini, 2015) assesses two independent subscales: Intrinsic/Motivator factors (20 items) and Extrinsic/Hygiene factors (20 items), using a 5-point Likert scale. (2) The 26-item AGIO Human Resource Productivity Scale (Hersey and Blanchard, 1980; validated by Mehri, 2013) assesses seven subscales: Ability, Role Clarity, Organizational Support, Motivation, Feedback, Credibility, and Environmental Fit, using a 5-point Likert scale. (3) A 360-degree performance evaluation questionnaire (Poursoltani et al., 2010) collects ratings from four sources: supervisor, peer, subordinate, and self. (4) The Walton Quality of Work Life Questionnaire (Walton, 1973; Iranian validation by Rahimi, 2005) assesses eight dimensions including fair compensation, safe working conditions, and growth opportunities.

Statistical Analysis Plan: All analyses will use IBM SPSS Statistics v26.0. Composite scale scores (≥ 10 items) will be treated as continuous interval-level data for parametric analyses. Shapiro-Wilk tests will verify univariate normality. For the primary pre-post comparisons, paired-samples t-tests will be used with a Bonferroni-adjusted significance threshold. For the cross-sectional association between post-intervention motivation, 360-degree appraisal, and productivity, an enter-method multiple linear regression will be used. A supplementary regression will include T1 motivation as a covariate. Model assumptions will be verified (VIF < 2.0 for multicollinearity; Durbin-Watson for autocorrelation). One-way ANOVA with partial eta-squared will examine whether demographic characteristics moderate post-intervention outcomes. Qualitative interview data from 10 semi-structured interviews will undergo thematic content analysis (open, axial, and selective coding) as a planned exploratory component of the study.