Type of supervision does not affect attendance or physical fitness in an 8-week workplace exercise intervention

Abstract

Introduction: Low cardiorespiratory fitness (CRF) and muscular strength are significant metabolic, cardiovascular andmortality risk factors. The workplace has become a key setting for physical activity promotion; however attrition rates up to 75% in workplace exercise interventions have been reported. Therefore, this study investigated the effect of providing different types of supervision in a university workplace exercise intervention on attendance and fitness levels. Methods: This pilot randomised controlled trial allocated 46 university staff (mean± SD; 37 female; aged 42.5±11 yrs; BMI 25.7±4.0 kgm−2;waist circumference84.7±12.7 cm) toeither1:1 supervised (SUP;N=22) or indirectly supervised (IND;N=24) exercise groups. The 1:1 SUP group received individual supervision each exercise session, while the IND group received supervision for safety only, with assistance provided if requested or required. Each participant completed an 8-week individually tailored moderateto-high intensity aerobic and resistance exercise program at an onsite gymnasium, based on American College of Sports Medicine guidelines. Participants were required to attend at least once a week but had the opportunity to complete up to five training sessions perweek. Total attendance (total number of exercise sessions performed), total aerobic training volume (METmin), and total resistance training load (sets× reps×weight) were calculated. Cardiorespiratory fitness was predicted using a progressive submaximal cycle test (Monark 828E, Sweden), while maximal knee flexion and extension strength were measured at 60degrees s−1 with a Biodex (Biodex Medical Systems, USA) before and after the intervention. Results: Independent sample t-tests found no significant differences between groups for age, BMI, waist circumference, CRF or muscle strength prior to the intervention (p>0.05); nor any significant differences between groups for total attendance (p=0.94), total aerobic volume (METmin) completed (p=0.73) or total resistance load completed (p=0.88) over the 8-week intervention. One-way repeatedmeasures ANOVA revealed significant improvements in CRF (p<0.001), absolute and relative kneeflexion strength (p<0.05) as well as absolute and relative knee extension strength (p<0.01). No between-group differences were found for any variable. Discussion: This study found that CRF and lower body strength improved with a short workplace exercise intervention, irrespective of the type of supervision. The supervision type did not affect exercise session attendance, or exercise dose completed. Therefore, providing 1:1 exercise supervision was not more advantageous than indirect supervision for CRF or muscular strength in a university workplace exercise intervention.