Poster Presentation Australian and New Zealand Obesity Society Annual Scientific Conference 2026

Physical activity, mental health, and quality of life in class 3 obesity: a 12-month multidisciplinary weight management cohort  (#127)

Mohammad Riashad Monjur 1 , Kate McGrath 2 , Mohammed Mohsin 3 , Alan Huang 1 , Kathy Grudzinskas 1 , Nic Kormas 1 , Janet Conti 2 , Phillipa Hay 1 2 , Milan Piya 1 2
  1. South Western Sydney Metabolic Rehabilitation and Bariatric Program, Sydney
  2. Western Sydney University, Sydney
  3. Mental Health Research and Teaching Unit, South Western Sydney Local Health District, Sydney

Background

Class 3 obesity is associated with elevated psychological distress and reduced health-related quality of life (HRQoL). Physical activity is a less explored component of multidisciplinary weight management programs (WMPs), and its independent contribution to psychological outcomes remains poorly characterised in this population. This study aimed to examine the impact of physical activity and capacity on HRQoL and psychological outcomes following participation in a multidisciplinary WMP.

Methods

This 12-month retrospective cohort study included 137 adults with Class 3 obesity in a multidisciplinary WMP between May 2018 and May 2025. Participants completed the K-10 (psychological distress), SF-12 (HRQoL), and IPAQ-SF (physical activity) questionnaires. A subset of participants also completed the 6-Minute Walk Test (6MWT) and 1-Minute Sit-to-Stand Test (1MSTST). Paired t-tests were used to examine changes within individuals. Multiple linear regression evaluated the association of physical activity (IPAQ-SF) and physical capacity (6MWT, 1MSTST) on psychological outcomes, adjusting for age, sex, and weight loss.

Results

The 137 participants had a mean age of 49.2±13.2 years, BMI 52.6±8.8 kg/m², weight 148.0±31.9 Kg, 72% were female and 35.3% had type 2 diabetes. At 12 months, there was significant weight loss (−7.3±9.4kg, p<0.001), and significant improvement in all parameters: psychological distress (K-10 score: 25.0 to 20.8, p<0.001), Physical and Mental HRQoL (32.0 to 35.2, p<0.001; 38.7 to 43.6; p<0.001, respectively), as well as physical activity (IPAQ-SF) (p<0.005), and physical capacity (6MWT and 1MSTST, p<0.001). In adjusted regression, greater physical activity (IPAQ-SF:β=0.19, p<0.05) and higher walking capacity (6MWT:β=0.40, p<0.05) independently predicted improvements in Mental HRQoL. Physical activity and capacity did not independently predict K-10, or physical HRQoL after adjusting for weight loss.

Conclusions

In Class 3 obesity, enhancements in physical activity and physical capacity predicted improvements in Mental HRQoL independent of weight loss. This finding supports the importance of incorporating targeted exercise interventions within multidisciplinary WMPs.