INTRODUCTION/AIMS Metabolic syndrome (MetS) has been postulated to play a role in the progression of Parkinson’s disease (PD). Several lines of evidence also suggest that forced-rate exercise (FRE) is a potent therapy to alleviate motor and non-motor symptoms of PD, and perhaps MetS severity (MSS). However, long-term exercise adherence in people with PD (PWP) is poor. Alternative/adjunct therapies are therefore warranted. Photobiomodulation (PBM) is an emerging non-pharmaceutical/non-exercise therapy that may improve PD symptoms. Thus, this study aimed to determine the impact of FRE and/or PBM relative to usual care on MSS in PWP. METHODS Twenty participants diagnosed with PD (aged 40-80yrs) were randomised into one of four groups assigned to a different sequence of the study interventions or SHAM treatment across four 8-week study periods, each separated by a 4-week wash-out period: (1) Group A-B-C-D (n=5); (2) Group B-D- A-C (n=5); (3) Group C-A-B-D (n=5); (4) Group D-C-B-A (n=5). A-B-C-D represents PBM, FRE, FRE+PBM, and SHAM, respectively. Z-scores were derived from levels of MetS risk factors to determine the MSS (MetS z-score). Responders to a clinically significant change in MetS z-score was classified as those demonstrating a reduction of at least 0.48. RESULTS Our preliminary analysis included 17 participants with 30 complete pre- and post-MetS z-score data sets (FRE, n=5; FRE+PBM, n=7; PBM, n=9; SHAM, n=9). There was no statistically significant difference between groups in MSS change from pre-to-post intervention (p=0.82). However, the FRE group showed the greatest proportion of MSS responders: 60% (3/5) compared to FRE+PBM (43%, 3/7), PBM (44%, 4/9), and SHAM (33%, 3/9). CONCLUSION FRE may be the most efficacious method of clinically improving MSS. However, our study also suggests that a combined FRE+PBM or PBM alone could be used as an initial or supplementary treatment in ameliorating MSS and thus potentially PD progression.