Effects of high-intensity interval training and moderate-intensity continuous training on non-motor symptoms in patients with Parkinson's disease: a randomised pilot trial

Objective To explore whether high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) have different effects on non-motor symptoms in patients with Parkinson’s disease (PD). Methods In this 24-week, randomized, controlled, investigator–blinded pilot trial, 33 participants with PD (Hoehn and Yahr stages 1–2; aged 50–80 years) were allocated to HIIT (3 days/week, 60% maximum aerobic power for 30–50 seconds with 1 minute rest intervals), MICT (3 days/week, 50% peak oxygen consumption), or control (usual care) groups. The primary clinical outcome was a 24-week change in the Non-Motor Symptoms Scale (NMSS) score. The secondary clinical outcomes were 24-week changes in the scores of specific non-motor questionnaires covering neuropsychiatric, sleep-related, autonomic, and sensory symptoms. Results NMSS score changes did not differ significantly among the three groups (Bonferroni-adjusted p >0.6 in all). In the secondary clinical outcome analyses, the MICT group showed a greater improvement in Beck Depression Inventory scores (median difference, 3.5 points; 95% confidence interval [CI], 1.4 to 6.0; Bonferroni-adjusted p =0.016) and, to a lesser extent, Beck Anxiety Inventory scores (median difference, 2.0 points; 95% CI, 0.0 to 10.8; Bonferroni-adjusted p =0.054) compared with those of the control group. However, these trends were not observed in the HIIT group when compared with the control group (Bonferroni-adjusted p >0.9 in all). There were no significant differences in the other secondary outcomes between the groups. Conclusion This trial did not show the potential benefits of HIIT or MICT on overall non-motor symptoms in patients with PD. However, MICT may be more effective than HIIT in alleviating mood symptoms, which requires further large-scale investigation. Trial registration CRIS (cris.nih.go.kr) identifier: KCT0007130 ### Competing Interest Statement The authors have declared no competing interest. ### Clinical Trial cris.nih.go.kr (KCT0007130) ### Funding Statement This work was supported by the National Research Foundation (NRF) grant funded by the Korea government (MSIT) (No. 2021R1C1C1011822). ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The study design was approved by the Institutional Review Board of the Inha University Hospital (2022-01-030). I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes The full dataset will be available on reasonable request from any qualified investigator.