{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"institution":[{"name":"medRxiv"}],"indexed":{"date-parts":[[2026,10,24]],"date-time":"2026-10-24T02:18:17Z","timestamp":1792808297396,"version":"4.5.0"},"posted":{"date-parts":[[2026,10,2]]},"group-title":"Neurology","reference-count":24,"publisher":"openRxiv","license":[{"start":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T00:00:00Z","timestamp":1790899200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"name":"National Institute of Neurologic Disease and Stroke","award":["NINDSR01 NS074343"],"award-info":[{"award-number":["NINDSR01 NS074343"]}]},{"name":"University of Pittsburgh Clinical and Translational Science Institute","award":["UL1 TR000005"],"award-info":[{"award-number":["UL1 TR000005"]}]},{"name":"University of Colorado Clinical and Translational Science Award program","award":["UL1 TR001082"],"award-info":[{"award-number":["UL1 TR001082"]}],"id":[{"id":"https:\/\/ror.org\/00jc20583","id-type":"ROR","asserted-by":"crossref"}]},{"name":"Nutrition and Obesity Research Center","award":["P30 DK048520"],"award-info":[{"award-number":["P30 DK048520"]}]},{"name":"National Institutes of Health","award":["K12 HD 055931"],"award-info":[{"award-number":["K12 HD 055931"]}]},{"name":"Parkinson\u2019s Disease Foundation","id":[{"id":"https:\/\/ror.org\/05mx85j86","id-type":"ROR","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"accepted":{"date-parts":[[2026,10,2]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                <jats:sec>\n                  <jats:title>Background<\/jats:title>\n                  <jats:p>Parkinson disease (PD) is associated with increased sedentary time and reduced cardiorespiratory fitness, making exercise an important component of disease management. Although exercise improves cardiorespiratory fitness, individuals with PD vary substantially in their response to exercise. Sedentary time may contribute to this variability, yet whether sedentary time modifies the response to intervention and varying exercise intensities within an intervention is unknown. We examined whether sedentary time interacted with 6 months of moderate-intensity or high- intensity aerobic exercise on maximal oxygen consumption (VO\u2082max) in individuals with PD.<\/jats:p>\n                <\/jats:sec>\n                <jats:sec>\n                  <jats:title>Methods<\/jats:title>\n                  <jats:p>\n                    This secondary analysis used data from the SPARX phase 2 randomized clinical trial including 128 de novo PD patients assigned to high- or moderate-intensity treadmill exercise, or usual care for 6 months. Interactions between randomized group and post-randomization 6-months average sedentary time were assessed for associations with 6-month change in VO\n                    <jats:sub>2<\/jats:sub>\n                    max by using linear regression models corresponding to Analysis of Covariance (ANCOVA) models with interaction.\n                  <\/jats:p>\n                <\/jats:sec>\n                <jats:sec>\n                  <jats:title>Results<\/jats:title>\n                  <jats:p>\n                    The interaction between exercise intensity and sedentary behavior on 6-month change in VO\n                    <jats:sub>2<\/jats:sub>\n                    max in the moderate-intensity group compared with usual care was not significant (\u03b2: -1.78, 95% CI: -3.76 to 0.20, p-value: 0.08), although the sensitivity analysis restricted to complete cases showed a significant interaction where each 10% increase in 6-months average sedentary time was associated with a 2.51 mL\/kg\/min decrease in VO\n                    <jats:sub>2<\/jats:sub>\n                    max change in the moderate-intensity group compared with usual care (\u03b2: -2.51, 95% CI: -4.53 to -0.48, p-value: 0.02). There was no significant interaction between exercise intensity and sedentary behavior on 6-month change in VO\n                    <jats:sub>2<\/jats:sub>\n                    max in the high-intensity group compared with usual care (\u03b2: -1.46, 95% CI: -4.74 to 1.83, p-value: 0.38). The sensitivity analysis showed similar results.\n                  <\/jats:p>\n                <\/jats:sec>\n                <jats:sec>\n                  <jats:title>Conclusions<\/jats:title>\n                  <jats:p>These hypothesis-generating, preliminary findings suggest that sedentary time may modify the response to exercise among individuals participating in moderate-intensity aerobic exercise. Future adequately powered randomized controlled trials are needed to confirm these findings and determine whether sedentary behavior should be considered when prescribing exercise for individuals with PD.<\/jats:p>\n                <\/jats:sec>","DOI":"10.64898\/2026.09.30.26364437","type":"posted-content","created":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T14:50:12Z","timestamp":1790952612000},"source":"Crossref","is-referenced-by-count":0,"title":["Interaction Between Exercise Intensity and Sedentary Behavior on VO\n                  <sub>2<\/sub>\n                  max Change in Patients with De Novo Parkinson Disease: The Study in Parkinson Disease of Exercise (SPARX) Phase 2 Randomized Clinical Trial"],"prefix":"10.64898","author":[{"given":"Byung Joon","family":"Pae","sequence":"first","affiliation":[{"name":"Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tom S.","family":"Novak","sequence":"additional","affiliation":[{"name":"Center for Visual and Neurocognitive Rehabilitation (CVNR), Atlanta VAMC, Decatur, GA, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Garett J.","family":"Griffith","sequence":"additional","affiliation":[{"name":"Department of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Charity G.","family":"Patterson","sequence":"additional","affiliation":[{"name":"Department of Physical Therapy, School of Health and Rehabilitation Sciences, University of Pittsburgh, Pittsburgh, PA, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Madeleine E.","family":"Hackney","sequence":"additional","affiliation":[{"name":"Center for Visual and Neurocognitive Rehabilitation (CVNR), Atlanta VAMC, Decatur, GA, USA"},{"name":"Department of Medicine, School of Medicine, Emory University, Atlanta, GA, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cory L.","family":"Christiansen","sequence":"additional","affiliation":[{"name":"Physical Therapy Program, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel M.","family":"Corcos","sequence":"additional","affiliation":[{"name":"Department of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joe R.","family":"Nocera","sequence":"additional","affiliation":[{"name":"Center for Visual and Neurocognitive Rehabilitation (CVNR), Atlanta VAMC, Decatur, GA, USA"},{"name":"Division of Physical Therapy, School of Medicine, Emory University, Atlanta, GA, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"54368","reference":[{"key":"2026100609501515000_2026.09.30.26364437v1.1","doi-asserted-by":"publisher","DOI":"10.1136\/bmjopen-2024-095610"},{"key":"2026100609501515000_2026.09.30.26364437v1.2","doi-asserted-by":"publisher","DOI":"10.1016\/s0140-6736(14)61393-3"},{"key":"2026100609501515000_2026.09.30.26364437v1.3","doi-asserted-by":"publisher","DOI":"10.1002\/mds.21879"},{"key":"2026100609501515000_2026.09.30.26364437v1.4","doi-asserted-by":"publisher","DOI":"10.1002\/mdc3.14063"},{"key":"2026100609501515000_2026.09.30.26364437v1.5","doi-asserted-by":"publisher","DOI":"10.1038\/s41531-022-00418-4"},{"key":"2026100609501515000_2026.09.30.26364437v1.6","doi-asserted-by":"publisher","DOI":"10.1001\/jamaneurol.2017.3517"},{"key":"2026100609501515000_2026.09.30.26364437v1.7","doi-asserted-by":"publisher","DOI":"10.1212\/WNL.0000000000000644"},{"key":"2026100609501515000_2026.09.30.26364437v1.8","doi-asserted-by":"publisher","DOI":"10.1123\/jpah.2012-0340"},{"key":"2026100609501515000_2026.09.30.26364437v1.9","doi-asserted-by":"publisher","DOI":"10.1139\/apnm-2013-0379"},{"key":"2026100609501515000_2026.09.30.26364437v1.10","doi-asserted-by":"publisher","DOI":"10.1016\/j.cmet.2012.12.012"},{"key":"2026100609501515000_2026.09.30.26364437v1.11","doi-asserted-by":"publisher","DOI":"10.1152\/physrev.00019.2016"},{"key":"2026100609501515000_2026.09.30.26364437v1.12","doi-asserted-by":"publisher","DOI":"10.1097\/npt.0000000000000169"},{"key":"2026100609501515000_2026.09.30.26364437v1.13","doi-asserted-by":"publisher","DOI":"10.1007\/s00415-025-13085-1"},{"key":"2026100609501515000_2026.09.30.26364437v1.14","first-page":"404","article-title":"3rd, Naughton, J. 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