{"doi":"10.1161/circoutcomes.123.010731","title":"Text Messages to Promote Physical Activity in Patients With Cardiovascular Disease: A Micro-Randomized Trial of a Just-In-Time Adaptive Intervention","abstract":"<jats:sec>\n            <jats:title>BACKGROUND:</jats:title>\n            <jats:p>Text messages may enhance physical activity levels in patients with cardiovascular disease, including those enrolled in cardiac rehabilitation. However, the independent and long-term effects of text messages remain uncertain.</jats:p>\n          </jats:sec>\n          <jats:sec>\n            <jats:title>METHODS:</jats:title>\n            <jats:p>The VALENTINE study (Virtual Application-supported Environment to Increase Exercise) was a micro-randomized trial that delivered text messages through a smartwatch (Apple Watch or Fitbit Versa) to participants initiating cardiac rehabilitation. Participants were randomized 4× per day over 6-months to receive no text message or a message encouraging low-level physical activity. Text messages were tailored on contextual factors (eg, weather). Our primary outcome was step count 60 minutes following a text message, and we used a centered and weighted least squares mean method to estimate causal effects. Given potential measurement differences between devices determined a priori, data were assessed separately for Apple Watch and Fitbit Versa users over 3 time periods corresponding to the initiation (0–30 days), maintenance (31–120 days), and completion (121–182 days) of cardiac rehabilitation.</jats:p>\n          </jats:sec>\n          <jats:sec>\n            <jats:title>RESULTS:</jats:title>\n            <jats:p>One hundred eight participants were included with 70 552 randomizations over 6 months; mean age was 59.5 (SD, 10.7) years with 36 (32.4%) female and 68 (63.0%) Apple Watch participants. For Apple Watch participants, text messages led to a trend in increased step count by 10% in the 60-minutes following a message during days 1 to 30 (95% CI, −1% to +20%), with no effect from days 31 to 120 (+1% [95% CI, −4% to +5%]), and a significant 6% increase during days 121 to 182 (95% CI, +0% to +11%). For Fitbit users, text messages significantly increased step count by 17% (95% CI, +7% to +28%) in the 60-minutes following a message in the first 30 days of the study with no effect subsequently.</jats:p>\n          </jats:sec>\n          <jats:sec>\n            <jats:title>CONCLUSIONS:</jats:title>\n            <jats:p>In patients undergoing cardiac rehabilitation, contextually tailored text messages may increase physical activity, but this effect varies over time and by device.</jats:p>\n          </jats:sec>\n          <jats:sec>\n            <jats:title>REGISTRATION:</jats:title>\n            <jats:p>\n              URL:\n              <jats:ext-link xmlns:xlink=\"http://www.w3.org/1999/xlink\" ext-link-type=\"uri\" xlink:href=\"https://www.clinicaltrials.gov\">https://www.clinicaltrials.gov</jats:ext-link>\n              ; Unique identifier: NCT04587882.\n            </jats:p>\n          </jats:sec>","journal":"Circulation: Cardiovascular Quality and Outcomes","year":2024,"id":625236,"datarank":0.42498200160843247,"base_score":2.833213344056216,"endowment":2.833213344056216,"self_citation_contribution":0.42498200160843247,"citation_network_contribution":0.0,"self_endowment_contribution":0.42498200160843247,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":16,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":null,"is_data_producer":false,"deposit_databanks":null,"is_oa":false,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":null,"fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1179310,"name":"Jieru Shi","orcid":"0000-0002-3149-0466","position":1,"is_corresponding":false},{"id":717841,"name":"Kashvi Gupta","orcid":"0000-0002-3083-1804","position":2,"is_corresponding":false},{"id":1616688,"name":"Rachel Stevens","orcid":null,"position":3,"is_corresponding":false},{"id":1616689,"name":"V.Swetha E. Jeganathan","orcid":null,"position":4,"is_corresponding":false},{"id":1616690,"name":"Evan Luff","orcid":null,"position":5,"is_corresponding":false},{"id":1616691,"name":"Thomas Boyden","orcid":null,"position":6,"is_corresponding":false},{"id":240115,"name":"Bhramar Mukherjee","orcid":"0000-0003-0118-4561","position":7,"is_corresponding":false},{"id":1616692,"name":"Sarah Kohnstamm","orcid":null,"position":8,"is_corresponding":false},{"id":1616693,"name":"Vlad Taralunga","orcid":"0009-0004-0555-8967","position":9,"is_corresponding":false},{"id":227521,"name":"Vik Kheterpal","orcid":"0000-0002-4752-4229","position":10,"is_corresponding":false},{"id":240114,"name":"Sachin Kheterpal","orcid":"0000-0002-6546-0273","position":11,"is_corresponding":false},{"id":418166,"name":"Ken Resnicow","orcid":"0000-0003-1416-9627","position":12,"is_corresponding":false},{"id":74886,"name":"Susan A. Murphy","orcid":"0000-0002-2032-4286","position":13,"is_corresponding":false},{"id":716816,"name":"Walter Dempsey","orcid":"0000-0002-6510-4121","position":14,"is_corresponding":false},{"id":232381,"name":"Predrag Klasnja","orcid":"0000-0002-4570-703X","position":15,"is_corresponding":false},{"id":240113,"name":"Brahmajee K. Nallamothu","orcid":"0000-0003-4331-6649","position":16,"is_corresponding":false},{"id":436553,"name":"Jessica R. Golbus","orcid":"0000-0002-9538-3926","position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"resolved":true,"title":"Text Messages to Promote Physical Activity in Patients With Cardiovascular Disease: A Micro-Randomized Trial of a Just-In-Time Adaptive Intervention","abstract":"<jats:sec>\n            <jats:title>BACKGROUND:</jats:title>\n            <jats:p>Text messages may enhance physical activity levels in patients with cardiovascular disease, including those enrolled in cardiac rehabilitation. However, the independent and long-term effects of text messages remain uncertain.</jats:p>\n          </jats:sec>\n          <jats:sec>\n            <jats:title>METHODS:</jats:title>\n            <jats:p>The VALENTINE study (Virtual Application-supported Environment to Increase Exercise) was a micro-randomized trial that delivered text messages through a smartwatch (Apple Watch or Fitbit Versa) to participants initiating cardiac rehabilitation. Participants were randomized 4× per day over 6-months to receive no text message or a message encouraging low-level physical activity. Text messages were tailored on contextual factors (eg, weather). Our primary outcome was step count 60 minutes following a text message, and we used a centered and weighted least squares mean method to estimate causal effects. Given potential measurement differences between devices determined a priori, data were assessed separately for Apple Watch and Fitbit Versa users over 3 time periods corresponding to the initiation (0–30 days), maintenance (31–120 days), and completion (121–182 days) of cardiac rehabilitation.</jats:p>\n          </jats:sec>\n          <jats:sec>\n            <jats:title>RESULTS:</jats:title>\n            <jats:p>One hundred eight participants were included with 70 552 randomizations over 6 months; mean age was 59.5 (SD, 10.7) years with 36 (32.4%) female and 68 (63.0%) Apple Watch participants. For Apple Watch participants, text messages led to a trend in increased step count by 10% in the 60-minutes following a message during days 1 to 30 (95% CI, −1% to +20%), with no effect from days 31 to 120 (+1% [95% CI, −4% to +5%]), and a significant 6% increase during days 121 to 182 (95% CI, +0% to +11%). For Fitbit users, text messages significantly increased step count by 17% (95% CI, +7% to +28%) in the 60-minutes following a message in the first 30 days of the study with no effect subsequently.</jats:p>\n          </jats:sec>\n          <jats:sec>\n            <jats:title>CONCLUSIONS:</jats:title>\n            <jats:p>In patients undergoing cardiac rehabilitation, contextually tailored text messages may increase physical activity, but this effect varies over time and by device.</jats:p>\n          </jats:sec>\n          <jats:sec>\n            <jats:title>REGISTRATION:</jats:title>\n            <jats:p>\n              URL:\n              <jats:ext-link xmlns:xlink=\"http://www.w3.org/1999/xlink\" ext-link-type=\"uri\" xlink:href=\"https://www.clinicaltrials.gov\">https://www.clinicaltrials.gov</jats:ext-link>\n              ; Unique identifier: NCT04587882.\n            </jats:p>\n          </jats:sec>","is_dataset_classified":null,"base_score":0.0,"endowment":0.0,"datacite_reuse_total":0,"file_count":0,"downloads":0,"views":0,"has_version_chain":false,"is_dataset":false,"is_oa":false,"pmid":null,"pmcid":null,"openalex_id":null,"authors":[],"funders":[],"total_grants":0,"fwci":null,"citation_percentile":null,"influential_citations":0,"citation_trend":[],"oa_status":"green","license":null,"oa_locations":[{"url":"https://pmc.ncbi.nlm.nih.gov/articles/PMC11251861/pdf/nihms-1996824.pdf","host_type":"repository"},{"url":"https://www.ahajournals.org/doi/full/10.1161/CIRCOUTCOMES.123.010731","host_type":"publisher"}],"fields_of_study":[],"mesh_terms":[],"keywords":[],"sdg_mappings":[],"linked_datasets":[],"clinical_trials":[],"software_tools":[],"database_accessions":[],"source":"live","citation_network_status":"fetched"},"created_at":"2026-08-04T06:12:15.217694Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}