biostudies-literatureHoltman SNICHD NIH HHSNCATS NIH HHSNational Institute for HealthNIDDK NIH HHSzsae273https://www.ebi.ac.uk/biostudies/studies/S-EPMC12477115biostudies-literatureUnknown48(2)<h4>Study objectives</h4>Evaluate objectively measured circadian rhythms following 1-week of at-home sleep extension in habitually short-sleeping adolescents.<h4>Methods</h4>Twenty-six participants (16.1 ± 1.2 years, 69% female, and 65% White non-Hispanic) with insufficient sleep (≤7 h on school nights) were randomized to 1 week of typical sleep (TS; usual school schedule) and sleep extension (EXT; ≥1-h additional time in bed) in counterbalanced order with a 1-month washout between conditions. Home monitoring of actigraphy-estimated sleep and light exposure was assessed during both weeks. Hourly in-laboratory evening/morning dim-light salivary melatonin samples were obtained and onset (DLMOn) and offset (DLMOff) were calculated following each condition.<h4>Results</h4>Sleep duration increaSleepChanges in circadian timing following a 1-week in-home sleep extension manipulation in habitually short-sleeping adolescents.PMC12477115NIH NCATS Colorado CTSA UL1 TR002535K23 DK117021NIDDK K23DK117021NIH BIRCWH K12HD057022R03 DK131225UL1 TR002535K12 HD057022Bowen AENadeau KJWright KPCooper EHoltman SHawkins SCree MGSimon SLBrinton JTfalseChanges in circadian timing following a 1-week in-home sleep extension manipulation in habitually short-sleeping adolescents.<h4>Study objectives</h4>Evaluate objectively measured circadian rhythms following 1-week of at-home sleep extension in habitually short-sleeping adolescents.<h4>Methods</h4>Twenty-six participants (16.1 ± 1.2 years, 69% female, and 65% White non-Hispanic) with insufficient sleep (≤7 h on school nights) were randomized to 1 week of typical sleep (TS; usual school schedule) and sleep extension (EXT; ≥1-h additional time in bed) in counterbalanced order with a 1-month washout between conditions. Home monitoring of actigraphy-estimated sleep and light exposure was assessed during both weeks. Hourly in-laboratory evening/morning dim-light salivary melatonin samples were obtained and onset (DLMOn) and offset (DLMOff) were calculated following each condition.<h4>Results</h4>Sleep duration increa2025-01-01T00:00:00Z2025 Feb2026-06-04T00:12:14.035Z2026-05-03T03:11:56.224ZS-EPMC124771153958218210.1093/sleep/zsae273