Effects of Napping in Sleep-Restricted Adolescents

NCT ID: NCT02838095

Last Updated: 2016-07-20

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 57 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2015-08-31
• Study Completion Date: 2015-12-31

Brief Summary

To examine the neurobehavioural responses to two successive cycles of sleep restriction and recovery in adolescents, and to determine the benefits of napping on cognitive performance, alertness, and mood. 57 participants, aged 15 to 19 years old, were divided into nap and no-nap groups. Both groups underwent two cycles of sleep restriction and recovery over 15 days. The nap group received an afternoon sleep opportunity lasting 1 hour.

Detailed Description

57 participants (aged 15 to 19 years old) were grouped into nap and no nap groups. Both groups took part in a 15-day protocol that started with 2 9-hour adaptation and baseline nights, followed by two successive cycles of sleep restriction (5-h time-in-bed [TIB]; 01:00-06:00) and recovery (9-h TIB; 23:00-08:00) intended to simulate the weekday sleep loss and weekend attempt to 'catch up' that are familiar to high school students. The nap group received a 1-hour nap opportunity at 14:00 following each sleep-restricted night, while participants in the no nap group watched a documentary. Sleep was monitored with polysomnography on 9 selected nights. Cognitive performance, subjective sleepiness, and mood were assessed 3 times daily (10:00, 15:45, and 20:00).

All participants stayed in air-conditioned, twin-share bedrooms with en-suite bathrooms. Bedroom windows were fitted with blackout panels to ensure participants were not woken up prematurely by sunlight. Earplugs were also provided, and participants were allowed to adjust the temperature of their bedrooms to their personal comfort. 3 main meals were served each day, with snacks being provided for upon request. Caffeinated drinks, unscheduled sleep, and strenuous physical activities were prohibited.

Outside of scheduled sleep, meal, and cognitive testing times, participants spent the majority of their free time in a common room that was illuminated by natural and artificial lighting. They were allowed to read, play non-physically exerting games, watch videos, and interact with research staff and other participants. Participants were under constant supervision by the research staff.

Conditions

Sleep Deprivation; Sleep

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: NONE

Study Groups

No nap

After each night with a 5-hour sleep opportunity, participants did not have a daytime nap opportunity, but instead watched documentaries.

Group Type: NO_INTERVENTION

No interventions assigned to this group

Nap

After each night with a 5-hour sleep opportunity, participants had the chance to take a daytime nap from 14:00 to 15:00.

Group Type: EXPERIMENTAL

Nap

Intervention Type: BEHAVIORAL

A 1-hour daytime nap opportunity

Interventions

Nap

A 1-hour daytime nap opportunity

Intervention Type: BEHAVIORAL

Eligibility Criteria

Inclusion Criteria

• healthy
• no sleep disorder
• body mass index not greater than 30

Exclusion Criteria

• smoker
• habitual short sleeper (time in bed during term time of less than 6 hours and no sign of sleep extension of greater than 1 hour on weekends)
• consumption of more than 5 cups of caffeinated beverages a day
• travelling across more than 2 time zones in the month prior to the study protocol
• diagnosed with any psychiatric conditions

• Minimum Eligible Age: 15 Years
• Maximum Eligible Age: 19 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

National Medical Research Council (NMRC), Singapore

OTHER_GOV

Sponsor Role: collaborator

Duke-NUS Graduate Medical School

OTHER

Sponsor Role: lead

Responsible Party

Michael WL Chee, MBBS

Professor, Neuroscience and Behavioural Disorders Program; Director, Centre for Cognitive Neuroscience

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Michael WL Chee, MBBS

Role: PRINCIPAL_INVESTIGATOR

Duke-NUS Graduate Medical School

Locations

Duke-NUS Medical School

Singapore, Singapore, Singapore

Countries

Singapore

References

Lo JC, Ang JWA, Koa TB, Ong JL, Lim J. Predicting vigilance vulnerability during 1 and 2 weeks of sleep restriction with baseline performance metrics. Sleep Adv. 2022 Oct 25;3(1):zpac040. doi: 10.1093/sleepadvances/zpac040. eCollection 2022.

Reference Type: DERIVED

PMID: 37193393 (View on PubMed)

Lo JC, Koa TB, Ong JL, Gooley JJ, Chee MWL. Staying vigilant during recurrent sleep restriction: dose-response effects of time-in-bed and benefits of daytime napping. Sleep. 2022 Apr 11;45(4):zsac023. doi: 10.1093/sleep/zsac023.

Reference Type: DERIVED

PMID: 35089345 (View on PubMed)

Other Identifiers

NFS2

Identifier Type: -

Identifier Source: org_study_id