# A Personalized Behavioral Intervention to Improve Physical Activity, Sleep and Cognition in Sedentary Older Adults

> **NIH NIH R00** · JOHNS HOPKINS UNIVERSITY · 2020 · $249,000

## Abstract

PROJECT SUMMARY/ABSTRACT
The proposed project aims to identify the optimal features of daytime napping and physical activity for cognition
in older adults (K99) and examine the effects of an innovative, personalized behavioral intervention on
promoting physical activity, healthy napping, sleep and cognitive function in sedentary older adults (R00). In
the K99 phase, to ensure the successful completion of the R00 project and facilitate the achievement of my
career development goals, I will follow an intensive training plan that incorporates courses, laboratory training,
mentoring, and structured activities. In addition, a retrospective study will be conducted using two large
longitudinal cohorts of older adults in the United States to examine the associations of daytime physical activity
and nocturnal sleep with cognitive decline over 4-6 years. The K99 study will examine: 1) baseline associations
of napping characteristics, physical activity and nocturnal sleep duration with cognition; 2) whether baseline
napping, physical activity and nocturnal sleep duration predict cognitive decline at the 4-6 year follow-up; and 3)
relationships between changes in physical activity and nocturnal sleep duration and changes in cognitive
function at follow-up. Building off the K99, in the R00 phase, a randomized controlled trial will be conducted in
older adults (without dementia) with both sedentary lifestyle and nocturnal sleep complaints to examine the
effectiveness of a 24-week personalized behavioral intervention implemented with smartwatch technology on
promoting physical activity, nocturnal sleep, and cognition compared against a control group; we have
successfully tested this in a pilot study. Serum inflammatory biomarkers will be assessed to explore
hypothesized mechanisms for associations among the study outcomes. In order to optimize outcomes at the
subject level, a personalized physical activity plan will be calculated based on the individual’s characteristics,
personal circadian rhythm at baseline, and the optimal characteristics of napping and physical activity that
were identified in the K99 phase. The R00 study will examine: 1) whether the intervention increases
participants’ non-nap period physical activity, optimizes napping duration, and enhances nocturnal sleep; 2)
whether the intervention improves participants’ overall cognitive performance; 3) whether the relationship
between the study intervention and cognitive performance is mediated by changes in physical activity, healthy
nap duration, and nocturnal sleep duration; and 4) (exploratory aim) if the proposed intervention changes
serum inflammatory biomarkers, including cytokines (IL-6, IL-1ß, TNF-α) and C-reactive protein, and whether
these biomarkers relate to changes in physical activity, sleep, and cognitive function. Upon completion, this
proposal will provide important insights on the optimal features of physical activity and napping for cognitive
function. The proposed intervention m...

## Key facts

- **NIH application ID:** 9973230
- **Project number:** 5R00NR016484-04
- **Recipient organization:** JOHNS HOPKINS UNIVERSITY
- **Principal Investigator:** Junxin Li
- **Activity code:** R00 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $249,000
- **Award type:** 5
- **Project period:** 2019-06-01 → 2022-05-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9973230

## Citation

> US National Institutes of Health, RePORTER application 9973230, A Personalized Behavioral Intervention to Improve Physical Activity, Sleep and Cognition in Sedentary Older Adults (5R00NR016484-04). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/9973230. Licensed CC0.

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