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Jennifer A. Schrack, PhD

  • Assistant Professor

Departmental Affiliations

  • Epidemiology (Primary)
    • Division: Epidemiology of Aging
  • Krieger School of Arts and Sciences (Joint)

Center & Institute Affiliations

Contact Information

615 N. Wolfe Street
Room E7144
Baltimore, Maryland 21205

410-502-9328

View Current Courses

Education

PhD, BSPH, 2011
MS, University of Michigan, 2002

Overview

Dr. Schrack's primary area of research is the epidemiological assessment of physical activity and fatigability, and their corresponding associations with health and longevity in older populations.

Physical activity and fatigability are modifiable risk factors for functional decline, disease development, and disability in older populations. These risk factors are intrinsically linked to physiologic regulation of energy expenditure at rest and during movement. Until recently, measures of human performance were limited to laboratory settings. However, the advent of wearable technology presents an unprecedented opportunity to better understand how quantities, patterns, and trends of daily activity predict physical and cognitive outcomes with aging. These technologically advanced monitors have the potential to ultimately transform clinical research and be widely used as preventative therapy tools. 

Using advanced data collection and analytical methodology, Dr. Schrack is working to elucidate mechanisms of physical and cognitive decline by developing and validating new metrics of physical activity and fatigability for older populations.  This work is crucial to understanding changes in physical and cognitive functioning with age that will inform future interventions aimed at curbing threats to healthy longevity including high fatigability, physical disability, and dementia.

Honors and Awards

2018 Golden Apple Award for Excellence in Teaching: Honors in Public Health

2017 Johns Hopkins University Catalyst Award

2014 - 2017 K01 Career Development Award, National Institute on Aging

2014 - 2015 Johns Hopkins Roybal Center Faculty Pilot Award

2013 - 2015 Johns Hopkins Center for AIDS Research Faculty Development Award

Selected publications

  • Schrack JA, Leroux A, Fleg J, Zipunnikov V, Simonsick EM, Studenski S, Crainiceanu C, Ferrucci L. Using heart rate and accelerometry to define quantity and intensity of daily physical activity in older adults. J Gerontol A Biol Med Sci. 2018 Apr 17;73(5):668-675. doi: 10.1093/Gerona/gly029. PMID: 29509832
  • Schrack JA, Zipunnikov V, Goldsmith AJ, Crainiceanu CM, Simonsick EM, Ferrucci L.  Assessing the “Physical Cliff”: Detailed Quantification of Physical Activity and Aging. J Gerontol A Biol Sci Med Sci. 2014 Aug;69(8):973-9. PMID: 24336819.
  • Schrack JA, Cooper R, Koster A, Shiroma EJ, Murabito JM, Rejeski WJ, Ferrucci L, Harris TB. Assessing Daily Physical Activity in Older Adults: Unraveling the Complexity of Monitors, Measures, and Methods. J Gerontol A Biol Sci Med Sci. 2016 Aug;71(8): 1039-48. PMID: 26967472
  • Gresham G, Dy S, Zipunnikov V, Studenski SA, Simonsick EM, Ferrucci L, Schrack JA. Fatigability and Endurance Performance in Adults with a History of Cancer: Analyses from the Baltimore Longitudinal Study of Aging. Cancer. 2018 Mar 15;124(6):1279-1287. Doi: 10.1002/cncr.31238. PMID: 29419879
  • Wanigatunga AA, Varadhan R, Simonsick EM, Studenski S, Ferrucci L, Schrack JA. Longitudinal relationship between interlukin-6 and perceived fatigability among well-functioning adults in mid-to-late life. J Gerontol A Biol Med Sci. 2018 May 26. doi: 10.1093/gerona/gly120. [Epub ahead of print] PMID: 29846512
  • Baltimore Longitudinal Study of Aging
  • MACS Energy Expenditure Study