Kathleen Janz

Professor Emeritus


  • Physical activity
  • Health outcomes

Courses taught

  • Contemporary Issues in Health Promotion
  • Epidemiology of Physical Activity
  • Exercise Testing and Prescription
  • Health Promotion Research and Program Models
  • Health Promotion Theory and Practice
  • Methods: Health Education for Elementary Teachers
  • Physical Activity through the Lifespan
  • Women's Health Symposium

Research interests

  • Physical activity and physical fitness as determinants of health outcomes
  • Electronic monitoring of physical activity
  • Longitudinal tracking of physical activity

Recent awards, honors, prestigious appointments

Appointed, FitnessGram Scientific Advisory Board, The Cooper Institute. Guidance on structure and direction of the U.S. national youth assessment program (Presidential Youth Fitness Program).  Provide technical content expertise in muscle- and bone-strengthening physical activity and physical fitness. 2017-present.

Distinguished Lecturer, Physical Activity Across the Lifespan for Bone Health, Beijing Sports Institute, Beijing, China, January 14-17, 2019.

Appointed, Evidence-based Consensus Recommendations on Youth Collision and Contact Sport Writing Committee. Four Corners Consortium and American College of Sports Medicine, 2018-2019.

Invited Featured Speaker, Physical Activity Pattern Development from Infancy Through Adolescence. Modeling the Activity of Children and Youth Meeting. National Cancer Institute, NIH, Aug 30-31, 2018.

Appointed, 2018 Physical Activity Guidelines Advisory Committee. One of 17 nationally recognized experts in physical activity and health. U.S. Department of Health and Human Services, 2016-2018. 

Appointed, Presidents’ Commission American Kinesiology Association and National Kinesiology Academy. One of eight senior academics charged with creating best practices for the study of kinesiology within U.S. universities and colleges. 2016-2018.

Elected, Executive Committee, National Academy of Kinesiology, 2016-2018.

Recent research and scholarship

Peer-reviewed publications: Journal articles 

*Denotes my role as senior researcher with study originating from my lab.

Hyde ET, Watson KB, Omura JD, Janz KF, Lee SM, Fulton JE, Carlson SA. Surveillance of Meeting the Youth Physical Activity Guideline: Impact of Including Vigorous-Intensity and Bone-Strengthening Activities [published online ahead of print, 2021 Oct 28]. Res Q Exerc Sport. 2021;1-6. doi:10.1080/02701367.2021.1914303

Chrisman SPD, Mendoza JA, Zhou C, Palermo TM, Gogue-Garcia T, Janz KF, Rivara FP. Pilot study of telehealth delivered rehabilitative exercise for youth with Concussion: The Mobile Subthreshold Exercise Program (MSTEP). Front Pediatr. 2021 May 28;9:645814. doi: 10.3389/fped.2021.645814. eCollection 2021. 

Julius BR, O'Shea AMJ, Francis SL, Janz KF, Laroche H. Leading by example: Association between mother and child objectively measured physical activity and sedentary behavior. Pediatr Exerc Sci. 2021 Apr 5;33(2):49-60. 

Saha PK, Oweis RR, Zhang X, Letuchy E, Eichenberger-Gilmore JM, Burns TL, Warren JJ, Janz KF, Torner JC, Snetselaar LG, Levy SM. Effects of fluoride intake on cortical and trabecular bone microstructure at early adulthood using multi-row detector computed tomography (MDCT). Bone. 2021 May;146:115882. doi: 10.1016/j.bone.2021.115882.

Kwon S, Letuchy EM, Levy SM, Janz KF*. Youth sports participation is more important among females than males for predicting physical activity in early adulthood: Iowa Bone Development Study. Int J Environ Res Public Health. 2021 Feb 2;18(3):1328. doi: 10.3390/ijerph18031328. 

Bay CP, Levy SM, Janz KF, Smith BJ, Shaffer JR, Marazita ML, Burns TL. Genome-wide association analysis of longitudinal bone mineral content data from the Iowa Bone Development Study. J Clin Densitom. 2021 Jan-Mar;24(1):44-54. doi: 10.1016/j.jocd.2019.09.005. 

Oh M, Zhang D, Whitaker KM, Letuchy EM, Janz KF*, Levy SM. Moderate-to-vigorous intensity physical activity trajectories during adolescence and young adulthood predict adiposity in young adulthood: The Iowa Bone Development Study. J Behav Med. 2021 Apr;44(2):231-240. doi: 10.1007/s10865-020-00190-x. 

Bernhardsen GP, Stensrud T, Hansen BH, Steene-Johannesen J, Kolle E, Nystad W, Anderssen SA, Hallal PC, Janz KF, Kriemler S, Andersen LB, Northstone K, Resaland GK, Sardinha LB, van Sluijs EMF, Ried-Larsen M, Ekelund U; International Children’s Accelerometry Database (ICAD) Collaborators. Birth weight, cardiometabolic risk factors and effect modification of physical activity in children and adolescents: pooled data from 12 international studies. Int J Obes (Lond). 2020 Oct;44(10):2052-2063. doi: 10.1038/s41366-020-0612-9. 

Pashkova A, Hartman JM, Letuchy EM, Janz KF*. Interscholastic athletics and bone strength: The Iowa Bone Development Study. J Strength Cond Res. 2020 May 25:10.1519/JSC.0000000000003646. doi: 10.1519/JSC.0000000000003646. Online ahead of print. 

Rowlands AV, Edwardson CL, Dawkins NP, Maylor BD, Metcalf KM, Janz KF. Physical activity for bone health: How much and/or how hard? Med Sci Sports Exerc. 2020 Nov;52(11):2331-2341. doi: 10.1249/MSS.0000000000002380. 

van Ekris E, Wijndaele K, Altenburg TM, Atkin AJ, Twisk J, Andersen LB, Janz KF, Froberg K, Northstone K, Page AS, Sardinha LB, van Sluijs EMF, Chinapaw M; International Children’s Accelerometry Database (ICAD) Collaborators. Tracking of total sedentary time and sedentary patterns in youth: a pooled analysis using the International Children's Accelerometry Database (ICAD). Int J Behav Nutr Phys Act. 2020 May 18;17(1):65. doi: 10.1186/s12966-020-00960-5. 

Metcalf KM, Letuchy EM, Levy SM, Janz KF*. An 8-year longitudinal analysis of physical activity and bone strength from adolescence to emerging adulthood: The Iowa Bone Development Study. Pediatr Exerc Sci. 2020 Feb 1;32(1):58-64. doi: 10.1123/pes.2019-0090. 

Rivara FP, Tennyson R, Mills B, Browd SR, Emery CA, Gioia G, Giza CC, Herring S, Janz KF, LaBella C, Valovich McLeod T, Meehan W, Patricios J; Four Corners Youth Consortium. Consensus statement on sports-related concussions in youth sports using a modified delphi approach. JAMA Pediatr. 2020 Jan 1;174(1):79-85. doi: 10.1001/jamapediatrics.2019.4006. PMID: 31710349 

Dias KI, White J, Jago R, Cardon G, Davey R, Janz KF, Pate RR, Puder JJ, Reilly JJ, Kipping R. International comparison of the levels and potential correlates of objectively measured sedentary time and physical activity among three-to-four-year-old children. Int J Environ Res Public Health. 2019 May 31;16(11):1929. doi: 10.3390/ije rph16111929. 

Pate RR, Hillman CH, Janz KF, Katzmarzyk PT, Powell KE, Torres A, Whitt-Glover MC; 2018 PHYSICAL ACTIVITY GUIDELINES ADVISORY COMMITTEE. Physical activity and health in children younger than 6 years: A systematic review. Med Sci Sports Exerc. 2019 Jun;51(6):1282-1291. 

Kraus WE, Powell KE, Haskell WL, Janz KF, Campbell WW, Jakicic JM, Troiano RP, Sprow K, Torres A, Piercy KL; 2018 PHYSICAL ACTIVITY GUIDELINES ADVISORY COMMITTEE. Physical activity, all-cause and cardiovascular mortality, and cardiovascular disease. Med Sci Sports Exerc. 2019 Jun;51(6):1270-1281.

Campbell WW, Kraus WE, Powell KE, Haskell WL, Janz KF, Jakicic JM, Troiano RP, Sprow K, Torres A, Piercy KL, Bartlett DB; 2018 PHYSICAL ACTIVITY GUIDELINES ADVISORY COMMITTEE. High-intensity interval training for cardiometabolic disease prevention. Med Sci Sports Exerc. 2019 Jun;51(6):1220-1226. 

Jakicic JM, Kraus WE, Powell KE, Campbell WW, Janz KF, Troiano RP, Sprow K, Torres A, Piercy KL; 2018 PHYSICAL ACTIVITY GUIDELINES ADVISORY COMMITTEE. Association between bout duration of physical activity and health: Systematic review. Med Sci Sports Exerc. 2019 Jun;51(6):1213-1219.

Kraus WE, Janz KF, Powell KE, Campbell WW, Jakicic JM, Troiano RP, Sprow K, Torres A, Piercy KL; 2018 PHYSICAL ACTIVITY GUIDELINES ADVISORY COMMITTEE. Daily step counts for measuring physical activity exposure and its relation to health. Med Sci Sports Exerc. 2019 Jun;51(6):1206-1212. 

Kwon S, Andersen LB, Grontved A, Kolle E, Cardon G, Davey R, Kriemler S, Northstone K, Page, AS, Puder JJ, Reilly JJ, Sarhinha L, van Sluijs EM, Janz KF. A closer look at the relationship among accelerometer-based physical activity metrics: ICAD pooled data. Int J Behav Nutr Phys Act. 2019 16:40. https://doi.org/10.1186/s12966-019-0801-x.

Eliakim A, Falk B, Armstrong N, Baptista F, Behm DG, Dror N, Faigenbaum AD, Janz KF, Jürimäe J, McGowan AL, Nemet D, Pianosi PT, Pontifex MB, Radom-Aizik S, Rowland T, Rowlands AV. Expert's Choice: 2018's most exciting research in the field of pediatric exercise science. Pediatr Exerc Sci. 2019 Feb 1;31(1):1-27. Epub 2019 Feb 13.

Ward RC, Janz KF*, Letuchy EM, Peterson C, Levy SM. Contribution of high school sport participation to young adult bone strength. Med Sci Sports Exerc. 2019 May;51(5):1064-1072. doi: 10.1249/MSS.0000000000001870. PMID: 30557192. 

Powell KE, King AC, Buchner DM, Campbell WW, DiPietro L, Erickson KI, Hillman CH, Jakicic JM, Janz KF, Katzmarzyk PT, Kraus WE, Macko RF, Marquez DX, McTiernan A, Pate RR, Pescatello LS, Whitt-Glover MC. The scientific foundation for the Physical Activity Guidelines for Americans, 2nd Edition. J Phys Act Health. 2018 Dec 17:1-11. doi: 10.1123/jpah.2018-0618. [Epub ahead of print] PMID: 30558473.

Baquero , Kava CM, Ashida S, Daniel-Ullo J, Laroche HH, Haines H, Bucklie R, Maldonado A, Garcia MC, Berto S, Sewell D, Novak N, Janz KF, Gates C, Parker EA. Active Ottumwa: adapting evidence-based recommendations to promote physical activity in a micropolitan new destination community. International Journal of Environmental Research and Public Health. 2018 May 4;15(5). pii: E917. doi: 10.3390/ijerph15050917.

Zymbal V, Baptista F, Letuchy EM, Janz KF*, Levy SM. Mediating effect of muscle on the relationship of physical activity and bone. Med Sci Sports Exerc. 2018 Aug 28. doi: 10.1249/MSS.0000000000001759. [Epub ahead of print].

Levy SM, Eichenberger-Gilmore JM, Warren JJ, Kavand G, Letuchy E, Broffitt B, Marshall TA, Burns TL, Janz KF, Pauley C, Torner JC, Phipps K. Associations of fluoride intake with children's cortical bone mineral and strength measures at age 11. J Public Health Dent. 2018 Aug 29. doi: 10.1111/jphd.12286. [Epub ahead of print].

Oweis RR, Levy SM, Eichenberger-Gilmore JM, Warren JJ, Burns TL, Janz KF, Torner JC, Saha PK, Letuchy E. Fluoride intake and cortical and trabecular bone characteristics in adolescents at age 17: A prospective cohort study.  Community Dent Oral Epidemiol. 2018 Jul 1. doi: 10.1111/cdoe.12373. [Epub ahead of print].

Tarp J, Child A, White T, Westgate K, Bugge A, Grøntved A, Wedderkopp N, Andersen LB, Cardon G, Davey R, Janz KF, Kriemler S, Northstone K, Page AS, Puder JJ, Reilly JJ, Sardinha LB, van Sluijs EMF, Ekelund U, Wijndaele K, Brage S; International Children’s Accelerometry Database (ICAD) Collaborators. Physical activity intensity, bout-duration, and cardiometabolic risk markers in children and adolescents. Int J Obes (Lond). 2018 Jul 13. doi: 10.1038/s41366-018-0152-8. [Epub ahead of print].

Janz KF, Baptista F. Bone Strength and Exercise During Youth-The Year That Was 2017. Pediatr Exerc Sci. 2018 Feb 1;30(1):28-31. doi: 10.1123/pes.2017-0295. Epub 2018 Feb 19.

Saint-Maurice PF, Laurson K, Welk GJ, Eisenmann J, Gracia-Marco L, Artero EG, Ortega F, Ruiz JR, Moreno LA, Vicente-Rodriguez G, Janz KF*. Grip strength cutpoints for youth based on a clinically relevant bone health outcome. Arch Osteoporos. 2018 Aug 27;13(1):92. doi: 10.1007/s11657-018-0502-0.

Metcalf KM, Baquero BI, Coronado Garcia ML, Francis SL, Janz KF, Laroche HH, Sewell DK. Calibration of the global physical activity questionnaire to accelerometry measured physical activity and sedentary behavior. BMC Public Health, 2018, 18(1), 412-421. 

Peer-reviewed publications: Chapters, reviews, government publications

The 2018 Physical Activity Guidelines Advisory Committee Scientific Report, Washington, DC:  U.S. Department of Health and Human Services, 2018. One of 17 committee members/writers. https://health.gov/paguidelines/second-edition/report.aspx.

Recent national press coverage of research and scholarship

Cooper Institute FitnessGram Blog. Playing Now to Protect Bones Later. Winter 2020.  https://fitnessgram.net/playing-now-to-protect-bones-later/

Nutrition Action Health Letter. A Body in Motion: What Matters and What’s Malarkey.  Caitlin Dow, Author. July/August 2019. 

Minnesota Public Radio: News Cut Hour: Physical Activity Guidelines. Interview with Kerri Miller. November 20, 2018. https://blogs.mprnews.org/newscut/2018/11/whats-on-mpr-news-11-19-18/

National Public Radio: HSS Releases New Physical Activity Guidelines.  Interview with Allison Aubrey. November 11, 2018. https://www.npr.org/sections/health-shots/2018/11/12/666744493/new-physi...

Research grants and contracts

Current formal consulting

The Interactive Effects of Physical Activity and Sedentary Behaviors during Childhood. Lurie Children’s Hospital of Chicago, Department of Pediatrics, R03, Soyang Kwon Principal Investigator. 2021-2022.

Recent invited research visits–national and international

Research Expert, Cooper China. Bone Health Across Lifespan. Nanjing and Beijing, China, January 7 to 16, 2019.

Department Visiting Scholar Lecture The Right Stuff: Physical Activity for Building Bones Strength, Department of Nutrition Science, Purdue University, February 21-22, 2018.

New picture of Kathy Janz
EdD, Community Health and Exercise Physiology