Saurabh Thosar Lab

 Saurabh Thosar Ph.D., M.S., OTR/L
Saurabh Thosar Ph.D., M.S., OTR/L

About Dr. Thosar

Dr Saurabh Thosar received a B.O.Th in Occupational Therapy from Maharashtra University of Health Science in India, an M.S. in Movement Sciences from the Univ. of Illinois Chicago, and a Ph.D. in Human Performance (Physiology) from Indiana Univ. Bloomington. He is a certified clinical exercise specialist and licensed occupational therapist. Saurabh joined Dr. Shea's group as a postdoctoral fellow in January 2014 and has received a fellowship from the National Space Biomedical Research Institute, an early clinical investigator award from the Medical Research Foundation of Oregon, and a postdoctoral fellowship from the National Institutes of Health.  Dr. Thosar studies the interactions between sleep, circadian rhythms and physical inactivity/activity as they relate to cardiovascular disease; and the development of chronotherapeutic countermeasures to cardiovascular risks in vulnerable populations. 

Research interests

We plan to study the effects of pervasive occupational stressors namely sedentary behavior and shift work on the cardiometabolic system in vulnerable populations. Our long term goal is to develop sustainable countermeasures (behavioral: physical activity; pharmacological: chronotherapy) to mitigate cardiovascular risk in humans.

Uninterrupted prolonged sitting impairs vascular endothelial function

Uninterrupted prolonged sitting impairs vascular endothelial function measured non-invasively as flow mediated dilation (FMD; red solid line). Short 5-min breaks of light intensity physical activity prevent this impairment (black dotted line). From: Thosar et al, 2015.


  • Thosar, S. S., Berman, A. M., Herzig, M. X., Roberts, S. A., Lasarev, M. R., Shea, S. A. (2018). Morning impairment
  • in vascular function is unrelated to overnight sleep or the inactivity that accompanies sleep. American Journal of
  • Physiology-Regulatory, Integrative and Comparative Physiology. Accepted for publication.
  • Thosar, S. S., Herzig, M. X., Roberts, S. A., Berman, A. M., Clemons, N. A., McHill, A. W., Bowles, N. P., Morimoto,
  • M., Butler, M. P., Emens, J. S., Shea, S. A. (2018). Lowest perceived exertion in the late morning due to effects of the
  • endogenous circadian system. Epub ahead of print pii: bjsports-2018-099148. PMID: 29475839
  • Thosar, S. S., Butler, M. P., Shea, S.A. (2018). Role of the circadian system in cardiovascular disease: a double-edged
  • sword. Journal of Clinical Investigation, 128(6):2157-2167. PMID: 29856365
  • Thosar, S. S., Niederhausen, M., Lapidus, J., et al. (2017). Self-regulated use of a wearable activity sensor is not
  • associated with improvements in physical activity, cardiometabolic risk or subjective health status British Journal of
  • Sports Medicine. Epub ahead of print. doi: 10.1136/bjsports-2017-098512. PMID: 29222201
  • Parthasarathy, S., Carskadon, M. A., Jean-Louis, G., Owens, J., Bramoweth, A., Combs, D., Hale, L., Harrison, E.,
  • Hart, C. N., Hasler, B. P., Honaker, S. M., Hertenstein, E., Kuna, S., Kushida, C., Levenson, J. C., Murray, C., Pack, A.
  • I., Pillai, V., Pruiksma, K., Seixas, A., Strollo, P., Thosar, S. S., Williams, N., Buysse, D. (2016). Implementation of
  • Sleep and Circadian Science: Recommendations from the Sleep Research Society and National Institutes of Health
  • Workshop. SLEEP. 39(12): 2061–2075. PMID: 28201795
  • Berman, Alec M., Thosar, S. S. & Shea, S. A. (2016). Are we underestimating the lifelong benefits of therapy for
  • obstructive sleep apnea? Nature and Science of Sleep. 8: 87. PMID: 27051325
  • Thosar S. S., Wiggins, C. C., Shea, S. A, Wallace, J. P. (2015). Brachial artery endothelial function is stable across the
  • morning hours in young men. Cardiovascular Ultrasound. 13: 42. PMID: 26438100
  • Thosar, S.S., Bielko, S., Mather, K., Johnston, D., Wallace, J. (2015). Effect of prolonged sitting and breaks in sitting
  • time on endothelial function. Medicine and Science in Sports and Exercise. 47(4):843-849. PMID: 25137367
  • Thosar, S. S., Bielko, S. L., Wiggins, C. C., Klaunig, J. E., Mather, K. J., Wallace, J. P. (2015). Antioxidant Vitamin C
  • prevents the decline in endothelial function during sitting. Medical Science Monitor. 21: 1015–1021. PMID: 25848890
  • Thosar, S. S., Bielko, S. L., Wiggins, C. C., Wallace, J. P. (2014). Differences in brachial and femoral artery responses
    to prolonged sitting. Cardiovascular Ultrasound. 12:50. PMID 25512175