Electroencephalographic findings of young adult males during prolonged unipedal orthostasis


  • Mayowa Adeniyi Department of Physiology, Federal University of Health Sciences, Otukpo, Benue State, Nigeria.
  • Oyesanmi Fabunmi School of Laboratory Medicine and Medical Science, KwaZulu‑Natal, Durban, South Africa.
  • Olugbemi Olaniyan Departments of Physiology and Microbiology, Edo State University Uzairue, Edo Sate, Nigeria.
  • Charles Adetunji Departments of Physiology and Microbiology, Edo State University Uzairue, Edo Sate, Nigeria.
  • Samuel Seriki Departments of Physiology and Microbiology, Edo State University Uzairue, Edo Sate, Nigeria.




Orthostasis, Unipedal, Electroencephalogram, exertional distress, rate of perceived exertion


Previous investigations have enumerated the effect of prolonged bipedal orthostasis on body functions. The study investigated the effect of prolonged unipedal orthostasis on electroencephalographical tracings in young adult males. Twenty apparently healthy adult males aged 19-23 years were recruited for the study. Cardiovascular parameters and anthropometric indices were measured prior to the experiment. Exertional distress and orthostatic tolerance time were evaluated using Borg scale (6-20) and stop watch respectively as previously reported. Orthostatic tolerance time was defined as the time interval between assumption of unipedal position and the first perception of distress. Statistical test was done using SPSS 23 and significant difference was accepted at P<0.05. Prolonged unipedal orthostasis was characterised by significant increases in rate of perceived exertion and orthostatic tolerance time when compared with baseline values. During prolonged unipedal orthostasis, the frequency and amplitude of beta wave decreased, while alpha wave frequency and amplitude increased and decreased respectively when compared with the baseline. When compared with left leg orthostasis, there was an increase in alpha wave frequency during right leg orthostasis. Furthermore, stronger correlation coefficients were found between EEG fatigue index and rate of perceived exertion, orthostatic tolerance time, systolic blood pressure and diastolic blood pressure during right leg orthostasis. The results of the study showed that prolonged orthostasis modulated electroencephalographic waves with right leg orthostasis characterised by increased alpha wave frequency and increased EEG fatigue index.


Adeniyi, M. (2022). Impacts of Environmental Stressors on Autonomic Nervous System. In Theodoros Aslanidis Editor. Autonomic Nervous System. IntechOpen. https://doi.org/10.5772/intechopen.101842

Adeniyi, M., Fabunmi, O., Okojie, A., Olorunnisola, O., Odetola, A., Olaniyan, T., & Seriki, A. (2020). Impact of night study frequency on sleep pattern, anthropometrical indices and peripheral oxygen saturation in age-matched nigerian female students prior to semester examination. International Journal of Biomedical Science, 16(3), 37–42.

Adeniyi, M., Olaniyan, O., Fabunmi, O., Okojie, A., Ogunlade, A., & Ajayi, O. (2022). Modulatory role of pre-exercise water ingestion on metabolic, cardiovascular and autonomic responses to prolonged exercise in young mildly active male. International Journal of Biomedical Science, 18 (2), 24–34.

Australian Academy of Science. Reading the brain. Last accessed 1/9/2021. https://www.science.org.au/curious/people-medicine/eeg

Barrett, K.E., Susan, M., Barman, S.B., & Heddwen, L.B. (2010). Ganong's Review of Medical Physiology (23rd edition). New York, MC graw Hills. 421, 391–427.

Black, K., Zafonte, R., Millis, S., Desantis, N., Harrison-Felix, C., Wood, D., & Mann, N. (2000). Sitting balance following brain injury: does it predict outcome? Brain Injury, 14(2), 141–152. https://doi.org/10.1080/026990500120808

Borg, G. (1998). Borg's Perceived Exertion and Pan Scales. Champaign, IL: Human Kinetics.

Claydon, V. E., Christoph, S., Lucy, J.N., Jens J., & Roger, H. (2006). Water drinking improves orthostatic tolerance in patients with posturally related syncope. Clin Science, 110, 343–352. https://doi.org/10.1042/CS20050279

Eoh, H. J., Chung, M. K., & Kim, S. H. (2005) Electroencephalographic study of drowsiness in simulated driving with sleep deprivation. International Journal of Industrial Ergonomics, 35(4), 307–320. https://doi.org/10.1016/j.ergon.2004.09.006

Grenon, S. M., Xiao, X., Hurwitz, S., Sheynberg, N., Kim, C., Seely, E. W., Cohen, R. J., & Williams, G. H. (2006). Why is orthostatic tolerance lower in women than in men? Renal and cardiovascular responses to simulated microgravity and the role of midodrine. Journal of Investigative Medicine, 54, 180–190. https://doi.org/10.2310/6650.2006.05064

Gunay, F. S. D., & Dokuzlar, O. (2021) Mechanisms of Orthostatic Tolerance and Age-Related Changes in Orthostatic Challenge. In: Isik A.T., Soysal P. (eds) Orthostatic Hypotension in Older Adults. Springer, Cham. https://doi.org/10.1007/978-3-030-62493-4_1

Jap, B. T., Lal, S., Fischer, P., & Bekiaris, E. (2009). Using EEG spectral components to assess algorithms for detecting fatigue. Expert Systems with Applications, 36(2), 2352–2359. https://doi.org/10.1016/j.eswa.2007.12.043

Jonsson, E., Seiger, A., & Hirschfeld, H. (2004). One-leg stance in healthy young and elderly adults: a measure of postural steadiness? Cloinical Biomechanics, 19(7), 688-94. https://doi.org/10.1016/j.clinbiomech.2004.04.002

Mellingsæter, M. R., Wyller, T. B., Ranhoff, A. H., & Wyller, V. B. (2015). Fit elderly men can also stand: orthostatic tolerance and autonomic cardiovascular control in elderly endurance athletes. Aging Clinical and Experimental Research, 27, 499–505. https://doi.org/10.1007/s40520-014-0303-2

Mizrahi, J., Groswasser, Z., Susak, Z., & Reider-Groswasser, I. (1989). Standing posture of craniocerebral injured patients: bi-lateral reactive force patterns. Clinical Physics and Physiological Measurement, 10, 25–37. https://doi.org/10.1088/0143-0815/10/1/003

Morinushi, T., Masumoto, Y., Kawasaki, H., & Takigawa, M. (2000). effect on electroencephalogram of chewing flavored gum. Psychiatry & Clinical Neuroscience, 54(6), 645–651. https://doi.org/10.1046/j.1440-1819.2000.00772.x

Niedermeyer, E., & da Silva, F. L. (2004). Electroencephalography: Basic Principles, Clinical Applications, and Related Fields. Lippincott Williams & Wilkins, ISBN 978-0-7817-5126-1.

Olatunji, L. A., Aaron, A. O., Michael, O. S., & Oyeyipo, I. P. (2011). Water ingestion affects orthostatic challenge-induced blood pressure and heart rate responses in young healthy subjects: gender implications. Nigerian Journal of Physiological Sciences, 26, 011–018.

Oni, T. J., & Adeniyi, M. J. (2017). Postural Difference in Expiratory Rate among Female Sanitary Workers and its Relationship with Blood Pressure and Anthropometric Indices. Biomedical Journal of Scientific & Technical Research, 1(2), 311–315. http://doi.org/10.26717/BJSTR.2017.01.000182

Platts, S. H., Bairey Merz, C. N., Barr, Y., Fu, Q., Gulati, M., Hughson, R., Levine, B. D., Mehran, R., Stachenfeld, N., & Wenger, N. K. (2014). Effects of sex and gender on adaptation to space: cardiovascular alterations. Journal of Womens Health, 23(11), 950–955. https://doi.org/10.1089/jwh.2014.4912

Schroeder, C., Victoria, E. B., Lucy, J. N., Friedrich, C. L., Jens, T., Jens, J., & Roger, H. (2002). Water Drinking Acutely Improves Orthostatic Tolerance in Healthy Subjects. Circulation, 106, 2806–2811. https://doi.org/10.1161/01.CIR.0000038921.64575.D0

Springer, B. A., Marin, R., Cyhan, T., Roberts, H., & Gill, N. W. (2007). Normative Values for the Unipedal Stance Test with Eyes Open and Closed. Journal of Geriatric Physical Therapy, 30(1), 8–15.

Stern, J. M. (2005). Atlas of EEG Patterns. Lippincott Williams & Wilkins, Philadelphia.

Usman, T. O., Olatunji, V. A., & Olatunji, L. A. (2015). Ingestion of glucose and Vitamin C affects orthostatic stress-induced cardiovascular responses in young men. Nigerian Journal of Experimental and Clinical Biosciences, 3, 92–98. https://doi.org/10.4103/njecp.njecp_26_15

Young, T. M., & Mathias, C. J. (2004). The effects of water ingestion on orthostatic hypotension in two groups of chronic autonomic failure: multiple system atrophy and pure autonomic failure. Journal of Neurology, Neurosurgery & Psychiatry, 75, 1737–1741. https://doi.org/10.1136/jnnp.2004.038471




How to Cite

Adeniyi, M., Fabunmi, O., Olaniyan, O., Adetunji, C. and Seriki, S. (2023) “Electroencephalographic findings of young adult males during prolonged unipedal orthostasis”, Neuroscience Research Notes, 6(2), pp. 177.1–177.8. doi: 10.31117/neuroscirn.v6i2.177.