Skip to main content
Log in

Brain oxygenation declines in elite Kenyan runners during a maximal interval training session

  • Original Article
  • Published:
European Journal of Applied Physiology Aims and scope Submit manuscript



The purpose of this study was to characterise the cerebral oxygenation (Cox) response during a high-intensity interval training session in Kenyan runners, and to examine any relationship with running performance.


15 Kenyan runners completed a 5-km time trial (TT) and a Fatigue Training Test on a treadmill (repeated running bouts of 1-km at a pace 5% faster than their mean 5-km TT pace with a 30-s recovery until exhaustion). Changes in Cox were monitored via near-infrared spectroscopy through concentration changes in oxy- and deoxy-haemoglobin (Δ[O2Hb] and Δ[HHb]), tissue oxygenation index (TOI), and total hemoglobin index (nTHI).


The number of 1-km repetitions achieved by the participants was 5.5 ± 1.2 repetitions at a mean pace of 20.5 ± 0.7 km h−1. Δ[O2Hb] measured at the end of each running repetition declined progressively over the course of the trial (p = 0.01, ES = 4.59). Δ[HHb] increased during each running bout until the end of the Fatigue Training Test (p < 0.001; ES = 6.0). TOI decreased significantly from the beginning of the test (p = 0.013, ES = 1.83), whereas nTHI remained stable (ES = 0.08). The Cox decline in the Fatigue Training Test was negatively correlated with the speed at which the test was completed (p = 0.017; r = −0.61), suggesting that the best performers were able to defend their Cox better than those of lower running ability.


In conclusion, this study suggests that elite Kenyan runners cannot defend cerebral oxygenation when forced to exercise to their physiological limits. This emphasises the critical importance of pacing in their racing success.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2

Similar content being viewed by others



Analysis of variance


Cerebral oxygenation


Coefficient of variation


Effect size


Functional near-infrared spectroscopy


High-intensity interval training


Heart rate

n :

Participant number


Total hemoglobin index

PaCO2 :

CO2 partial pressure


Standard deviation

SpO2 :

Arterial oxygen saturation


Tissue oxygenation index


Time trial

VO2max :

Maximum oxygen uptake


Deoxy-haemoglobin changes


Oxy-hemoglobin changes


  • Amann M, Romer LM, Subudhi AW, Pegelow DF, Dempsey JA (2007) Severity of arterial hypoxaemia affects the relative contributions of peripheral muscle fatigue to exercise performance in healthy humans. J Physiol 581:389–403

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Baker J, Horton S (2003) East African running dominance revisited: a role for stereotype threat? Br J Sports Med 37:553–555

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Bhambhani Y, Malik R, Mookerjee S (2007) Cerebral oxygenation declines at exercise intensities above the respiratory compensation threshold. Respir Physiol Neurobiol 156:196–202

    Article  PubMed  Google Scholar 

  • Billat V, Lepretre PM, Heugas AM, Laurence MH, Salim D, Koralsztein JP (2003) Training and bioenergetic characteristics in elite male and female Kenyan runners. Med Sci Sports Exerc 35(2):297–304

    Article  PubMed  Google Scholar 

  • Billaut F, Davis JM, Smith KJ, Marino FE, Noakes TD (2010) Cerebral oxygenation decreases but does not impair performance during self-paced, strenuous exercise. Acta Physiol (Oxf) 198:477–486

    Article  CAS  Google Scholar 

  • Carrillo AE, Koutedakis Y, Flouris AD (2011) Early life mammalian biology and later life physical performance: maximizing physiological adaptation. Br J Sports Med 45:1000–1001

    Article  PubMed  Google Scholar 

  • Cohen J (1988) Statistical power analysis for the behavioural sciences. Erlbaum, Mahwah

    Google Scholar 

  • Colier WN, Quaresima V, Oeseburg B, Ferrari M (1999) Human motor-cortex oxygenation changes induced by cyclic coupled movements of hand and foot. Exp Brain Res 129:457–461

    Article  CAS  PubMed  Google Scholar 

  • Foster GE, Koehle MS, Dominelli PB, Mwangi FM, Onywera VO, Boit MK, Tremblay JC, Boit C, Sheel AW (2014) Pulmonary mechanics and gas exchange during exercise in Kenyan distance runners. Med Sci Sports Exerc 46:702–710

    Article  PubMed  Google Scholar 

  • Gassmann NN, van Elteren HA, Goos TG, Morales CR, Rivera-Ch M, Martin DS, Cabala Peralta P, Passano Del Carpio A, Aranibar Machaca S, Huicho L, Reiss IK, Gassmann M, de Jonge RC (2016) Pregnancy at high altitude in the Andes leads to increased total vessel density in healthy newborns. J Appl Physiol 121:709–715

    Article  PubMed  Google Scholar 

  • Gibson AR, Ojiambo R, Konstabel K, Lieberman DE, Reilly JJ, Speakman JR, Pitsiladis YP (2013) Aerobic capacity, activity levels and daily energy expenditure in male and female adolescents of the Kenyan Nandi Sub-Group. PLoS One 8:e66552

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Hirasawa A, Yanagisawa S, Tanaka N, Funane T, Kiguchi M, Sørensen H, Secher NH, Ogoh S (2015) Influence of skin blood flow and source-detector distance on near-infrared spectroscopy-determined cerebral oxygenation in humans. Clin Physiol Funct Imaging 35:237–244

    Article  CAS  PubMed  Google Scholar 

  • Hopkins WG, Marshall SW, Batterham AM, Hanin J (2009) Progressive statistics for studies in sports medicine and exercise science. Med Sci Sports Exerc 41:3–13

    Article  PubMed  Google Scholar 

  • Ide K, Horn A, Secher NH (1999) Cerebral metabolic response to submaximal exercise. J Appl Physiol 87:1604–1608

    CAS  PubMed  Google Scholar 

  • Julian CG, Vargas E, Armaza JF, Wilson MJ, Niermeyer S, Moore LG (2007) High-altitude ancestry protects against hypoxia-associated reductions in fetal growth. Arch Dis Child Fetal Neonatal Ed 92:F372–F377

    Article  PubMed  PubMed Central  Google Scholar 

  • Julian CG, Wilson MJ, Moore LG (2009) Evolutionary adaptation to high altitude: a view from in utero. Am J Hum Biol 21:614–622

    Article  PubMed  PubMed Central  Google Scholar 

  • Kunimasa Y, Sano K, Oda T, Nicol C, Komi PV, Locatelli E, Ito A, Ishikawa M (2014) Specific muscle-tendon architecture in elite Kenyan distance runners. Scand J Med Sci Sports 24:e269–e274

    Article  CAS  PubMed  Google Scholar 

  • Manners J (1997) Kenya’s running tribe. Sports Hist 17:14–27

    Article  Google Scholar 

  • Mattocks C, Deere K, Leary S, Ness A, Tilling K, Blair SN, Riddoch C (2008) Early life determinants of physical activity in 11 to 12 year olds: cohort study. Br J Sports Med 42:721–724

    PubMed  Google Scholar 

  • Nielsen HB, Boushel R, Madsen P, Secher NH (1999) Cerebral desaturation during exercise reversed by O2 supplementation. Am J Physiol 277:H1045–H1052

    CAS  PubMed  Google Scholar 

  • Onywera VO, Scott RA, Boit MK, Pitsiladis YP (2006) Demographic characteristics of elite Kenyan endurance runners. J Sports Sci 24:415–422

    Article  PubMed  Google Scholar 

  • Pearce WJ, Butler SM, Abrassart JM, Williams JM (2011) Fetal cerebral oxygenation: the homeostatic role of vascular adaptations to hypoxic stress. Adv Exp Med Biol 701:225–232

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Perrey S (2008) Non-invasive NIR spectroscopy of human brain function during exercise. Methods 45:289–299

    Article  CAS  PubMed  Google Scholar 

  • Rasmussen P, Nielsen J, Overgaard M, Krogh-Madsen R, Gjedde A, Secher NH, Petersen NC (2010) Reduced muscle activation during exercise related to brain oxygenation and metabolism in humans. J Physiol 588:1985–1995

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Rogers RL, Meyer JS, Mortel KF (1990) After reaching retirement age physical activity sustains cerebral perfusion and cognition. J Am Geriatr Soc 38:123–128

    Article  CAS  PubMed  Google Scholar 

  • Romer LM, Haverkamp HC, Lovering AT, Pegelow DF, Dempsey JA (2006) Effect of exercise-induced arterial hypoxemia on quadriceps muscle fatigue in healthy humans. Am J Physiol Regul Integr Comp Physiol 290:R365–R375

    Article  CAS  PubMed  Google Scholar 

  • Rupp T, Perrey S (2008) Prefrontal cortex oxygenation and neuromuscular responses to exhaustive exercise. Eur J Appl Physiol 102:153–163

    PubMed  Google Scholar 

  • Saltin B, Kim CK, Terrados N, Larsen H, Svedenhag J, Rolf CJ (1995) Morphology, enzyme activities and buffer capacity in leg muscles of Kenyan and Scandinavian runners. Scand J Med Sci Sport 5:222–230

    Article  CAS  Google Scholar 

  • Sano K, Ishikawa M, Nobue A, Danno Y, Akiyama M, Oda T, Ito A, Hoffrén M, Nicol C, Locatelli E, Komi PV (2013) Muscle-tendon interaction and EMG profiles of world class endurance runners during hopping. Eur J Appl Physiol 113:1395–1403

    Article  CAS  PubMed  Google Scholar 

  • Sano K, Nicol C, Akiyama M, Kunimasa Y, Oda T, Ito A, Locatelli E, Komi PV, Ishikawa M (2015) Can measures of muscle-tendon interaction improve our understanding of the superiority of Kenyan endurance runners? Eur J Appl Physiol 115:849–859

    Article  PubMed  Google Scholar 

  • Santos-Concejero J, Tucker R, Myburgh KH, Essen-Gustavsson B, Kohn TA (2014) Greater performance impairment of black runners than white runners when running in hypoxia. Int J Sports Med 35:809–816

    Article  CAS  PubMed  Google Scholar 

  • Santos-Concejero J, Billaut F, Grobler L, Oliván J, Noakes TD, Tucker R (2015) Maintained cerebral oxygenation during maximal self-paced exercise in elite Kenyan runners. J Appl Physiol 118:156–162

    Article  CAS  PubMed  Google Scholar 

  • Santos-Concejero J, Tam N, Coetzee DR, Oliván J, Noakes TD, Tucker R (2017) Are gait characteristics and ground reaction forces related to energy cost of running in elite Kenyan runners? J Sports Sci 35:531–538

    CAS  PubMed  Google Scholar 

  • Seifert T, Rasmussen P, Secher NH, Nielsen HB (2009) Cerebral oxygenation decreases during exercise in humans with beta-adrenergic blockade. Acta Physiol (Oxf) 196:295–302

    Article  CAS  Google Scholar 

  • Subudhi AW, Lorenz MC, Fulco CS, Roach RC (2008) Cerebrovascular responses to incremental exercise during hypobaric hypoxia: effect of oxygenation on maximal performance. Am J Physiol Heart Circ Physiol 294:H164–H171

    Article  CAS  PubMed  Google Scholar 

  • Subudhi AW, Miramon BR, Granger ME, Roach RC (2009) Frontal and motor cortex oxygenation during maximal exercise in normoxia and hypoxia. J Appl Physiol 106:1153–1158

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Suzuki S, Takasaki S, Ozaki T, Kobayashi Y (1999) A tissue oxygenation monitor using NIR spatially resolved spectroscopy. Proc SPIE 3579:144–145

    Google Scholar 

  • Tam N, Santos-Concejero J, Coetzee DR, Noakes TD, Tucker R (2017) Muscle co-activation and its influence on running performance and risk of injury in elite Kenyan runners. J Sports Sci 35:175–181

    Article  PubMed  Google Scholar 

  • Tanner RK, Fuller KL, Ross ML (2010) Evaluation of three portable blood analysers: Lactate Pro, Lactate Scout and Lactate Plus. Eur J Appl Physiol 109:551–559

    Article  CAS  PubMed  Google Scholar 

  • Tucker R, Noakes TD (2009) The physiological regulation of pacing strategy during exercise: a critical review. Br J Sports Med 43:e1

    Article  CAS  PubMed  Google Scholar 

  • Tucker R, Santos-Concejero J, Collins M (2013) The genetic basis for elite running performance. Br J Sports Med 47:545–549

    Article  PubMed  Google Scholar 

  • Tucker R, Onywera VO, Santos-Concejero J (2015) Analysis of the Kenyan distance-running phenomenon. Int J Sports Physiol Perform 10:285–291

    Article  PubMed  Google Scholar 

  • Wassenaar EB, Van den Brand JG (2005) Reliability of near-infrared spectroscopy in people with dark skin pigmentation. J Clin Monit Comput 19:195–199

    Article  CAS  PubMed  Google Scholar 

  • Wilber RL, Pitsiladis YP (2012) Kenyan and Ethiopian distance runners: what makes them so good? Int J Sports Physiol Perform 7:92–102

    Article  PubMed  Google Scholar 

Download references


This study was supported by a National Research Foundation Grant (CPR20110704000020012) and by a Faculty of Health Sciences Postdoctoral Research Fellowship (University of Cape Town) to J. Santos-Concejero.

Author information

Authors and Affiliations


Corresponding author

Correspondence to Jordan Santos-Concejero.

Ethics declarations

Conflict of interest

The authors report no conflict of interest.

Additional information

Communicated by Peter Krustrup.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Santos-Concejero, J., Billaut, F., Grobler, L. et al. Brain oxygenation declines in elite Kenyan runners during a maximal interval training session. Eur J Appl Physiol 117, 1017–1024 (2017).

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: