Early life mammalian biology and later life physical performance: maximising physiological adaptation

Abstract

The malleability of mammalian biology during early life, which carries considerable weight throughout the course of the lifespan, may contribute to the creation of a human phenotype ideal for prime physical performance. In this article, the authors consider the East African cohort of exceptional athletes that dominate marathon performance. Since entering international marathon competition in 1960, East Africans have competed at the front of the pack and now hold the top 10 men's marathon times. The authors present lines of evidence supporting that exposure to factors such as altitude and early metabolic adjustments that are inherent in East African early life exert a strong influence in later life physical performance and may collide with a genetic advantage to induce biological changes that allow for a more robust biological response to training in later life.

Maintained cerebral oxygenation during maximal self-paced exercise in elite Kenyan runners

“…A shared characteristic of the elite Kalenjin distance runners is that they are born and raised at an elevation of ϳ2,000 to 2,500 m. This early-life factor has been proposed to influence fetal growth, particularly in individuals of multigenerational highaltitude ancestry, which is the case for Kalenjin runners. This may in turn have implications for later-life endurance performance, including a reduction in the degree to which arterial desaturation occurs during heavy exercise in elite performers (5). Other early-life factors shared by Kalenjin runners, such as high levels of physical activity during their childhood, may provide further explanation for the Kenyan athletic success (5,9,23).…”

“…This may in turn have implications for later-life endurance performance, including a reduction in the degree to which arterial desaturation occurs during heavy exercise in elite performers (5). Other early-life factors shared by Kalenjin runners, such as high levels of physical activity during their childhood, may provide further explanation for the Kenyan athletic success (5,9,23). The effects of these considerable levels of physical activity during childhood have been confirmed and include increased left ventricular mass, neuronal growth, and augmented cerebral circulation through increased vascularization of the brain (19,28).…”

Greater Performance Impairment of Black Runners than White Runners when Running in Hypoxia

“…As many of the best black runners, especially those from Kenya and Ethiopia, come from high-altitude areas [ 9 , 25 , 30 ] , studies investigating the physiological responses to hypoxia in these populations would have been infl uenced by early life factors [ 5 ] , making it diffi cult to clarIntroduction ▼ Numerous research studies have examined factors that might account for the superiority of black endurance runners [ 2 , 7 , 20 , 34 , 36 ] . However, the explanation for their disproportionate success remains unclear and debated within the literature.…”

Habitual Heat Exposure and Acclimatization Associated with Athletic Performance in the Multistage Marathon des Sables

“…While the physiological impact of age and sex during exercise in hot environments is well established (Flouris & Piantoni, 2015;Stapleton et al, 2014Stapleton et al, , 2015, the impact of nationality and, hence, the habitual experience with heat stress remains unclear. Several case reports in the literature suggest that athletes' origin may impact athletic performance (Carrillo, Koutedakis, & Flouris, 2011;Lucia et al, 2006;Onywera, Scott, Boit, & Pitsiladis, 2006;Scott & Pitsiladis, 2007). However, the available genetic studies do not confirm that a unique genetic makeup can explain this relationship (Scott & Pitsiladis, 2007).…”