Delivery mode, diet and antibiotic exposure initially influence the gut microbiota, with adult-like microbial communities emerging one to three years after birth.
Researchers at the University of Colorado at Boulder recently reported that early life exercise in rats increases beneficial gut bacteria involved in psychological and metabolic health. In their latest review published in Immunology and Cell Biology they emphasize the life-long effects.
The immature gut may be more sensitive to environmental influences and provide a "window of opportunity for better health", they said.
Author Monika Fleshner told NutraIngredients: "There are many studies to date that establish that many of the fundamental properties of the gut microbiota in rodents is applicable to humans. The interesting plasticity of a young community structure, for example, is one area of commonality.
"The ability of a young microbiota to robustly respond to environmental stimuli, such as diet and exercise, is likely the primary reason that early life exercise, compared to adult exercise, produces more profound alterations in gut the microbiota."
Some of the health benefits of exercise may be due to it inducing adaptations in gut microbiota. These adaptations can favourably impact the host's immune system, fat accumulation and brain plasticity and function.
The research showed the impact was greater if exercise was started in childhood rather than adulthood.
Although the mechanisms are not fully understood, early exercise produces more robust and longer-lasting health benefits throughout the lifespan, they said.
The review discussed dramatic changes to the brain and neurotransmission during childhood and adolescent development, saying it was possible initiating childhood exercise may be protective against stress-induced disorders such as depression and anxiety. Studies have shown that probiotics and prebiotics have a beneficial effect on anxiety and behaviour.
The optimum age to start exercise has yet to be pinpointed, however.
"We have a great deal of pre-clinical work to better establish the specific mechanisms for these effects and to discover ways of increasing plasticity in the adult microbiota. The scientific community is very excited about this area of research and human research into these questions are also ongoing," Fleshner told us.
Source: Immunology and Cell Biology
Published online ahead of print, http://dx.doi.org/10.1038/icb.2015.113
“Early-life exercise may promote lasting brain and metabolic health through gut bacterial metabolites”
Authors: A. Mika and M. Fleshner