What is already known
Advances in high-throughput sequencing have improved our understanding of the gut microbiota’s impact on athlete health and performance, but protocols are often inconsistent across studies.
What this research adds
The authors emphasize the need for standardized protocols in microbiota studies to ensure consistency in data collection and analysis. They also highlight best practices for stool sample collection, storage and analysis, while calling for approaches that combine metagenomics and metabolomics to understand the microbiota’s role in health and performance. Personalized nutrition based on individual microbiota profiles is also explored as a promising avenue for improving athlete health.
Conclusions
Standardizing microbiome analysis improves the quality and reliability of data, helping researchers to explore the gut microbiota’s impact on athletes and its relationship with health and performance.
Advances in high-throughput sequencing have improved our understanding of the gut microbiota’s impact on athletes’ health and performance, but protocols are often inconsistent across studies.
In a Perspective published in Cell Reports Medicine, Laura Mancin at the University of Padua, Italy, and her colleagues emphasize the need for standardized protocols in microbiota studies to ensure consistency in data collection and analysis. They also highlight best practices for stool sample collection, storage and analysis, while calling for approaches that combine metagenomics and metabolomics to understand the microbiota’s role in health and performance.
“Adherence to these standard operating procedures will accelerate the path toward improving the quality of data and ultimately our understanding of the influence of the gut microbiome in sport settings,” the authors say.
Research on the microbiota of athletes can be grouped into three types: microbiome epidemiology, which examines microbial variation over time and its association with health changes in athletes; randomized controlled trials, which assess causal relationships between dietary or lifestyle interventions and athletes’ health; longitudinal studies that use statistical methods to estimate causal effects of diet on the microbiota and health of athletes.
Controlling confounding factors and standardizing sample collection is essential to ensure robust findings. There is no consensus on the best method for collecting stool samples for microbiota analysis, but proper sample collection, transportation and preservation are key for maintaining the microbiota intact.
The ‘gold standard’ involves collecting fresh stool samples and freezing them immediately. However, for athletes, alternative methods such as dry swabs and scoop kits may be more practical, the authors say. To maintain sample integrity, specific procedures and equipment are recommended, including labeling the container, using gloves and homogenizing the sample.
Immediate freezing at -80°C is ideal, but if not feasible, samples should be stored at 4°C to minimize changes in microbial profiles, the authors say. Processing should occur within one hour or no later than 24 hours.
Standardized approaches
In longitudinal studies, samples should be analyzed at least three days after dietary changes to accurately assess microbiota responses. Standardizing the collection of multiple samples at each time point helps to reduce bias.
To obtain reliable results, it is also essential to standardize methods to analyze samples, for example using bioinformatics tools such as QIIME.
Although microbial DNA sequencing is widely used, it only indicates that bacteria are present, but not whether they’re alive or what metabolites they produce. Approaches that combine metagenomics and metabolomics are increasingly used. For example, studies have identified stable bacterial taxa alongside metabolite changes in athletes’ fecal samples.
This approach highlights the importance of considering both bacterial taxa and metabolite profiles in understanding athletic performance, the authors say.
Personalized nutrition
Research has shown that specific bacterial species in the gut are linked to various health markers and lifestyle factors. Host genetics contributes only about 5% to microbial composition, while a diet rich in plant-based foods positively influences the microbiota.
Personalized nutrition, which tailors dietary strategies to individual microbiota profiles, shows promise but requires validation through large studies, the authors say.
Standardizing microbiota analyses can make findings more reliable and facilitate comparisons across studies. By implementing standardized practices, researchers can better explore the relationships between gut microbes, health and performance in athletes, the authors conclude.
