Comparative Analysis of Gut Microbiota in Collegiate Swimmers Following Changes in Exercise

Exercise can
influence gut microbial community structure and diversity; however, the
temporal dynamics of this association have rarely been explored. Here we
characterized fecal microbiota in response to short term changes in training
volume. Fecal samples, body composition, and training logs were collected from
Division I NCAA collegiate swimmers during peak training through their
in-season taper in 2016 (n = 9) and 2017 (n = 7), capturing a systematic
reduction in training volume near the conclusion of their athletic season.
Fecal microbiota were characterized using 16S rRNA V4 amplicon sequencing and
multivariate statistical analysis, Spearman rank correlations, and random
forest models. Peak training volume, measured as swimming distance, decreased
significantly during the study period from 32.6 ± 4.8 km/wk to 11.3 ± 8.1 km/wk
(ANOVA, p < 0.05); however, body composition showed no significant
changes. Coinciding with the decrease
in training volume, the microbial community structure showed a significant decrease
in overall microbial diversity, a decrease in microbial community structural
similarity, and a decrease in the proportion of the bacterial genera <i>Faecalibacterium</i> and <i>Coprococcu</i>s. Together these data
suggested changes in training volume significantly influence the gut
microbiome; future research will establish whether these changes are associated
with energy balance or nutrient intake.

运动可影响肠道微生物群落结构与多样性，但二者间关联的时间动态特征却鲜有研究探索。本研究针对训练量短期变化对粪便微生物群的影响展开特征解析。我们于2016年（n=9）与2017年（n=7），在NCAA第一级别（Division I NCAA）大学游泳运动员从巅峰训练期过渡至赛季内减量周期的过程中，采集其粪便样本、身体成分数据及训练日志，完整捕捉了运动赛季临近尾声时训练量的系统性下降过程。本研究采用16S rRNA V4区扩增子测序、多元统计分析、斯皮尔曼（Spearman）秩相关分析以及随机森林模型，对粪便微生物群进行特征解析。以游泳距离为衡量标准的巅峰训练量在本研究期间显著下降，从32.6±4.8 km/周降至11.3±8.1 km/周（方差分析ANOVA，p<0.05）；但受试者的身体成分未出现显著变化。伴随训练量下降，微生物群落整体多样性显著降低，群落结构相似性有所下降，且粪杆菌属（Faecalibacterium）与粪球菌属（Coprococcus）的相对丰度亦出现降低。综上，本研究数据表明训练量变化可显著影响肠道微生物组；未来研究可进一步明确此类变化是否与能量平衡或营养摄入相关。