Dynamics of Gut Microbiota and Short-Chain Fatty Acids during a Cycling Grand Tour Are Related to Exercise Performance and Modulated by Dietary Intake.

Background: Regular exercise has been described to modify both the diversity and the relative abundance of certain bacterial taxa. To our knowledge, the effect of a cycling stage race, which entails extreme physiological and metabolic demands, on the gut microbiota composition and its metabolic activity has not been analysed.

Objective: The aim of this cohort study was to analyse the dynamics of faecal microbiota composition and short-chain fatty acids (SCFAs) content of professional cyclists over a Grand Tour and their relationship with performance and dietary intake.

Frequent participation in high volume exercise throughout life is associated with a more differentiated adaptive immune response.

Exercise induces changes in the immune system depending on its intensity and duration. For example, transient states of immunodepression can be induced after acute intense physical activity whereas beneficial anti-inflammatory effects of moderate chronic exercise on many diseases and longevity have been described. To study the impact of high volume exercise over a lifetime on aspects of immunity we compared immunological features of 27 young and 12 elderly athletes with 30 young and 26 elderly non-athletes stratified by their CMV serostatus.

Exercise intensity during off-road cycling competitions.

Purpose: This study was designed to quantify and describe the intensity profile of cross-country mountain-biking races using heart rate (HR) recorded during competitions.

Methods: Nine mountain bikers participated in four cross-country circuit races of international and national levels. Each cyclist was tested before the competitions to determine lactate threshold (LT), the onset of blood lactate accumulation (OBLA4), and the relationship between percentage of maximum HR and percentage of VO(2max).

Diagnosing external iliac endofibrosis by postexercise ankle to arm index in cyclists.

Purpose: The aim of this study was to determine a noninvasive method of evaluating external iliac endofibrosis in cyclists.

Methods: Eighteen highly trained male cyclists were divided into two groups: a pathology group (PG; 3 professional and 4 elite) and a control group (CG; 6 professional and 5 elite). Mean age was 26 +/- 6.