Synbiotic Supplementation in Cyclists

The goal of this randomized double-blinded clinical trial is to evaluate the potential beneficial effects of a synbiotic formulation on exercise performance in trained adult cyclists. The main questions it aims to answer are related to the Synbiotic effects on:

• Cycling performance
• Exercise metabolism
• Gastrointestinal health
• Immune system
• Body composition
• Fecal Short Chain Fatty Acids (SCFAs)
• Fecal microbiome composition

Participants will be recruited and, if consenting and eligible, will undergo the initial pre-testing phase for baseline assessment (4 on-site visits). Then, they will be randomized to receive the synbiotic or placebo and instructed to consume one sachet daily for 42 consecutive days. After 4-5 weeks of intervention (Day 33), post-testing phase will start, and participants will be asked to return to the site to perform post testing assessments (over 4 on-site visits). Study visits will occur as follows, V1 (Day -9), V2 (Day -6), V3 (Day -3), V4 (Day 0), V5 (Day 33), V6 (Day 36), V7 (Day 39), and V8 (Day 42).

Researchers will compare the assessed outcomes to baseline in each group and evaluate the difference between groups following the synbiotic consumption to highlight any statistically and clinically relevant observations.

Inclusion criteria

• Male or female between the ages of 18-45
• Currently cycling for at least 3 hours per week for the past 3 months
• Free of any contraindications to exercise and any medical condition that could interfere with or influence metabolic or cardiovascular responses to exercise
• Have a resting heart rate <100 bpm and resting systolic and diastolic blood pressures <160 mmHg and <90 mmHg, respectively.

Exclusion criteria

• Use of antibiotics or probiotic products within 4 weeks prior to study enrollment (note: participants will be eligible after a 2-week washout period)
• Current laxative use
• Are a smoker or use tobacco products
• Consume >21 units of alcohol per week
• Have donated blood in the previous 3 months
• Have a BMI ≥30kg/m2
• Are pregnant or lactating or planning to become pregnant for the duration of the study
• Are dieting for weight loss or are following a low carbohydrate diet
• Have participated in another clinical trial within the 30 days preceding study enrollment
• Are taking medications known to affect cardiovascular or metabolic responses to exercise
• Have a medical condition that could interfere with study intervention and assessment
• Have current musculoskeletal injuries that limit exercise capacity
• Are non-English speaking