At the Olympics, a simple cold can make the difference between gold and elimination. Top athletes train for years, but during the Games they are at extra risk: travel, stress, intense strain and sleep deprivation weaken the immune system. The key to protection is often not in a vaccination or drug, but in the crosstalk between gut and immune system.

Why athletes are more susceptible to infections

• High training load → temporary decline in immune function(open window effect).
• Travel and jet lag → disrupt circadian rhythms and decrease mucosal resistance.
• Stress and tension → increase cortisol and decrease immune activity.

Sports Immunology Journal (2021) confirms that athletes leading up to the Games are up to 2× more likely to have respiratory tract infections than non-athletes.

Microbiome and immune function

About 70% of all immune cells are located in the gut. The microbiome constantly trains these cells:

• SCFAs stimulate regulatory T cells → control inflammation.
• Diverse microbiome = higher resistance to pathogens.
• Dysbiosis = more leaky gut + increased susceptibility to infections.

Cell Host & Microbe (2015) showed that a balanced microbiome protects not only intestines but also lungs and skin through the gut-lung and gut-skin axes.

DNA and susceptibility to infections

• TLR genes → determine how strongly your immune system responds to microbes.
• IL-6 variants → influence inflammation susceptibility after heavy exercise.
• FUT2-secretor status → non-secretors often have less Bifidobacterium and a lower mucosal barrier.

Practical biohacks for Olympic athletes

1. Immune-Resilience Index
   - My InnerSelfie measures DNA + microbiome diversity + metabolites (such as SCFAs and inflammation markers).
2. Personalized nutrition
   - Not blindly taking probiotics, but encouraging specific bacterial profiles that fit the athlete's DNA.
3. Circadian immune support
   - Aligning diet, exercise and sleep with day-night rhythms → reduced infection risk.
4. Stress-buffering
   - Multi-omics reveals who is more susceptible to stress-related immunosuppression so that interventions can be targeted.
5. Preventive monitoring
   - Ongoing microbiome and metabolite testing detects subtle drops in immune resistance before they cause symptoms.

Why My InnerSelfie is unique in infection prevention

• DNA → shows predisposition to immune responses and susceptibility.
• Microbiome → reveals whether the gut barrier is robust or fragile.
• Metabolites → measure inflammatory status real-time.
• Result → personalized plan that reduces infection risks during the Games.

Key insights

• Olympic athletes are at increased risk of infection due to training, stress and travel.
• The microbiome determines 70% of immune resistance.
• DNA and metabolites explain individual differences in susceptibility.
• My InnerSelfie enables preventive infection control with multi-omics.

Scientific references

• Wlodarska M, Kostic AD, Xavier RJ. An integrative view of microbiome-host interactions in immune defense. Cell Host & Microbe. 2015.
• Clauss M, Gérard P, Mosca A, Leclerc M. Exercise and gut microbiome in performance. Front Nutr. 2021.
• Sports Immunology Journal. (2021). Upper respiratory tract infections in elite athletes.
• Nature Immunology. (2020). Host-microbiota crosstalk in immunity and inflammation.

GSSI Sports Science Exchange. (2022). Gut microbiome stability and athlete immune health.