How can runners reduce respiratory tract infections?

Upper respiratory tract infections (URTIs) can be a major setback for runners who rely on their respiratory system. From the common cold to influenza and COVID-19, these infections can hinder performance. Nutrition plays a key role in reducing the risk of URTI. Read on to discover why URTIs are common among athletes, the risk factors involved, and effective strategies to lower your risk. Get ready to run strong through the cooler months with a robust immune system!

What is an upper respiratory tract infection?

An URTI is an infection of the nose, throat, and airways caused by viruses or bacteria, including the common cold (rhinovirus), sinusitis, influenza, and coronavirus. Symptoms include a stuffy or runny nose, sore throat, cough, sneezing, mild fever, headache, and fatigue. Typically, URTIs resolve within 7-10 days, but they can persist or worsen if they spread to the lower respiratory tract, potentially causing conditions like bronchitis or pneumonia.

What is the prevalence of URTI in runners?

Recreational runners often experience the common cold, also known as URTI, which is the most prevalent short-term illness among elite athletes. The higher susceptibility of athletes to URTIs is attributed to the intensity of their exercise routines. Intense training, particularly in endurance sports, can compromise immunity, making athletes more susceptible to infections or reactivation or viruses. Interestingly, elite athletes have a lower risk of experiencing prolonged URTI symptoms compared to those who do less training. This may be related to their overall healthier lifestyle, including factors such as personal, academic, or professional schedules, better recovery practices, improved sleep quality, and proper nutrition.

What is the impact of URTI on performance?

URTIs can temporarily hinder athletic performance by affecting lung function. However, URTIs typically do not impact cardiorespiratory endurance, which is the ability to sustain intense exercise. Conversely, in the long-term, URTIs can have a more substantial influence on performance. They can limit your training capacity, including reducing the distance and intensity of workouts. When you are unable to maintain your usual training volume or intensity due to URTIs, it can negatively affect your overall performance.

What are the risk factors for URTI in athletes?

1. Intense training: Overtraining without sufficient recovery weakens the immune system, increasing susceptibility to URTIs.
2. Inadequate recovery: Insufficient rest between training sessions impairs the body's immune response, raising the risk of URTIs. A proper taper before important events is crucial.
3. Exposure to cold and dry environments: Cold and dry conditions irritate the respiratory system, making it more vulnerable to infections. URTI rates peak in Winter but are common in Autumn and Spring too.
4. International travel: Athletes have a fivefold higher risk of illness after flying due to factors like dry air, close proximity to sick individuals, and exposure to recirculated air. Other factors include disrupted sleep, dietary changes, different environmental conditions, and increased population density at competition venues.
5. High stress levels: Psychological stress from training, competition, or personal life compromises immune function, making you more susceptible to URTIs.
6. Compromised immune function: Poor nutrition, lack of sleep, chronic illness, and underlying health conditions weaken your immune system, increasing the likelihood of URTIs.

What nutrition strategies can reduce the risk of URTI?

Eat enough calories: Low energy availability occurs when you do not consume enough calories to support training, daily activities and basic body functions. This can weaken immunity and increase risk of illness. Amenorrhea (absence of periods for three months or more) often indicates low energy availability in female athletes. Amenorrhea in elite female runners is linked to more URTI symptoms and lower immunity compared to runner with regular menstrual cycles (eumenorrhea). When managing a high training load, prioritise nutritional needs and minimise fasted training, which can stress the body and potentially impair immunity.

Mind your recovery: Minimising inflammation after exercise is important for maintaining a healthy immune system. Incorporating carbohydrates during and after exercise can help reduce stress hormones and support the immune system, potentially lowering the risk of URTIs. Protein plays a crucial role in building immune cells and promoting their proper functioning. In addition, consuming healthy fats and antioxidants, which can be found in a variety of sources such as fruits, vegetables, whole grains, nuts, seeds, and olive oil, helps to reduce inflammation.

Include enough vitamins and minerals: Vitamins and minerals are crucial for a strong immune system and URTI prevention. Carrots and leafy greens provide Vitamin A, citrus fruits and peppers offer Vitamin C, and nuts and oils contain Vitamin E, all supporting immune function. Boost your immunity with zinc from oysters and legumes, and selenium from Brazil nuts and fish. Iron from lean meats and beans also aids immune response. A balanced diet including fruits, vegetables, breads, cereals, dairy, meat, and alternatives provides sufficient immune-boosting nutrients. Multivitamin supplementation has not been found to reduce risk of URTI.

Check your vitamin D: Vitamin D is crucial for our immune system. In colder weather, our immune-supporting hormones and vitamin D levels drop, making us more prone to severe URTIs. If your vitamin D level is below 50ng/ml, a supplement is recommended. In places with weak sunlight, like lower latitudes or during winter, consider a daily small dose of vitamin D. Get sunlight on exposed arms and legs during midday to boost vitamin D. The needed sun exposure time varies by location. You can also get vitamin D from foods like margarine, oily fish, UV-exposed mushrooms, and eggs.

Look after your gut: Probiotics improve gut health and may reduce URTI effects. Eat probiotic-rich foods like yoghurt, kimchi, sauerkraut, miso, kefir, and more. Diversify your diet with whole grains, vegetables, nuts, and legumes to boost beneficial bacteria in your gut. If you're getting enough fibre, consider probiotic supplements during intense training, competition, or travel to lower URTI risk.

Summary

Runners face an increased risk of URTIs due to various factors associated with their training and lifestyle. By understanding URTIs, recognising risk factors, and implementing evidence-based nutritional strategies, you can safeguard your respiratory health, stay on track with your training goals, and achieve peak performance on race day!

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