Running: Should You Spit or Swallow, and Why?

Should You Spit or Swallow While Running?

While individual preference and perceived comfort play a role, from a physiological and public health standpoint, swallowing saliva during running is generally the more advisable practice, aiding minor fluid and electrolyte retention while promoting hygiene.

The Runner's Saliva: More Than Just Spit

Saliva, often overlooked, is a complex fluid critical for oral health and initial digestion. It consists of water, electrolytes, enzymes (like amylase for carbohydrate digestion), mucus, and antimicrobial compounds. Its primary roles include lubricating the mouth, initiating food breakdown, protecting teeth, and facilitating speech. During exercise, the body's physiological responses can alter saliva production and perception. The sympathetic nervous system, activated during physical exertion, typically reduces saliva flow, leading to a sensation of dry mouth. Conversely, mouth breathing, common during moderate to high-intensity running, can rapidly evaporate moisture, further contributing to this dryness. Sometimes, what feels like "excessive" saliva is actually thicker, more viscous saliva that is harder to swallow, or simply the result of increased mucus production in the airways due to exercise or environmental factors.

The Physiological Arguments for Swallowing

From a scientific perspective, retaining and swallowing saliva offers several minor yet cumulatively beneficial physiological advantages for the runner:

• Fluid and Electrolyte Conservation: While the volume of saliva is small, swallowing it contributes to the body's overall fluid balance. During prolonged exercise, even minor fluid losses can add up. Saliva also contains small amounts of electrolytes (e.g., sodium, potassium), which are essential for nerve and muscle function. Retaining these, however small, supports the body's homeostatic mechanisms.
• Digestive Function: If you are consuming energy gels, sports drinks, or other carbohydrates during your run, the enzymes in saliva (like salivary amylase) begin the breakdown process. Swallowing ensures these enzymes are delivered to the digestive tract, aiding in the efficient processing of fuel.
• Oral Health: Swallowing saliva helps maintain a moist oral environment, which is crucial for neutralizing acids produced by bacteria, washing away food particles, and reducing the risk of dental issues, especially important during prolonged periods of mouth breathing.
• Natural Bodily Process: Swallowing is a natural and continuous bodily function. Disrupting this through spitting is largely a behavioral choice rather than a physiological necessity.

The Arguments and Realities of Spitting

The act of spitting during a run is largely driven by perceived comfort and psychological factors, rather than a clear physiological benefit:

• Perceived Comfort and Airway Clearance: Many runners report a feeling of relief or better airflow after spitting, particularly when saliva feels thick, frothy, or excessive. This can be psychological or a temporary clearing of mucus from the throat and airways, which can accumulate due to increased breathing rates and environmental irritants.
• Managing "Thick" Saliva: When the body becomes dehydrated, saliva can become more viscous and less watery, making it feel difficult or unpleasant to swallow. In such instances, spitting might feel like the easier option. However, this often signals inadequate hydration rather than a need to expel fluid.
• The "Spit and Run" Culture: Spitting is a common sight in competitive running and other sports. This can be due to the intense physical exertion, heightened focus, and a general acceptance within the athletic community, often without considering the broader implications.

Public Health and Etiquette Considerations

Beyond individual physiology, the act of spitting in public carries significant public health and social implications:

• Germ Transmission: Saliva contains bacteria, viruses, and other microorganisms. Spitting disperses these into the environment, increasing the risk of transmitting infections, especially in crowded areas or shared public spaces. This concern is heightened during periods of respiratory illness.
• Environmental Impact: Spitting is unsightly and can contaminate public areas, trails, and sidewalks, creating an unpleasant environment for others.
• Social Responsibility: In communal spaces, considerate behavior is expected. Spitting is widely considered poor etiquette and disrespectful to fellow runners, pedestrians, and the general public.

Practical Recommendations for Runners

For optimal health, performance, and social responsibility, consider the following:

• Prioritize Hydration: The most effective way to manage the sensation of "thick" or "excessive" saliva is to maintain proper hydration before, during, and after your run. Adequate fluid intake ensures saliva remains watery and easy to swallow.
• Individual Comfort vs. Physiological Benefit: While the physiological benefits of swallowing are minor, they are consistently positive. Weigh your personal comfort against the minor physiological advantages and the significant public health/etiquette concerns of spitting.
• Consider Your Environment: If you are running in isolated natural environments, the public health impact of spitting might be lower. However, in urban areas, parks, or crowded trails, the impact is much greater.
• Adjust Intensity if Needed: If you consistently find yourself struggling with saliva at high intensities, assess your breathing technique and hydration. Sometimes, a slight adjustment in pace can alleviate discomfort.
• Oral Hygiene: Good oral hygiene can reduce the bacterial load in your mouth, making any accidental swallowing or even the act of spitting less impactful, though still not recommended.

When to Seek Professional Advice

While spitting or swallowing during a run is generally a benign choice, persistent or extreme issues with saliva production might warrant a consultation:

• Persistent Dry Mouth (Xerostomia): If you experience chronic dry mouth unrelated to exercise or hydration, it could indicate underlying medical conditions, medication side effects, or salivary gland issues.
• Excessive Salivation (Sialorrhea): If you consistently produce an unusual and excessive amount of saliva that interferes with breathing or comfort, it could be a sign of neurological conditions or other health concerns.
• Digestive Discomfort: If swallowing saliva or ingesting nutrition during runs consistently causes significant gastrointestinal distress, consult a sports dietitian or physician.

Conclusion

The question of whether to spit or swallow while running boils down to a balance of minor physiological benefits, personal comfort, and significant public health and social responsibility. From an exercise science and kinesiology perspective, swallowing saliva is the physiologically sounder and more socially responsible choice. It contributes, however minimally, to hydration and electrolyte balance, aids digestion, and preserves public hygiene. Prioritizing proper hydration is the best strategy to manage saliva consistency and reduce the urge to spit, allowing runners to focus on their performance and contribute positively to shared spaces.