Understanding Vasovagal Syndrome in Athletes

Vasovagal syncope, sometimes called vasovagal syndrome, is surprisingly common. Up to one-third of people experience at least one episode in their lifetime, and by age 60, that number rises to around 40%. For runners and student athletes, it can be especially frustrating and discouraging.

This condition occurs when the body overreacts to certain triggers such as standing for long periods, heat, stress, pain, dehydration, or intense exercise. These triggers can cause a sudden drop in heart rate and blood pressure, temporarily reducing blood flow to the brain. Episodes may strike unexpectedly during cross country races, games, training or competition, making it difficult to perform at full capacity and often leaving athletes feeling anxious or hesitant to push themselves.

Common symptoms include:

Dizziness or lightheadedness
Nausea
Tunnel or blurred vision
Pale skin and sweating
Fainting or feeling like you might faint

For athletes — especially runners vasovagal episodes are often triggered by:

Dehydration or low blood volume (not enough fluids or electrolytes)
Standing suddenly after exertion
Overheating
Rapid changes in blood pressure post-exercise
Insufficient fueling (low blood sugar)

Many sports medicine professionals recommend increasing both fluid and sodium intake to help the body retain water and maintain stable blood volume.

However, if nausea or vomiting has worsened, that may indicate an imbalance in timing, electrolyte concentration, or gut sensitivity — issues that can often be corrected with personalized nutrition strategies.

Six nutritional strategies we recommend to manage and improve vasovagal syndrome

1. Key Goal: Maintain Blood Volume and Prevent Sudden Drops in Blood Pressure

Vasovagal episodes are often triggered when blood pressure drops and blood flow to the brain decreases, which can happen with dehydration or inadequate sodium.

Hydration and electrolyte balance are critical.

Daily Hydration Targets

Aim for ½ to 1 ounce of fluid per pound of body weight per day.
- Example: A 120-lb athlete = 60–120 oz fluids/day.
More is needed in hot or humid weather and on double workout days. See our hydration tip sheet HERE.

Sodium & Electrolyte Targets

2,500–4,000 mg sodium per day for active athletes (sometimes higher under medical supervision).
Use electrolyte drinks like Momentous FUEL *Code WENDIIRLBECK to save 15%, LMNT, Liquid I.V., Skratch Labs, or Gatorlytes—especially before and during runs.
Salt meals liberally (soups, pretzels, pickles, salted rice, or electrolyte tablets can help).

2. Pre-Run Fueling & Hydration (2–3 hours before)

The pre-run meal should help maintain blood glucose, hydration, and stomach comfort.

Sample pre-run meal (2–3 hrs before):

1–2 cups water or electrolyte drink
1 cup white rice or 1 bagel
1–2 egg whites or PB2 powder
1 banana or small piece of fruit
Optional: 300–500 mg sodium via salt or electrolytes

Avoid: heavy fat, fiber, or dairy right before a run (they slow digestion and can worsen nausea).

3. 30–60 Minutes Before Run

8–12 oz fluid with 400–600 mg sodium
Simple carbs like:
- Applesauce pouch
- Banana + small handful pretzels
- Cherry juice or coconut H20

This stabilizes blood sugar and prevents gut shutdown.

4. During Runs (Long XC Efforts)

For races over 30–40 minutes:
- Fluids: 3–6 oz every 15–20 min if tolerated
- Sodium: 300–600 mg/hour
- Carbs: 30–60 g/hour of activity (honey, applesauce, sports drink). Carbs are your energy not the enemy!
Gut training is key — practice fueling during workouts so her GI system adapts to digesting carbs and sodium while running.

5. Post-Run Recovery (Within 30–60 min)

Focus on rehydration, replacing sodium, and stabilizing blood sugar.

Sample recovery snack:

16–24 oz electrolyte fluid + 500–700 mg sodium
Smoothie with milk or protein powder + banana + oats
Or turkey sandwich with pretzels and fruit

6. Additional Considerations

Check iron and ferritin levels—low iron can worsen fatigue and dizziness.
Rule out low blood sugar (hypoglycemia) with a Nutrition with Wendi Sports Dietitian if feeling shaky, nauseous, or faint.
Gut training can reduce nausea over time — small, frequent intakes during training help the GI tract adapt.

The good news? Nutrition strategies can make a significant difference. Our team would love to review your athlete’s current fueling and hydration routine to identify what may be triggering unwanted symptoms — and to help optimize intake for steady energy, gut comfort, and recovery.

Apply for 1:1 Nutrition Coaching or schedule a Performance Fueling Consultation today to help your athlete feel and perform their best!

-In faith, health, and wellness
Wendi A. Irlbeck, MS, RDN, LD, CISSN

Follow us on Twitter, Facebook, and Instagram for more nutrition information. Services booking here to consult with Wendi for a team talk or QA session.

The Nutrition with Wendi team utilizes evidence-based science to tailor nutrition programs for athletes to optimize performance, minimize health risks, and enhance recovery from training while focusing on injury prevention. We partner with parents, athletes, health professionals, and individuals and offer elite nutrition and health guidance for optimal athletic performance, injury, and disease reduction. We provide virtual sports nutrition coaching, education, and presentations virtually in Texas, Florida, California, Minnesota, Ohio, Illinois, Indiana, Iowa, Nebraska, New Jersey, New York, North Dakota, Arizona, and Michigan. Our primary office is based in Nashville, Tennessee where we serve the greater Brentwood, Franklin, and Green Hills communities. Follow us on Twitter, Facebook, and Instagram for more nutrition information. Services booking here to consult with Wendi for a team talk or QA session.

Salari N, Karimi Z, Hemmati M, Mohammadi A, Shohaimi S, Mohammadi M. Global prevalence of vasovagal syncope: A systematic review and meta-analysis. Glob Epidemiol. 2024 Jan 6;7:100136. doi: 10.1016/j.gloepi.2024.100136. PMID: 38283939; PMCID: PMC10821537.