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Race Fueling

Nutrition Case Study: The Swollen Ironman

Marni Sumbal shares how she helped one triathlete learn from a fueling mistake that nearly cost her her life.

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Nutritionist and triathlon coach Marni Sumbal shares how she helped one triathlete learn from a fueling mistake that nearly cost her her life to becoming a successful Ironman finisher.

The Athlete

Heather Bellian Maumee, Ohio
48 years old
5’7’’, 136 pounds
Years in the sport: 5.5
Occupation: Physical Therapist
Triathlon coach: Caitlin Glenn of Crew Racing

The Incident

Heather arrived to Ironman 70.3 Raleigh fit, confident, and prepared for her fifth half Ironman on June 4, 2017. She finished the race in 6:37.51.

During the run, Heather experienced calf and abdominal cramping along with swollen hands but didn’t think too much of it. Soon after crossing the finish line, she vomited and immediately entered the medical tent for examination where she received two bags of IV fluids. Her condition worsened, so she went to urgent care where her sodium level was 121 mEq/L (a normal sodium level is between 135-145 mEq/L) and weighed in at six pounds more than her pre-race weight. Heather was rushed to the hospital. Her health was rapidly declining, as she experienced numbness in her hands and feet, tachycardia, confusion, and difficulty hearing. She was manifesting cerebral edema, with a seizure that followed. Almost 72 hours post-race, she was released to fly home after her life-threatening health scare, questioning her desire to continue in the sport. The diagnosis: severe hyponatremia.

My notes

Possible causes:
– High sweat rate/salty sweater, especially in the heat
– Not well-acclimatized to race in a warm environment (on race day, Raleigh hit 90 degrees with 100 percent humidity)
– Use of non-steroidal anti-inflammatory drug (Ibuprofen) pre-race
– Concentrated carbohydrate fueling plan (a mix of gels and sport drink)
– Straw-based hydration system on the bike (sucking through a straw forces inhaled air into the belly, increasing the risk for gas, belching, and abdominal cramping)
– Water and carbohydrate overload relative to sodium intake during the run
– IV fluid-induced hyponatremia

It was apparent that Heather’s plasma sodium levels dropped gradually throughout the race (hyponatremia) but reached a severely low level after the IV infusion.

After agreeing that Heather’s training or race strategy was not at fault, we made the following changes:

1. Sodium loading to expand plasma volume
Although preloading is not advised for everyone (ex. hypertensive individuals), it was critical for Heather to start the race with adequate blood levels of sodium. By consuming a beverage containing around 1200 mg of sodium for four consecutive days, we increased the likelihood for her to maintain blood volume to reduce cardio and thermal strain.

2. Nutrient timing
Gut training allowed Heather to maximize fitness while optimizing health. Consuming at least 350-450 calories (~60-80g carbs + ~10-15g protein and fat) in the 90 minutes before a long workout, along with regular consumption of sport nutrition during workouts (~120-250 calories per hour with 16-28 ounces of fluid), Heather was able to reduce feelings of fullness and bloating during exercise and increase gastric emptying and carbohydrate absorption, all while reducing GI symptoms.

3. Taking the diet as seriously as training – food is fuel.
A new easy-to-execute bike fueling plan, prioritizing a bottle/hr of liquid calories from a custom sport drink (4-5 gulps every 10 minutes) to avoid concentrated carbohydrate solutions. I created a custom blend from INFINIT nutrition (240 cal- ories, 60g carbohydrates, ~800mg of sodium in 24 ounce water per serving) to optimize gastric emptying and to meet carbohydrate, electrolyte, and fluid needs. She ate a few Clif Bloks to prevent tastebud fatigue from the liquid-calorie fueling plan.

4. Utilizing a hydration belt to drink to a schedule and to minimize overdrinking.
Each 10-ounce flask contained EFS electrolyte drink with ~96 calories and 300mg of sodium. Heather sipped each flask every 5-10 minutes and refilled the flasks with EFS each hour. She ate Clif Bloks as needed for a brain boost (ex. sucking on the block instead of quickly chewing it).

Test #1: Ironman 70.3 Steelhead

Result: 5:36, 11th AG, PR in all three disciplines, and no nutrition or health issues.

The final test: Ironman Kentucky

Heather arrived at IMKY equipped with a smart, well-practiced fueling/hydration plan, trust in her body, and solid training. With the support of her husband and coach out on the course, Heather completed her first Ironman in 12:25. With great energy all day long, she had no performance-lim- iting nutrition-related issues during the race.

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