9/14/2015
BY JILL CASTLE, MS, RDN of usaswimming.org
Just watch a swimmer cruise through a meal and load his plate with potatoes, pasta, rice, bread, rolls, corn, and desserts. It’s easy to see a hearty appetite. And it’s easy to see a love of food, especially carbs.
Why do swimmers crave food, particularly carbs?
Craving carbohydrate-based foods, both sugary desserts and starches, is a complex matter that may involve the neurotransmitters of the brain, nutrient use during exercise, food preferences, food availability, stress, emotions, sleep and more.
In other words, the explanation is not simple. Let’s look at a few theories:
The Brain
Areas of the brain, particularly the hippocampus, insula, and caudate, seem to be activated during episodes of food cravings. When craved foods are consumed, such as chocolate, an opiate sensor in the brain, which senses pleasure, lights up, triggering an addictive effect. There is evidence that food cravings and addiction affect the brain in a similar fashion.
Memory areas of the brain remember food cravings, as well as the reward or feelings associated with eating a craved food. Researchers suggest the memory center may be more powerful for food cravings than the reward center of the brain.
Restriction, or trying hard not to succumb to cravings, may yield an eventual indulgence. If the craving can be satisfied with a small portion, such as a few Hershey kisses or one cookie, that is fine. But, if a small amount of chocolate triggers an out of control binge, it might be better to have small, portion-controlled indulgences that take more effort to procure, such as a small scoop of ice cream from the local parlor.
The Diet
Some researchers have found that a lack of variety in the diet may lead to food cravings. And let’s not forget that carbs, especially sweets, taste good, reinforcing flavor preferences and potentially calling up pleasant memories of food.
Inadequate eating, either not enough calories or certain nutrients such as carbohydrate, is a common reason for carbohydrate cravings. If swimmers don’t fuel before their workouts, and recover with food afterward, they are more susceptible to food cravings later in the day. Even a missed snack can set the swimmer up for cravings, and result in choosing unhealthy foods, or overeating.
When the body doesn’t receive enough carbs (or has used up the stores of carbohydrate called glycogen due to intensive exercise), blood sugar levels may decrease, triggering the body to secrete gherlin, a hormone that increases appetite.
Stress and Emotions
Stress may be another trigger for craving food, especially carbohydrates. Ironically, when grabbing food to fulfill a craving, people often grab a source of carbs and fat. Carbs and fat both seem to boost the release of serotonin, which is a calming hormone. Eating chocolate or donuts when stress is high is an example of how a food craving can change the brain chemistry, inducing calm and/or relieving stress.
Emotions may also trigger a craving or desire to eat. Feelings of disappointment, sadness, or even celebratory feelings can lead the swimmer to seek food as a measure of comfort.
To stay on an even keel with eating, and cut down on cravings, follow these smart solutions:
Remember the pre-exercise snack. A piece of fruit or a medium-sized muffin can make a difference. Aim for about 1/2 gram of carbohydrate per pound for the young swimmer two to three hours before exercise. Examples include: 1 cup of dry cereal; a large banana; a chewy granola bar; a handful of pretzels.
Recover with a post-exercise snack. Replete the glycogen stores in the muscle and liver while offering the muscles a source of protein with a snack containing a blend of carbs and protein. Examples: a cup of flavored milk; a cup of Greek yogurt; cheese and crackers.
Don’t forget healthy fats. Olive oil, avocado, olives, and nuts may help keep appetite sated and ward off carbohydrate cravings.
Pick smart carbs. High fiber, whole grain carbs such as brown rice, whole wheat pasta and whole grain cereals digest more slowly, and leave the swimmer feeling fuller longer.
Watch out for too much sugar. When you eat a food you crave, such as a dessert, it kicks off the feel-good brain neurotransmitter called dopamine. Dopamine signals happiness. An association of feeling good after eating chocolate may reinforce the desire for more.
Jill Castle, MS, RDN is a registered dietitian, childhood nutritionist, and youth sports nutrition expert. She is the author of Eat Like a Champion: Performance Nutrition for Your Young Athlete. Learn more about Jill atwww.JillCastle.com.
