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ChatGPT vs. Onetrack Club: Carb-Loading Myths

Updated: Jan 16

ChatGPT and Onetrack Club Sports Nutritionist Justin Reid-Simms go head-to-head to unravel the top ten carb-loading myths for runners.

A giant plate of chips being served for carb-loading runners in a restaurant

For all runners keen to improve their performance the same core problems keep cropping up. Is that a niggle? Am I properly rested? Am I fuelling correctly? Why am I not getting faster? In this article, we compare the advice on carb-loading offered by ChatGPT with the advice you can get from our Onetrack Club expert. Which one tells you what you really need to know about loading those carbs? Let’s find out…

In the ever-evolving world of fitness and nutrition, myths often find their way into the conversation, and one topic that has been shrouded in misconceptions is carb-loading for runners. As marathon season approaches and enthusiasts gear up for their next big race, it's essential to separate fact from fiction when it comes to fuelling strategies. Let's debunk the top ten myths about carb-loading, bringing clarity to a practice that has become both revered and misunderstood in the running community.

Myth: Carb-Loading is Essential for Every Runner

ChatGPT: Carb-loading is not a one-size-fits-all strategy. While it can benefit long-distance runners preparing for a marathon, it might not be necessary for those participating in shorter races. Individual needs vary based on factors such as training intensity, duration and personal metabolism.

JRS: ChatGPT is correct on this one! Whilst carb-loading strategies are important for longer endurance events, increasing your muscle glycogen stores isn’t always about eating more carbs. A reduction in training volume or intensity plays a part, what your normal diet looks like will determine how much you need to add, and if you’re aiming for shorter distances things will look very different.

Myth: The More Carbs, the Better

ChatGPT: Loading up on excessive carbs isn't the key to success. Quality matters over quantity. Focus on complex carbohydrates such as whole grains, fruits and vegetables as opposed to refined sugars. A balanced diet remains crucial for overall health and performance.

JRS: Just as protein isn’t going to build your muscles for you, carbohydrates aren’t a guarantee of running success. Periodizing your carbohydrate intake is important from a weekly perspective, focusing on fueling the hard sessions and going lighter on carbohydrate intake on the easy days. That can be expanded on in daily timings to give you the best outcome from training sessions.

Myth: Carb-Loading Starts the Night Before the Race

ChatGPT: True carb-loading is a gradual process that occurs over several days leading up to the race. Attempting to consume an excessive amount of carbs the night before may lead to discomfort and won't provide the sustained energy needed during the race.

JRS: Carb-loading needs a plan tailored to the individual athlete. We know that a lot can be done in the 36 hours before a race by increasing carbohydrate intake. But doing what is optimal according to the scientific literature and what is feasible for the individual means developing a strategy that takes the individual’s experience of training and racing into account. 

Myth: Carb-Loading Means Overeating

ChatGPT: Carb-loading is about optimizing glycogen stores, not overeating. It involves a slight increase in carbohydrate intake combined with a reduction in training intensity, allowing the body to store more glycogen without unnecessary weight gain.

JRS: It may feel like overeating for some athletes, when there is a focus on increasing carbohydrate intake. When we increase glycogen stores we also increase the amount of water our body stores, so it’s not uncommon to see some weight gain on the scales. Every body is different and, if you’ve been particularly low-carb during training, this weight gain will be more pronounced.

Myth: Carb-Loading Works for Everyone

ChatGPT: Some runners may not benefit significantly from carb-loading. Individuals with certain dietary restrictions, health conditions, or those who follow low-carb diets regularly may find alternative strategies more effective.

JRS: It depends on the distance, but ensuring that you have adequate muscle glycogen for the event you’re taking on is an important part of competition prep. For most long-distance runners, increasing muscle glycogen allows you to fuel your body for the duration of the event. Training strategies and fueling strategies can help our body to utilize other fuel sources and improve fat oxidation. But the intensity of racing is likely to mean that energy demands are met by glycogen and not fat. Interestingly, a recent study demonstrated that those on low-carb diets benefit from carb-loading and taking on carbs during a race.

Myth: Protein Should Be Avoided During Carb-Loading

ChatGPT: Protein is a crucial component of any runner's diet. While carb-loading emphasizes increased carbohydrate intake, maintaining an adequate protein intake is essential for muscle repair and recovery. Striking the right balance is key.

JRS: Protein is key for repair after workouts, maintenance of lean muscle mass and a healthy immune system. It’s best to take a sensible approach to protein intake and avoid restrictions during the tapering/carb-loading phase.

Myth: Carb-Loading Guarantees Success

ChatGPT: While carb-loading can enhance endurance, it's not a magic bullet for success. Proper training, hydration and overall race-day strategy are equally important. Relying solely on carb-loading without considering other factors may lead to disappointment.

JRS: Nothing guarantees success in running. The right kind of carb-loading for you in conjunction with good race-day nutrition could be the difference between a PB and just missing out. But without proper training, an appropriate level of fitness, and staying injury-free the marginal gains are worthless. 

Myth: Carb-Loading Is Only for Elite Athletes

ChatGPT: Carb-loading can benefit runners of all levels, not just elite athletes. Whether you're a seasoned marathoner or a first-time half-marathon participant, optimizing glycogen stores can improve endurance and performance.

JRS: Everybody can benefit from being properly fuelled before a race. How much that affects an individual on the day will depend on their regular diet, body weight, goals, training experience, etc. Learning how your body responds to carb-loading early on in your racing can help to inform and improve your strategies in the future.

Myth: High-Fat, Low-Carb Diets Are Incompatible with Carb Loading

ChatGPT: Runners following high-fat, low-carb diets can still benefit from carb-loading. Adapting the strategy to incorporate healthy carbs while maintaining the principles of their chosen diet can optimize performance without compromising dietary preferences.

JRS: Adapting a high-fat, low-carb diet may reduce metabolic flexibility (a person’s ability to use fats or glycogen as fuel effectively). However, because glycogen is the preferred fuel source for higher intensity (even marathon-paced) work, a person who typically eats high-fat, low-carb food will see a benefit from carb-loading and taking extra carbohydrates on race day.

Myth: Carb-Loading Negatively Affects Weight

ChatGPT: When done correctly, carb-loading should not lead to significant weight gain. The focus is on increasing carbohydrate intake while moderating overall calorie consumption. Any small weight increase is likely due to increased glycogen storage, not fat accumulation.

JRS: Runners will see an increase in weight and, although that extra weight consists of glycogen and the water stored along with it, individuals need to make a decision about how much carb-loading to do and how they feel while racing when a little heavier. There are techniques to mitigate this effect, such as choosing to eat a low-residue diet in the lead-up to an event to avoid excess weight being stored in the intestine. Some athletes choose to carb-load using carb drinks instead of rice or pasta in order to feel lighter on race day.

What’s the verdict?

As the running community continues to grow and evolve, it's essential to approach carb-loading with an informed perspective. By dispelling these myths, runners can make more educated decisions about their nutrition so as to optimize their performance on race day. Remember, the key to success lies not in adhering blindly to standardized advice on nutrition but in finding a personal approach attuned to your particular needs and goals as a runner.

So why waste time testing one-size, online solutions to those crucial nutritional problems, when our dietary experts at Onetrack Club can solve them in a way that’s designed to suit you? You can find out more about bespoke nutrition programming here.

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