Carbohydrates (aka carbs) have a gotten a bad rap. Just ask anyone what they need to do to lose weight, and they will likely say: “Cut back the carbs.” As a nutrition coach, this is one of the most common misconceptions that I come across.
Yes, reducing overall calories by cutting carbs will work for losing weight in the short term; however, it is not sustainable and could negatively affect your performance and overall health.
In this article, we will cover:
• What carbs are and how the body uses them,
• Why athletes need carbs to perform,
• The dangers of NOT eating carbs,
• How many carbs should be consumed (and when) to boost performance and recovery?
What Are Carbs?
Think of carbs as fuel, the body’s preferred energy source that powers your body through intense exercise as well as day-to-day activities. You can find carbs in bread, fruits, pasta, rice, vegetables, and many other food sources. Eating carbs will give muscles energy, fuels the brain and nervous system, and ensures that the protein within the muscles is not broken down into fat.
Here is the science-y stuff. The carbs we eat are broken down and converted into glucose by the liver to be used by the brain and muscles. Any glucose that is not needed immediately for energy is converted into glycogen and stored for use later in the muscles and the liver.
Intense exercise depletes these glycogen stores, which is why it is important to optimize glycogen levels and replace them post-workout.
How Are Carbs Stored?
Glycogen is made and stored in the liver and muscles. The muscles hold the most glycogen, which is not surprising when you consider that muscles account for between 20-30 percent of your total mass. They can typically store between 350-450 grams of glycogen, enough energy for around 90 minutes of endurance exercise. The glycogen stored in the muscles cannot be used elsewhere in the body.
The liver, in contrast, stores around 100 grams of concentrated glycogen and uses it around the body. The glycogen stored in the liver is responsible for maintaining blood sugar and energy levels throughout the day. The liver also feeds the brain the glycogen it needs to keep going — another reason not to eliminate carbs from a diet.
What Are The Risks of NOT Eating Carbs?
Cutting carbs is a popular weight-loss strategy (think Atkins and other low-carb diets), and that is because it can work at least in the short term. However, in the long run, low-carb diets can impede the body’s ability to function at its best – especially for athletes.
People with sedentary lifestyles need less fuel and may be able to get away with fewer carbs. Athletes who train regularly with intensity and adopt a low-carb diet, however, can cause a significant reduction in thyroid output, testosterone levels, hormones, cognitive function and more.
Reduced Thyroid Output
T3, the most active thyroid hormone, is responsible for the management of blood glucose and correct metabolic function. Studies show that T3 is sensitive to carbs and will drop if calorie and carb intake becomes too low, causing a cold and sluggish feeling.
Impaired Cognitive Function
Muscles are not the only organs to be heavily impacted by carbs; the brain is too. The brain is the greediest organ in the body, continually sucking up energy from the bloodstream but failing to store any itself. The brain sends and receives electrical impulses 24 hours a day from more than 80 billion neurons. The brain is busy even when we are asleep, helping us to process memories and make sense of the day. No wonder it needs energy.
The brain’s primary fuel source is glucose, derived from carbs. For an organ that only takes up about 2% of our body weight, it consumes up to HALF of our body’s glucose. Do not shortchange the brain.
MEN – Falling Testosterone and an Increase in the “Stress Hormone” Cortisol
Male athletes who exercise regularly need to maintain their supply of carbs or risk their testosterone levels falling, while cortisol levels rise. Testosterone increases protein synthesis, the act of building muscle. Cortisol, however, released during moments of high physical or mental stress (think of the body’s fight-or-flight instinct), works the opposite way. It seeks to reduce protein synthesis and halts tissue growth, all of which is a fancy way of saying that it prevents muscle building.
Even those trying to lose weight will want to maintain lean muscle mass. Doing so encourages the body to burn fat stores rather than muscle, aiding in weight loss. Exercising without eating enough carbs leaves many people feeling sluggish and cranky, and at risk of not losing much weight in the long term.
WOMEN – Disruption to Hormone Production
Active women who fail to eat enough carbs may face disrupted hormone production. These hormonal disruptions can result in menstrual cycle irregularities (or lack thereof); reduced fertility; blood sugar swings; loss of bone density; fatigue and lack of sleep, and a host of other chronic health problems. Psychologically, women can suffer from depression and anxiety. The irony of cutting carbs while exercising is that women can end up with more body fat, rather than less.
Do Carbs Make Me Fat?
Many have speculated that high-glycemic carbs spike insulin and encourage fat storage, but research shows that carbohydrate-laden meals are primarily stored as glycogen and not fat. Carbs alone won’t make a person fat, but one may put on weight if they are consuming more calories than they are burning off.
Carbs are not inherently bad; in fact, carbs are crucial for many people, particularly athletes who do weight or high-intensity training.
How Do Carbs Help My Performance?
When weightlifting or doing high-intensity exercises such as CrossFit, the body uses glycogen stores to fuel workouts. Studies theorize that bodybuilders can deplete the glycogen in their muscles by as much as a third or more during resistance training. It is important to replenish those stores to maximize performance and aid recovery. Low glycogen stores cause muscle fatigue, muscle weakness and an inability to complete the high-intensity exercise.
Studies have proven that glycogen stores can drop significantly after just one hour of exercise. Experts recommend intra-workout carbs if training at high intensity for 90 minutes or more to aid endurance and performance.
How Many Carbs Should I Eat Per Day and When?
There is no one-size-fits-all approach when it comes to recommending carb intake. The ideal amount of carbs to eat per day will depend on personal factors such as:
1. Current body fat and lean muscle mass,
2. Daily activity levels and training regimen,
3. Goals – fat loss or muscle gain and increased strength, or better endurance?
The answers to each question will dictate how many carbs an individual should consume daily.
What about Carbohydrate Timing?
For most individuals, carbohydrate (or nutrient) timing does not play a significant role in their nutritional protocol. We believe that an initial focus on total caloric intake, food quality, sleep, hydration, and exercise is far more critical.
Here are a few general rules for nutrient timing:
1. Do not eat right before a workout. Instead, eat carbs and protein with very little fat 90 minutes before working out. We don’t want the body to be digesting food while trying to fuel a workout.
2. Consume carbs and protein post-workout to help the body shift to a parasympathetic mode (aka recovery mode).
Are you ready to add carbs back into your life and eat a balanced diet? Our experienced nutrition coaches have a passion for educating our clients on proper nutrition. Click here to view our coaching programs and get started! 🙂