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Carb Cycling – How It Works, Benefits and Side Effects

What Is Carb Cycling?

Carb cycling is a relatively new dietary approach to manage your diet for weight loss, muscle gain and even weight maintenance. The concept of carb cycling involves carb manipulation by alternating your carb intake periodically such as daily, weekly or monthly.

The specific requirements of carb cycling will depend on your lifestyle and goals you want to achieve. When carb cycling, you have to increase and decrease carbohydrate intake according to a dietary plan on different days of the week. It may involve high carb days, medium carb days and low carb days as well as no carbs days.

Carb cycling allows you to better utilize fat as fuel as opposed to burning carbs and muscle tissue for fuel. Also, when you eat high carb foods, they raise serotonin levels in your brain, sometimes called happy chemical, which makes you feel better.

How Does Carb Cycling Work?

In principle, carb cycling aims to match the body’s requirement for calories based on a variety of factors and dietary preferences. For example, people with intense training days require higher amounts of carbohydrates so they have to increase their carb intake on training days and cut back on days with low or no physical activity. Others use carb cycling based on the amount of body fat they carry. The leaner they get, the more they can increase the number of high carb days. On high carb days, the carbs you consume are primarily used to refill glycogen in the muscles and build muscle instead of being used for fat storage.

High carb days are intended for:

  • Refueling glycogen in the muscles
  • Improving athletic performance
  • Sparing protein by reducing muscle breakdown from training, dieting and carb limitations
  • Boosting functioning of appetite and hunger regulating hormones such as ghrelin and leptin to mitigate hunger signals

Low carb days are intended for:

  • Inducing a caloric deficit by burning fat more effectively relative to the amount of calories required for maintaining current body weight (energy homeostasis) and improving the body’s metabolic flexibility
  • Restraining calories on a weight loss diet
  • Managing and manipulating insulin spikes
  • Targeting carbs around workout days to improve the body’s insulin sensitivity which allows the cells of the body to use blood glucose more effectively and reduce blood sugar.

Carbs, Energy Production and Metabolic Response

How are carbs turned to energy?

Carbohydrates, often called carbs, are essential nutrients in supplying energy for our body to function. When our body digests carbs, they’re broken down into a type of sugar called glucose, which is then released into the bloodstream. When this happens, the pancreas is triggered to produce a hormone called insulin, which allows the glucose to enter the cells to help them convert it to energy. Our body uses glucose as its primary fuel source for energy.

Energy storage

When our body doesn’t need to use glucose for energy, it stores the leftover glucose in the cells of liver and skeletal muscles. This stored form of glucose is known as glycogen, which acts as our body’s backup fuel source. Our body can store enough glycogen to fuel us for about a day. Our body also converts any calories it doesn’t need to use straight away into triglyceride. While glycogen functions as a short term energy reserve, triglyceride functions as a long term energy reserve in adipose tissue (body fat). Glycogen only stores half as many calories as a gram of triglycerides.

If you aren’t doing enough physical activity and are still consuming a lot of carbs, your body ends up storing the excess carbs as fat. This results in becoming overweight or even obese. However, if you restrict your daily carb intake, your body cannot not store the extra glucose. Instead, it makes use of fats already stored in the cells to produce energy. As a result, your body can shed pounds in the form of fat, helping you lose weight.

Metabolic response to calorie intake

Your metabolism revs up or slows down based on your calorie intake. Consuming a certain amount of carbohydrates signals the body to produce some hormones such as leptin and thyroid. Leptin functions as a major regulator of the body weight and metabolism. When you gain weight, the production of leptin increases. This tells the body that fat storage is adequate and causes the body to burn fat rather than continue storing the excess. It also increases the production of thyroid stimulating hormone (TSH), which helps in using up excess calories.

If your metabolism is fast, you will end up expend more calories during rest and physical activity. This means that you will have to consume more calories to maintain your body weight. This is how some people can eat more than others without gaining weight.

You need to adjust your carb intake from day to day. For example, if you are going to the gym, you can consume more carbs. If you are going to be sitting for most of the day without doing any physical activity, you should try to restrict your carb intake.

Weight Loss and Muscle Gain

When balancing carb consumption, the amount of complex carbs you have to consume depends on your body composition goals. Usually, extremely low carb consumption is used for weight loss (less than 5%), while much higher carb consumption is required for muscle gain (about 55-60%). Also sports people should follow a higher carb diet than average people as they have higher energy needs. For non-athletes, it’s always better to adopt a more balanced diet.

Weight Loss with Carb Cycling

Carb cycling can help you with weight loss by maximizing how your body uses its energy. Also, it may be helpful for breaking through weight loss plateaus. As with any diet, the main premise behind weight loss is maintaining a calorie deficit. If you eat less than your body burns over a certain period of time, you are likely to lose weight.

By aligning high carb days with workout days and scaling calories back on low carb days, you will be able to burn more fat to lose weight. How you alternate between high and low carb days as well as the amount of carbs you consume on each type of day will vary depending on the type and amount of physical activity you are doing.

Keep in mind that every carb cycling plan is different. You’ll have to tailor your carb intake according to your personal needs. A standard plan will have a very low carb intake for two to three days and a high carb intake for one day. Low carb days, when done in succession for two to three days, prompt the body to use up its stored energy in muscles (glycogen) and start burning body fat (ketones) for fuel which will lead to weight loss.

Of course, your high carb days must not consist of all fries and pizza! Wholegrain foods are much healthier options than refined sugars for your calorie needs. If you consume high fiber carbs on your low carb days, you’ll feel full longer. As such, you can manage your weight loss diet more effectively as you won’t be tempted to binge.

Muscle Gain With Carb Cycling

Muscle Gain with Carb Cycling

Carb cycling can be a great way of gaining muscle and improving physical performance for athletes. Building muscle requires a lot of energy to power through exercise. In other words, you can’t build muscle without exercising. For muscle gain, you will need a caloric surplus and a high protein intake so your body is less likely to break down muscles for energy. Protein is very important for building muscle that helps preserve muscle tissue and provide recovery from workouts. As your body can’t store protein, any leftover protein is used for energy or stored as fat in the body.

By combining the anabolic power of insulin manipulation with carb cycling, you can build muscle and burn fat at the same time. Lowering your carb intake on certain days promotes better insulin sensitivity as it allows the cells to use glucose more effectively resulting in less body fat.

Complex carbs are vital for muscle building due to their protein sparing properties. Protein sparing is a process by which the body obtains energy from sources other than protein such as fats and carbs in the form of glycogen stored within the muscles instead of breaking down muscle tissue for energy. This process also promotes muscle growth. However, carbs are not needed to build muscle if the protein intake is adequate.

When carbs aren’t readily available and fat or protein is the primary source for energy, low carb utilization can lead to a higher rate of fat burning. The key to burning more fat is to align your low carb days (creating a caloric deficit) with higher protein intake.

Timing and adjustment of carb consumption

The timing of carb consumption also affects physical performance and muscle building. High carb days should be aligned with the days of intense training. You have to consume complex carbs when your body’s insulin sensitivity is the highest. You should consume carbs a few hours before workouts so you have plenty of glycogen to energize the body. After workout, it’s important to replenish glycogen stores for later use by consuming carbs. Consuming carbs after workout can help prevent muscle loss and repair muscle tissues to ensure faster muscle recovery.

Catabolic state – A warning about excessive training!

Be careful that if you are involved in excessive physical activity coupled with a lack of proper nutrition, particularly protein, your body can enter a catabolic state. This means that your body starts to use muscle tissue to obtain energy. If this situation continues for extended periods of time, it can eventually lead to major muscle loss and overall decrease in health with various unwanted side effects such as extreme fatigue, insomnia, joint and muscle pain.

Is Carb Cycling Right For You?

Carb cycling can be a counter-productive way of dieting for some people. Success at carb cycling involves meticulous tracking of macronutrients with a food journal or app. You must work out the amount of carbs you’ll need every day. This may not be as easy as it seems since the amount of carbs you should consume will have to be tailored to your specific needs. Furthermore, for some people, constantly measuring, tracking and counting carbs and calories can be difficult and lead can to an unhealthy attitude towards eating.

There are certain groups of people who are most likely to have the most success with carb cycling. These people include:

  • Competitive and recreational athletes who train three to four times a week (endurance training, weight training) and want to increase their muscle mass while boosting their athletic performance
  • People who want to lose weight or maintain weight

It’s important to note that if you keep your carb intake too low for several days, you can experience ill side effects such as sugar cravings, dizziness, fatigue, lethargy, brain fog, moodiness, irritability, bloating and nausea. This is known as “carb flu” which is a temporary condition. This happens during the adaptation stage when your body uses up all its available carbohydrates and is shifting to using fat as fuel.

It’s also important to differentiate between that the short term and long term effects of carb cycling on the body. While the body can manage carbohydrate and calorie restrictions in the short term rather well, however, such a nutritionally restrictive dietary approach based on low carbohydrates can put unnecessary stress on the body in the long run.

If you constantly crave foods you are not supposed to eat, or if you find that this type of diet is adversely affecting your attitude and mood, or if you feel unusually fatigued, then this is a sign that carb cycling is not for you. As with any restrictive and rigorous diet, you have to know when it is time to stop.

Who Should Avoid Carb Cycling?

Carb cycling is not suitable for everyone. It may pose serious health risks for people with certain medical conditions:

  • People with a history of eating disorders – Constantly being aware of carb and calorie intake can aggravate disordered eating patterns.
  • People with Hashimoto’s disease – Due to low carb intake, people suffering from Hashimoto’s disease (an autoimmune disorder where the immune system erroneously attacks the thyroid gland) can experience a drop in their thyroid hormone levels that can aggravate hypothyroidism. Hashimoto’s disease is the most common cause of hypothyroidism where the thyroid gland is prevented from releasing enough of the two main hormones it produces, T3 and T4. This condition can slow down the metabolic rate and cause weight gain.
  • People with adrenal fatigue – Low carbohydrate intake can put more pressure on adrenals that are already fatigued and lead to certain health problems such fatigue, loss of appetite, salt cravings, weight loss, muscle weakness, depression, low blood pressure (hypotension) and low blood sugar (hypoglycemia).
  • People with depression and anxiety – Changing eating patterns can adversely affect people suffering from depression and anxiety. This can lead to worsening mood swings and mental health problems.
  • Women who are pregnant or lactating – They should refrain from carb cycling as they need a constant supply of carbohydrates which provide energy to support the mother and growing baby during pregnancy.
  • People suffering metabolic syndrome – People with metabolic syndrome (a cluster of conditions occurring together which increases the risk of heart disease, heart stroke and type 2 diabetes) should avoid carb cycling as they require a steady supply of carbohydrates to stay healthy.
  • Diabetic people taking insulin – While carb cycling can be beneficial for regulating insulin levels, however, it can create complications for those people on insulin medication.

Final Words

Whether you want to lose weight, maintain the weight you recently lost or just gain muscle, carb cycling can be an ideal dietary regime to reach your goals. Lowering your carbohydrate intake on certain days of the week that corresponds to specific workouts can help you increase muscle mass, shed unwanted body fat and maintain a healthier body weight.

Carb cycling is an extremely rigorous diet so it should only be used for short-term to achieve your body weight and muscle gain goals as well as improve your health markers. Carb cycling can also pose health risks for some people with certain medical conditions. If you find that carb cycling is negatively affecting your life, you should stop and follow a different diet. So be sure to check with your doctor before embarking on any restrictive dietary lifestyle change.

“The Ultimate Guide To Carb Cycling For Fat Loss and Muscle Gain”

  1. Carb Cycling – How It Works, Benefits and Side Effects
  2. How To Start A Carb Cycling Diet
  3. Carb Cycling Diet Plan For Fat Loss and Muscle Gain
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