Use Carb Cycling to Lose Weight and Boost Performance

Adjusting your carbohydrates based on your activity level may help you to bust through plateaus.

Expert Verified By: Aastha Kalra, MD

Weight loss and strength plateaus will happen at some point during your fitness journey, no matter how diligently you work on your goals. Some people might tell you to eat fewer carbs to achieve one goal and eat more to attain the other. But what if we told you that doing both — otherwise known as carb cycling — is actually the answer? 

Carb cycling — which, sadly, doesn’t involve eating bread on a bicycle — is a more advanced fat loss and strength-building technique not meant for beginners or those struggling with obesity. Rather, it’s a tactic recommended for relatively lean people who have hit a fat loss or strength plateau.

While it might sound complicated at first, a little know-how on how to track your calories and macronutrients is all you need to see if this technique is right for you. Below is a research-based article that covers everything you’d want to know about carb cycling. 

A spread of carbs
Tatjana Baibakova/Shutterstock

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What Is Carb Cycling?

Carb cycling is the practice of alternating high-carb and low-carb intake days. So one day, you might eat bowls of pasta, and the next, you’re basically going keto. Typically you’d eat more carbs on heavier training days and then cut carbs on less active days or even rest days. 

Here’s another way to think about it: Carbs are our body’s preferred energy source in the same way most cars use gasoline. So let’s say you’re heading on a cross-country road trip, but you know there’s going to be days you might stay put in a city and not drive so much. 

Your high-carb days would be the days you fill-up at the gas station, and you’d cycle them with pit stops when you’re not driving so much. After all, you wouldn’t really fill up the tank if you didn’t plan on driving it a lot, would you?

Energy, though, isn’t the only reason one might carb cycle. People also do it to change their physique based on aesthetic goals, as muscles tend to look “fuller” after consuming many carbs.

Oftentimes, overall calorie intake is also higher on high carb days, though some manipulate their carb intake within the same number of calories. The protein intake remains the same across all days, while fat intake usually increases when the carbs decrease and vice versa.

Dr. Aastha Kalra, a New York-based physician who focuses on weight loss, says people may alternate their carb intake from week to week or month to month. And unlike many fat loss tips found on the internet, she says carb cycling has some proof to back it up. 

“It is based on the science that when you lose weight or lower your daily caloric intake, your basal metabolic rate decreases,” she says. “Therefore, on days when the caloric intake is higher, and the carbohydrate proportion is higher, it helps to maintain the basal metabolic rate and decrease hunger.”

How Cycling Carbs Affects Your Health and Performance 

You might be wondering, “Isn’t overall calorie intake the most important factor for weight loss? Why do I have to switch up carbs?” And you’d be excused for thinking that, but there are multiple reasons why carbs are the main player here. 

Research has shown that timing carbohydrates around workouts may help optimize both physical performance — aka how well you do in the gym — and recovery afterward. (1)(2)

“Based upon the fact that fatigue during intense, prolonged exercise is commonly due to depletion of muscle and liver glycogen, which limits both training and competitive performance, a higher carbohydrate intake at times before, during, and after exercise may help,” says Dr. Kalra. “The goal is to have as many carbohydrates in the body as possible during the latter stages of prolonged intense exercise when the ability for intense exercise usually becomes limiting to performance.”

Carbs are also linked to insulin spikes, and high insulin levels are a risk factor for insulin resistance. Insulin resistance is when your body has too much insulin and, as a result, can’t use glucose (aka the energy from carbs) for energy, which leads to increased blood sugar that puts you at risk for things like type-1 diabetes. (3)

Research has shown that strategically limiting your carb intake can improve insulin sensitivity or your body’s ability to utilize the hormone better. (4) Other studies suggest that employing both higher carb and higher fat days may help to regulate hormones related to appetite and improve the body’s ability to burn fat as a source of fuel. (5)

Who Should Carb Cycle? 

Carb cycling is recommended for recreational athletes, desk jockeys, weekend warriors, and anyone else who doesn’t need a constant stream of carbohydrates. So professional athletes and the obese are the two groups who probably shouldn’t employ this strategy. Dr. Jeff Golini, a nutritionist at Winner Circle Athletics, a Californian academy for youth athletes, explains why athletes may not benefit from carb cycling.

“Athletes burn up their glycogen stores very quickly. They have to be replenished with good, clean carbs regularly constantly,” he says. ”The reason why is that your off days are the days you’re recuperating, and taking in carbohydrates on your off days is almost more important than taking them on game days. The only so-called ‘cycling’ I’d recommend for athletes would be to focus on simple carbohydrates before training.”

As a reminder, simple carbohydrates are things like white breads and pastas, pastries, and sugar. These carbohydrates provide quick bursts of energy instead of complex carbohydrates (whole grains and brown rice), which provide energy over an extended period of time. 

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And the word “athlete” here refers to professionals or those training six days per week. People who are this active may not see many benefits from cycling carbs, Golini says.

“Now, if we’re talking about a weekend warrior or the person who just works out, that’s a whole different thing,” he adds. “Because depending on their goal, if they are trying to put on weight, then they probably don’t need to carb cycle. But if they’re trying to lose some body fat, then manipulating or cycling the carbohydrates is crucial.”

At least for a little while, there’s one other group that should avoid carb cycling: those with little experience tracking their calories. Counting each calorie and macronutrient (protein, carbs, and fats) is time-consuming and tedious. Carb cycling adds another layer of complexity. The strategy, then, may be more useful for folks who have experience and comfort with tracking their macronutrients than those who are new to dieting.

“[Carb cycling] may be confusing for some, and some may face adherence issues,” says Dr. Kalra. “If someone has binge eating tendencies, they should not do it as they can go overboard with the number of carbs and calories.”

It’s also worth emphasizing that carb cycling is usually used once a person is already pretty lean and/or muscular. Some studies have shown little benefit for overweight or obese people, for whom overall calorie intake should be a bigger focus. (6)

Sample Carb Cycling Routine

Like any other fat loss or strength-building strategy, there are different ways to carb cycle. However you want to tackle it, you must know how many calories you burn on a given day. This can take a lot of trial and error, but if you’re serious about body composition and carb cycling appeals to you, there’s no escaping it. 

That means you have to find out your total daily energy expenditure, or TDEE. You also use the calorie calculator below to find a rough caloric starting point. Once you find that out, consider the following carb cycling options as potential starting points.

Calorie Calculator

Activity Level
BMR estimation formula

Carb Cycling for Weight Loss

TDEE: 2,500 calories

Workout Day

  • Calories: 2,500
  • Protein: 180 grams (720 calories)
  • Carbs: 360 grams (1,440 calories)
  • Fat: 38 grams (340 calories)

Rest Day

  • Calories: 1,500
  • Protein: 180 grams (720 calories)
  • Carbs: 50 grams (200 calories)
  • Fat: 64 grams (580 calories)

If you exercise four days per week, the splits above should result in a pound of weight loss per week. While it’s usually used to lose fat, some people use carb cycling to gain muscle with minimal fat gain. You might keep calories at maintenance on rest days and limit your excess calories and carbs to lifting days with this goal. That might look like this:

Carb Cycling for Muscle Gain

TDEE: 2,500 calories

Workout Day

  • Calories: 2,995
  • Protein: 180 grams (720 calories)
  • Carbs: 400 grams (1,600 calories)
  • Fat: 75 grams (675 calories)

Rest Day

  • Calories: 2,500
  • Protein: 180 grams (720 calories)
  • Carbs: 85 grams (340 calories)
  • Fat: 160 grams (1,440 calories)

It’s crucial to note that recommendations for macronutrients vary considerably based on your body weight, body composition, and activity level. We strongly recommend consulting with a registered dietitian or a sports nutritionist before guessing at your ideal macros.

Can I Cycle Carbs on a Ketogenic Diet?

Carbs are usually kept to a minimum, or even zero, on the keto diet — so is carb cycling even possible when your goal is to limit them as much as possible? It’s possible, though there’s not much research behind the idea. 

Lean man eating rice
Ajan Alen/Shutterstock

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Doing keto one day and high carb the next would be too dramatic a fluctuation in carb intake and would interfere with ketosis itself, which can take over a day to kick in truly. Athletes who do a cyclical ketogenic diet often have 24 to 48 hours of “refeeding”: or eating high-carb, lower-fat meals. Then they switch back to a ketogenic split (high-fat, low-carb, medium-protein) for the rest of the week. This may help to fill muscle glycogen stores and improve athletic performance.

“Sometimes, cycling carbs helps maintain sustainability in individuals on a ketogenic diet,” says Dr. Kalra. “It can be an empowering approach for athletes or anyone who is into fitness as they can time a higher intake of carbs around exercise or HIIT.”

Final Word 

Controlling your calorie intake, regardless of macronutrients, remains the most important component of a weight loss plan. Maintaining a relatively high protein intake, whether you’re trying to lose fat or gain muscle, is widely considered to be fundamental as well.

But for people who are already quite lean and muscular who want to take their fat loss to the next step, carb cycling may be a useful tool. Ensure you speak to your physician or a dietitian before forging ahead with any new weight loss plan.


What is Carb Cycling?

Carb Cycling, as the name implies, is when you cycle through high-carbohydrate and low-carbohydrate eating days. The goal is to reduce food intake on the days you’re less active, which will help facilitate fat loss.

Should anyone not cycle their carbs?

Yes. Professional athletes, or anyone who works out every single day, should consume a steady amount of carbohydrates. These ultra-active folks use and require a lot of quick-burning fuel in the form of carbohydrates. Otherwise, they’ll feel sluggish and potentially lose muscle mass.

Can I carb cycle on the Ketogenic diet?

Yes, but your carbs are already so low, there’s not too much of a point. Plus eating carbohydrates will kick you out of ketosis. Though, some people have a high-carb day during the week once in a while to improve performance.


  1. McConell G, Kloot K, Hargreaves M. Effect of timing of carbohydrate ingestion on endurance exercise performance. Med Sci Sports Exerc. 1996 Oct;28(10):1300-4. doi: 10.1097/00005768-199610000-00014. PMID: 8897388.
  2. Coyle EF. Timing and method of increased carbohydrate intake to cope with heavy training, competition and recovery. J Sports Sci. 1991 Summer;9 Spec No:29-51; discussion 51-2. doi: 10.1080/02640419108729865. PMID: 1895362.
  3. Wilcox G. Insulin and insulin resistance. Clin Biochem Rev. 2005;26(2):19-39.
  4. Kinzig KP, Honors MA, Hargrave SL. Insulin sensitivity and glucose tolerance are altered by maintenance on a ketogenic diet. Endocrinology. 2010;151(7):3105-3114. doi:10.1210/en.2010-0175
  5. Kresta JY, Byrd M, Oliver JM, et al. Effects of diet cycling on weight loss, fat loss and resting energy expenditure in women. J Int Soc Sports Nutr. 2010;7(Suppl 1):P21. Published 2010 Sep 15. doi:10.1186/1550-2783-7-S1-P21
  6. Hall KD, Bemis T, Brychta R, Chen KY, Courville A, Crayner EJ, Goodwin S, Guo J, Howard L, Knuth ND, Miller BV 3rd, Prado CM, Siervo M, Skarulis MC, Walter M, Walter PJ, Yannai L. Calorie for Calorie, Dietary Fat Restriction Results in More Body Fat Loss than Carbohydrate Restriction in People with Obesity. Cell Metab. 2015 Sep 1;22(3):427-36. doi: 10.1016/j.cmet.2015.07.021. Epub 2015 Aug 13. PMID: 26278052; PMCID: PMC4603544.

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