A diet or training plan suitable for someone looking to lose weight may not be good for those looking to pack on muscle — but is that the case with carb cycling? The practice of alternating high- and low-carb days has been used by nutrition experts worldwide to help people shed weight — so you’re probably curious if it could have the opposite effect.
And the answer — eh, the science is a little shaky. Still, if you’ve reached a bodybuilding or powerlifting plateau, using this strategy might not be the worst idea in the world. But just as carb cycling should only be attempted by those with experience in tracking calories and macronutrients, dieting newbies should probably steer clear of this technique for now.
What is Carb Cycling?
If you’re new to the world of carb cycling, here’s a quick crash course (it’s nice to have a refresher either way). Carb cycling is the practice of alternating high-carb and low-carb intake days. So one day, you eat a lot of carbs, usually during intense training days, and the next day only a few grams, on lighter training or rest days.
People usually employ the strategy to change their physique based on aesthetic goals, as muscles tend to look “fuller” after consuming many carbs.
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Overall calorie intake is often higher on high-carb days, and that will probably be the case if you’re looking to gain muscle for bodybuilding and powerlifting. One’s protein intake remains the same across all days, while fat intake can change from day to day.
And there’s research to back up its practice. Studies have shown that timing carbohydrates around workouts may help optimize physical performance — aka how well you do in the gym — and recovery afterward. (1)(2)
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)
How to Carb Cycle for Muscle and Strength Gain
Before you attempt carb cycling, you’ll need to know how many calories to eat to be in a surplus. Again, not that we have to tell you this, but those looking to build muscle should eat 200-300 extra calories per day. But if you, for some reason, don’t have it, you can use our handy calorie calculator to find out.
A dietitian or nutritionist will design your diet plan for you, and they may also alternate days when you’re in a caloric surplus versus a caloric deficit. Some may even keep you in a caloric surplus every day and alter your macronutrients to switch up the number of carbs. In contrast, others may introduce “moderate-carb days” where your carbs, and total calories, will be what you need to maintain your weight.
High-carb days are to fuel rigorous workouts — you can’t build muscle without pumping plenty of iron. As we mentioned before, tailoring your carb intake around your workouts may help you eke out a few extra bench press reps, which, of course, leads to more muscle. It’s also used to fill muscle glycogen stores, make muscles seem fuller, and reduce muscle breakdown. (4)
High-carb days have also been known to help boost hormone levels, including testosterone — which can help improve performance in the gym and hold onto quality muscle as you continue to age. (5)
The low-carb and possibly low-calorie days help you achieve a few things: We already touched on how it will help insulin sensitivity, but it can also help you burn fat without sacrificing muscle. On these days, your body will learn how to burn fat — similar to how it does in a state of ketosis — rather than carbohydrates, which could make your muscles seem smaller or even break them down slightly. (6)(7)
One other note: carb cycling while gaining muscle will be useless if your protein isn’t dialed in. That means your protein macronutrients have to be at a point where it supports your body putting on extra muscle — and that’s a number you and your nutritionist will figure out. (8) Though, you can also check out our protein calculator below to find a starting point.
Protein Intake Calculator
Should Bodybuilders or Powerlifters Try Carb Cycling?
While there’s plenty of proof that carb cycling can help you build muscle, it’s unclear whether it should be used by people trying to do it for a living. Dr. Jeff Golini, a nutritionist at Winner Circle Athletics, a Californian academy for youth athletes, told BarBend for a prior story why it may not be best for people who work out regularly.
“Athletes burn up their glycogen stores very quickly. They have to be replenished with good, clean carbs regularly, constantly,” Golini 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.”
And the word “athlete” here refers to professionals or those training six days per week. People 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 carbohydrates is crucial.”
Some studies have shown carb cycling has little benefit for improving muscle circumference. Instead, increasing the overall calories was the only difference in increasing muscle size. And one can still increase their calories while alternating carb intake. (9)
Bodybuilders typically cycle through a bulking phase and a leaning-out phase. While trying to gain mass, they may want to keep carb intake high, Golini implies. As the research referenced above shows, cycling carbs while trying to lean out could help lower their overall calories while helping to retain muscle mass.
Powerlifters may have an even harder time, as studies have shown carbohydrate consumption is vital before, during, and after intense training sessions. And they’re equally as vital on rest days to promote recovery, meaning having a low-carb day may not be beneficial in the end. (10)
Cycling Types of Carbs
Until there’s more evidence on whether carb cycling works for bodybuilders and powerlifters, there’s another strategy they may want to consider — cycling types of carbs. As a reminder, there are simple and complex carbohydrates.
Simple carbohydrates consist of items like white bread and pasta, pastries, and sugar that provide quick bursts of energy that are depleted in a short amount of time. Complex carbohydrates — whole grains and brown rice — provide energy over an extended period of time.
Both types have their benefits, though complex has more pluses than simple. These types of carbs not only provide sustained energy — meaning you’ll need to eat less food to feel energized — but they also help control blood sugar levels, preventing hunger pangs and preventing conditions such as type 2 diabetes. Simple sugars, on the other hand, can exacerbate these conditions. (11)
So why would anyone want to go with simple carbs, to begin with? Again, they provide quick bursts of energy — great for something like slamming weights for an hour or two, right? Simple carbs are also the best choice for quickly getting some glycogen into your muscles, though the energy won’t last for very long (12).
If bodybuilders did want to try to cycle carbs, they could do so with these two types of carbs. Some may use simple carbs before a workout for the energy, and some may schedule it after for a good pump — that’s a decision you and your nutritionist will make. But you’ll want to have most carbs come from the complex type to promote good health and recovery.
When it comes to building muscle, reaching your protein intake is the most important component overall. That said, carbohydrates play an important role in providing energy and making your muscles appear rounded and strong.
For some who have reached a muscle-building plateau, playing around with when you eat a high amount of carbs and when you eat a small amount could help you make new gains. Ensure you speak to your physician or a dietitian before forging ahead with any new diet 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.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.
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