What is carb cycling?

Carb cycling alternates higher- and lower-carbohydrate days within the week, so you eat more carbs on hard training days and fewer on rest days.

Does carb cycling work?

For weight loss, total weekly calories matter more than how you spread them across days. Some lifters find that more carbs on training days helps their sessions, and find the pattern easier to stick to, which is how it helps fat loss.

How do I choose between the three patterns?

High-low is the simplest: alternate high and low days. Training-rest follows your gym schedule. Three-tier adds a medium day, for programs with heavy, moderate and rest days.

Why does protein stay constant across day types?

Your protein need depends on your body weight and training, not on the day’s calorie target. MuscleBuddy holds it at 2.2 g/kg on every day of the cycle, high or low.

Why does fat change between days?

Fat fills the calories left after protein and carbs. On high-carb days carbs take more of the budget, so fat drops; on low-carb days fat rises. Fat stays at 20% or more of the calories on every day.

Is carb cycling the same as keto?

No. Keto keeps carbs low every day to stay in ketosis. Carb cycling puts high-carb days (often 200 g or more) on training days, which ends ketosis. A cyclical ketogenic diet combines the two, but that is a different plan from this one.

How do I decide which days are "high" or "low"?

Match high-carb days to your hardest training sessions (heavy compound days, long sessions). Match low-carb days to rest days or light cardio days. The in-app carb-cycling planner maps these to your program's training days.

Carb cycling planner

Free carb cycling planner: build high and low carb days from your base calories and protein floor. Supports high/low, training/rest, and three-tier patterns.

Carb cycling alternates higher- and lower-carbohydrate days so more of your carbs land on the days you train hardest. Heavy training days get more, rest days get fewer, and rest days run a little lower in calories to pay for the training days. Your weekly calorie average stays at your target; the planner only moves carbs and calories between days.

This planner builds a day-type macro template from a base calorie target, your protein and fat floors, and one of three patterns: simple high-low alternation, training-vs-rest scheduling, or a three-tier high-medium-low rotation. Protein stays the same on every day type. Fat moves opposite carbs so each day still adds up to its calorie target.

Base calories

kcal

Daily protein

Baseline fat

Pattern

Per-day macro template (training / rest)

training day

Calories2644 kcal

Protein180 g

Carbs341 g

Fat62 g

rest day

Calories2140 kcal

Protein180 g

Carbs114 g

Fat107 g

How this works

The math starts with three inputs: base calories (your maintenance or goal-calorie target, averaged across the week), protein grams (held constant at 2.2 g per kg of body weight), and fat grams (your everyday baseline, typically 60–80 g).

Once protein and fat are locked, the calculator works out the base carb target by subtracting protein and fat calories from the daily calorie budget. Then it applies a multiplier per day type to shift carbs up or down:

High-low: high days run +30% carbs at +10% total calories; low days drop to 50% of base carbs at 85% of base calories.
Training-rest: training days hit 120% carbs at 105% calories; rest days fall to 40% carbs at 85% calories.
Three-tier: high days at 150% carbs / 115% calories, medium at baseline, low at 30% carbs / 85% calories.

These percentages are relative. The planner scales the calorie and carb figures together so the week averages your base calories and your base carbs. Fat is then worked out from each day's calories, with a 20 g minimum, so every day adds up. Protein stays fixed because your need for it doesn't change with the day's training.

Day scheduling: put high-carb days on your hardest sessions, such as heavy leg or back days, and low-carb days on full rest or light cardio days. How many of each you get depends on how often you train; the week still averages your calorie target.

When carb cycling helps most: in a deficit, when your sessions suffer on low-calorie days. Moving 50–100 g of carbs onto training days can make those sessions go better without changing the weekly deficit. At maintenance or on a bulk there is less to gain, because you already have the calories to train well.

Frequently asked questions

What is carb cycling?: Carb cycling alternates higher- and lower-carbohydrate days within the week, so you eat more carbs on hard training days and fewer on rest days.
Does carb cycling work?: For weight loss, total weekly calories matter more than how you spread them across days. Some lifters find that more carbs on training days helps their sessions, and find the pattern easier to stick to, which is how it helps fat loss.
How do I choose between the three patterns?: High-low is the simplest: alternate high and low days. Training-rest follows your gym schedule. Three-tier adds a medium day, for programs with heavy, moderate and rest days.
Why does protein stay constant across day types?: Your protein need depends on your body weight and training, not on the day’s calorie target. MuscleBuddy holds it at 2.2 g/kg on every day of the cycle, high or low.
Why does fat change between days?: Fat fills the calories left after protein and carbs. On high-carb days carbs take more of the budget, so fat drops; on low-carb days fat rises. Fat stays at 20% or more of the calories on every day.
Is carb cycling the same as keto?: No. Keto keeps carbs low every day to stay in ketosis. Carb cycling puts high-carb days (often 200 g or more) on training days, which ends ketosis. A cyclical ketogenic diet combines the two, but that is a different plan from this one.
How do I decide which days are "high" or "low"?: Match high-carb days to your hardest training sessions (heavy compound days, long sessions). Match low-carb days to rest days or light cardio days. The in-app carb-cycling planner maps these to your program's training days.

Related tools

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