Nutrition
for lifters.

Training builds the stimulus; what you eat decides whether it turns into muscle. These are plain-English guides to the parts that actually matter — calories, protein, deficits and surpluses — without the noise.

Checkfit programs and progresses your training. Your nutrition stays in your hands — these guides are here to make that side straightforward.

17 guides

Bulking vs. Cutting: Which Should You Do First?

It depends on your body fat. Carrying more fat? Cut first. Already lean and want to grow? Bulk slowly. A plain framework for choosing, plus how to run each.

How to Lose Fat Without Losing Muscle

A calorie deficit costs you weight — protein and lifting decide whether it's fat or muscle. The three rules that keep your hard-won muscle through a cut.

Why You're Not Losing Weight "In a Calorie Deficit"

If the scale won't move, you're almost certainly not in the deficit you think you are. The four reasons it happens — and the one fix that settles it.

How Big Should Your Calorie Deficit Be?

Bigger isn't better. The right deficit is the one you can hold while keeping muscle — usually 0.5 to 1% of bodyweight per week. Here's how to set yours.

What Is a Calorie Deficit, and Why Is It the Only Thing That Burns Fat?

Fat loss has one non-negotiable: eating fewer calories than you burn. Here's what a deficit actually is, why nothing works without it, and how to run one.

How Much Protein Do You Actually Need to Build Muscle?

The consensus range is 0.7–1 gram per pound of bodyweight daily. How to hit it from food, when to aim higher, and what actually doesn't matter.

Strength Training for Fat Loss: Why Lifting Beats Endless Cardio

In a calorie deficit, lifting decides whether you lose fat or just lose weight. Why strength training protects muscle that cardio can't.

Diet Breaks and Refeeds Explained

A diet break is a planned week or two at maintenance in the middle of a cut; a refeed is a short one-to-two-day rise in calories. Both give you a physical and mental breather from a deficit and can make dieting more sustainable.

Reverse Dieting: What It Is and When to Use It

Reverse dieting means gradually raising your calories after a diet to return to maintenance without rapid fat gain. It's useful for a controlled transition off a cut, but it won't 'repair' your metabolism the way it's often sold.

Body Recomposition: Building Muscle While Losing Fat

Yes, you can build muscle and lose fat at the same time — it's called recomposition. It works best for beginners, returning lifters, and those with fat to lose. Eat at or slightly below maintenance, keep protein high, and train hard.

Maintenance Calories: How to Find Yours

Your maintenance calories are the amount that keeps your weight stable. Estimate with a calculator, then correct the estimate by tracking your intake and weight for two to three weeks. The scale is the real answer.

The Best Protein Sources for Building Muscle

The best protein sources are lean meats, fish, eggs, dairy, and — with a little planning — legumes and soy. Prioritize sources that are high in protein per calorie and that you'll actually eat consistently.

Protein Timing: Does It Actually Matter?

A little. Spreading protein across three to five meals is modestly better than cramming it into one, but your daily total dominates. Hit the total first; treat distribution as a minor refinement.

Post-Workout Nutrition and the Anabolic Window

The anabolic window is real but far wider than the old 30-minute rule. Eat a normal protein-containing meal within a few hours of training and you're covered. Your daily totals matter more than the clock.

What to Eat Before a Workout

Eat a normal meal with carbs and protein one to three hours before training. If you're training fasted or short on time, that's fine too — total daily intake matters far more than pre-workout timing.

Do You Actually Need Supplements to Build Muscle?

No. You need enough protein, enough total calories, and consistent training. A short list of supplements can help at the margins, but none is required to build muscle.

Creatine: What It Does and How to Take It

Creatine monohydrate helps you do slightly more work in the gym, which adds up to more muscle over time. Take 3–5 grams a day, every day, with no loading phase required.

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