Bulking and Cutting: How to Do It Safely

If you’re serious about building muscle or reshaping your body, you've probably heard about “bulking and cutting”. They’re buzzwords in gym culture, but they’re more than just hype. Done correctly, they can help you build strength, gain muscle, and reveal definition. Done badly, they can lead to burnout, excess fat gain, or loss of hard-earned muscle.

This guide will walk you through what bulking and cutting actually are, why people do them, and how to do them in a way that’s safe, sustainable, and effective.

What is Bulking and Cutting?

The concept of going through a bulk and cut cycle is deeply ingrained in bodybuilding and fitness culture. When done properly, bulking enables you to build muscle, and cutting lets you reveal those gains in a lean, defined state.

The keys to doing it safely and effectively? Consistency, balance, quality nutrition, sensible training, realistic expectations, and listening to your body.

Bulking: The Build Phase

A “bulking” phase is when you put yourself through a calorie surplus in order to build size. Essentially, you deliberately eat slightly more calories than you burn each day to provide your muscles with enough energy and nutrients to grow. With regular resistance training, this surplus helps you gain muscle and strength. However, avoid excessive calories surplus (more than 500Kcl/day) to avoid unnecessary fat gain.

Cutting: The Shred Phase

A “cutting” phase is when you’re in a calorie deficit — the opposite of bulking. You eat fewer calories than you burn, with the aim of burning off excess fat while preserving muscle mass. The goal isn’t just to lose weight, but to lower your body fat percentage so that the muscles you’ve built show definition and shape.

Why Do People Bulk and Cut?

People bulk and cut primarily to change their body composition by increasing lean muscle mass (bulk), then reducing fat to reveal those gains (cut).

Other reasons include:

• Maximising muscle growth: surplus energy and resistance training can make for a better environment for hypertrophy.

• Boosting performance and strength: more muscle often means more strength and better performance in sports or daily life.

• Structuring progress: a bulking and cutting cycle gives clear phases and goals, helping maintain focus and consistency.

How to Bulk, the Right Way

If you decide to bulk, the key is balance. The goal is to gain muscle while limiting fat gain and avoiding other negative side effects.

1. Add a Modest Calorie Surplus

Find out roughly how many calories you need to maintain your weight, then aim to eat slightly above that. This can be found in your FitQuest results, where your daily intake is calculated from your BMI. To find your daily caloric intake, multiply this number by your level of activity. x1.2 (sedentary), x1.4 (lightly active), x1.7 (moderately active), x2.0 (active all day).

A good ballpark could be to add around 10-20% more than your maintenance calorie intake. This smaller surplus ensures slower, steadier gains, which tend to be more sustainable in the long term.

2. Prioritise Quality Nutrition

Because of how the body works, bulking usually comes with some fat gain, as the extra energy from the calorie surplus doesn’t just go to muscle. That’s why people often differentiate between a “clean bulk” and a “dirty bulk”.

A clean bulk improves the likelihood that the extra calories go towards muscle rather than fat. Rather than eating lots of junk food to build mass quickly, focus on nutrient-dense, wholesome foods such as:

• Plenty of protein—essential for muscle repair and growth

• Complex carbohydrates—fuel for workouts and recovery

• Healthy fats—plus a mix of vitamins and minerals

In contrast, a dirty bulk that’s high in processed or poor-quality food may lead to quicker weight gain, but is often mixed with significant fat accumulation and poorer health outcomes.

3. Lift Heavy and Progress Gradually

Bulking isn’t just about eating more; lifting heavy and regularly is what tells your body, “build muscle here”. Your muscles need to be challenged to grow, especially if you want those extra calories to go to lean mass.

Focus on a hypertrophy-style resistance training programme that consists of compound movements (like squats and deadlifts), progressive overload, and consistent training volume.

4. Keep Expectations Realistic

If you’re a beginner or have a lean build, muscle gain can come relatively quickly. But don’t expect dramatic jumps in size every month. Even with a perfect bulking approach, most of the gained weight will be a mix of muscle, fat, water, and glycogen.

A slow, controlled bulk is far more sustainable (and healthier) than aggressive bulks that push for fast growth at the expense of too much fat and stress on the body.

How to Cut Without Losing Muscle

Once you’ve built muscle and size, most people want to show it off. That’s where cutting comes in.

1. Create a Controlled Calorie Deficit

Rather than slashing calories, aim for a moderate deficit that’s enough to trigger fat loss, but not so drastic that your body starts breaking down muscle for energy.

Extreme calorie restriction may be tempting for quick results, but it often backfires: you lose muscle, feel weak, and end up stalling or harming long-term progress.

2. Maintain High Protein Intake

Protein is even more important during a cut. Aim for roughly 1.6-1.8 grams of protein per kilogram of body weight, or more depending on your training volume and size. This will help preserve lean muscle while losing fat.

At the same time, you need sufficient micronutrients like vitamins, minerals, and fibre, especially if you reduce your carb and fat intake. Try to eat plenty of whole foods, vegetables, lean protein, and wholesome carbs during your cut.

3. Keep Lifting and Use Cardio Smartly

Though your energy levels might drop, maintaining resistance training is essential as it signals to your body to hold onto muscle. A minimum of 1-2 resistance training sessions per week would be optimal.

Adding some cardio can help increase calorie burn, but don’t overdo it. Too much cardio plus restricted nutrition can sap strength and recovery.

4. Be Patient

Rapid weight loss can be tempting, but more often than not leads to unwanted muscle loss, metabolic stress, mood swings, and rebound weight gain once the diet eases.

A measured, gradual approach with a steady calorie deficit, adequate protein, and regular training gives you a better shot at preserving muscle while trimming fat.

Common Bulk-Cut Mistakes and How to Avoid Them

While bulking and cutting can be effective, they’re not without potential downsides, especially if done hastily or without care. If you commit to a bulk-cut cycle, there are some risks and potential mistakes you should be aware of:

1. Bulking or Cutting Too Aggressively

A large calorie surplus, especially one fuelled by low-quality foods, can cause rapid fat gain, sluggishness, and poor cardiovascular health. Rather than building mostly muscle, you may end up with excess body fat that becomes harder to cut later.

At the same time, drastically reducing calories might speed up weight loss, but it often comes with significant muscle loss, fatigue, hormonal disruptions, and reduced training performance.

To prevent these pitfalls, aim for a small, controlled surplus or deficit and prioritise quality foods, particularly protein. Keep lifting during your cut to signal your body to preserve muscle and avoid crash dieting at all costs.

2. Focusing Only on Weight 

A common mistake people make while bulking and cutting is watching only the number on the scale. Instead, track:

• Body measurements (waist, arms, chest, etc.)

• Strength and performance improvements in the gym

• How your clothes fit and how you feel

That way, you’ll know whether you’re gaining mostly muscle or picking up too much fat, and will be in a better position to adjust your calorie intake or training accordingly.

3. Getting Stuck in Endless Bulk-Cut Cycles 

Some people get stuck constantly bulking and cutting, chasing temporary aesthetic changes without long-term health or sustainable muscle gains.

Define clear goals for each phase and stick to realistic timelines. Monitor your body composition and adjust based on results rather than switching phases impulsively.

4. Neglecting Recovery, Sleep, and Lifestyle 

Even with perfect training and nutrition, inadequate sleep, chronic stress, or poor hydration can hinder muscle growth and fat loss. Overtraining without proper recovery increases your risk of injury and burnout.

Prioritise 7-9 hours of sleep, manage stress, hydrate well, and schedule rest days. Treat recovery as an active component of your bulking or cutting plan, not an afterthought.

Bulk and Cut Like a Pro, With The Gym Group

If you want to try bulking and cutting in a structured yet flexible way, with access to good equipment, supportive personal trainers, and a community of like-minded people, why not try a gym where you can build muscle and then define it, all under one roof?

If you’re ready to transform your body with a safe and effective bulk-and-cut cycle, there’s no better place to start than with The Gym Group. With flexible membership plans, well-equipped strength zones, and a welcoming atmosphere, you’ll find everything you need to bulk, lift, cut, and track your progress.