Muscle Growth Calculator for Women

What Is a Muscle Growth Calculator?

The muscle growth calculator is a digital tool that helps determine your nutritional requirements for effective muscle growth. Below, we discuss how it works and why it’s essential for women over 40.

How It Works: From BMR to Surplus

The muscle growth calculator uses information including age, weight, height, and physical activity to determine your basal metabolic rate (BMR), which is your daily calorie allowance.

Using your BMR, the calculator then applies a calorie surplus. Research shows that a calorie surplus can provide a higher carbohydrate intake, which may fuel higher volumes of resistance training, promoting greater growth. This surplus also allows for a greater protein intake, increasing growth.

Why It Matters for Women Over 40

Women over 40 experience a decline in the reproductive hormone estrogen. This results in a hormonal imbalance that affects different areas of the body, including a significant decline in muscle mass and bone density.

Studies show that age and the decline of estrogen are associated. Before the decline of estrogen, protein synthesis and protein degradation occur, resulting in effective protein turnover, a process vital to muscle protein synthesis and the health of muscle tissue.

However, as estrogen declines, muscle protein turnover can become dysregulated, placenta greater shift toward degredation, which contributes to muscle fiber atrophy and loss of force generation.

During this time, bone mineral density declines. Research shows estrogen is a key regulator of bone metabolism and bone turnover. Sadly, when it declines, it can lead to a decrease in bone mineral density and increase the risk of osteoporosis.

Furthermore, sources show that mechanical stimuli in the form of gravity and muscle contractions are major contributors to bone health.

The decline of muscle contractile force and estrogen decreases can severely impact bone mineral density. This can contribute to the loss of strength and function, while increasing frailty and the risk of falls.

Inputs You’ll Need

The muscle growth calculator works with basic information to determine your nutritional requirement to support muscle growth. Below are these requirements, including basic data, training details, and bone health considerations.

Basic Data: Age, Weight, Height, Activity

Basic information, including your age, weight, height, and physical activity, is required to determine your basal metabolic rate (BMR). Below is a brief example of each to highlight how they influence your BMR:

• Age: Metabolic rate declines with age, decreasing energy expenditure.
• Weight/Height: Larger bodies have greater energy expenditure.
• Activity: The type of physical activity, intensity, and duration influence your energy expenditure and your daily requirements.

Training Details & Bone Health Considerations

As mentioned, the training factors, including the type, intensity, and duration, have a major influence on your daily calorie allowance. Here, the longer the duration and the greater the intensity, the more energy is expended.

Bone health will also be considered, as it is one of the major reasons for muscle growth for women over 40.

Recommended Calorie Surplus for Muscle Growth

A calorie surplus is required for muscle growth, providing your body with additional protein for muscle growth and carbohydrates to fuel your workouts.

However, this does not give you a license to eat indiscriminately. Here, we strongly recommend that you fuel your body with nutrient-dense carbohydrate and protein sources to increase muscle mass without the unnecessary weight gain.

Below, we discuss a safe calorie surplus and how to make adjustments based on progress.

Safe Surplus Range (200–400 kcal/day)

A calorie surplus of approximately 200–400 kcal/day is a safe starting point for gaining muscle. Small increases allows you to gradually increase muscle mass and monitor changes, while lowering the risk of unwanted weight gain.

Furthermore, eating an additional 400 kcal per day can challenging. Here small increase, you allows the body to adjust, reducing the feelings of discomfort.

Adjusting Based on Progress

Building muscle is rarely a set and forget, requiring careful tracking, adjusting, and reassessing to achieve our goals.

During the process you will experience, your body will undergo a recomposition where you will lean muscle tissue will increase and fat mass will decrease. However, this is rarely straightforward, as weight and performance fluctuate. During these moments, adjustments to nutrition and training can help overcome these slumps.

Now, this doesn’t mean going off-plan at the first slump or sign of resistance, but rather performing calculated adjustments. To achieve this, we recommend training through the plateau, in line with your current training block (e.g., 6–8 weeks).

During this time, we recommend focusing on increasing intensity and volume during sessions and focusing on recovery, sleep, and nutrition. If, after the training block (6–8 weeks) there is still no progress, consider a change of exercise or increasing calorie intake. This will help provide another stimulus and additional protein and carbohydrates to fuel your sessions and promote growth.

Macro Targets: Protein, Carbs, and Fat

Monitoring macronutrient intake is essential when building muscle, ensuring that you have enough carbohydrates to fuel intense training sessions and protein for muscle growth and recovery.

Below, we list a common macronutrient ratio for building muscle:

• Carbohydrates: 40% of total daily calories
• Protein: 30% of total daily calories
• Fat: 30% of total daily calories

Using this ratio, we will show you how these additional 200-400 kcal/day will be divided:

As you can see, this increase provides significantly more carbohydrates to fuel workouts and protein to aid in growth and recovery. Furthermore, this also provides an additional 7–13g of fat, which will help support hormone balance and several other systems in the body.

Protein Needs (1.6–2.2 g/kg)

Studies show the recommended daily protein intake for healthy individuals is 0.8 g/kg/day. However, if we want to increase muscle mass, this needs to increase. Here, research shows that 1.6–2.2 g/kg of body weight is required to maximize muscle growth.

Below is an example of protein requirements for a 70 kg healthy individual and a 70 kg individual looking to maximize muscle gains.

• 0.8 g/kg x 70 kg = 56 gram per day
• 1.6–2.2 g/kg x 70 kg = 112–154 grams per day

As we can see, this is a significant increase. The prescribed 56 grams for a healthy individual is a relatively small target. Meanwhile, 112–154 grams per day doubles and even triples intake, presenting a challenge for those who already struggle to hit their daily protein goals.

For reference, here is a list of high-protein foods that can help you hit your daily protein targets.

As you can see, there are several foods, specifically meats, which can make up more than half of the daily protein intake for the standard allowance.

However, it is important to note that while some sources, such as are high in protein, they are also calorie-dense. To avoid blowing through your daily calorie intake, we recommend sticking to the recommended serving size

For individuals aiming to maximize muscle growth, it will take more effort. To hit those higher targets, we recommend adding a minimum of 25 grams to each meal.

Carbohydrate & Fat Distribution

Carbohydrates and fats make up an important part of your dietary intake. As mentioned, carbohydrates are essential, providing fuel for increasing training volume and performing at a higher intensity.

Carbohydrates are one of the body’s primary energy sources. Research recommends consuming 4–7 g/kg day for hypertrophy. Meanwhile, studies recommend 0.5–1.5 g/kg/day of dietary fats.

Below is a quick example of each for a 70 kg woman:

• Carbohydrates:  4–7 g/kg/day x 70 kg = 280–490 g/day
• Fats: 0.5–1.5 g/kg/day x 70 kg = 35–105 g/day

These should be consumed as complex carbohydrates and healthy fats. Research shows that complex carbohydrates contain three or more sugars bonded together. This means they take longer to digest, providing a gradual increase in blood sugar.

Meanwhile, sources show that healthy fats such as omega-3 fatty acids are incredible, supporting cardiovascular health, brain function, and reducing the risk of chronic disease.

How to Use the Calculator Output

Once you have calculated your daily calorie allowance, it will need to be divided into macronutrients using your desired macronutrient ratios.

Here we will use the example of 2,000 kcal/day using the following macronutrient ratio:

• Carbohydrates: 40% of daily calorie intake
• Protein: 30% of daily calorie intake
• Fats: 30% of daily calorie intake

This can be divided using a calculator or a nutrition tracking app.

• Carbohydrates (40%): 200 g
• Protein (30%): 150 g
• Fat (30%): 67 g

Below, we will use this data to plan meals and hit macronutrient targets to pair with resistance training.

Planning Meals & Macronutrient Targets

Planning meals using the above information can be challenging, especially with a variety of ingredients. To simplify things, we recommend using a nutrition tracking app. These allow you to select your macronutrient ratios, which then easily divide your daily calorie allowance into macronutrient targets.

For example, using the 2,000 kcal/day and macronutrient ratio above, we will divide these across four meals. Main meals tend to be larger, so we will allocate 550 kcal, with the snack containing 350 kcal.

Using this information, you can plan your meals. When attempting to increase muscle mass, there should be a big focus on protein intake. As you can see, this table clearly shows that you should be adding 41 g for main meals and 26 g for your snack.

Tracking your nutrition can be challenging in the beginning. However, over time, you will end up with a list of commonly eaten foods for which you will know the exact serving size, calorie, and macronutrient content. When this is combined with a nutrition tracking app, it streamlines the entire process.

Pairing With Resistance Training

Studies show that resistance training can develop strength and stimulate hypertrophy (muscle growth). Muscle hypertrophy occurs when protein synthesis exceeds muscle protein breakdown, which can be achieved with resistance training and protein intake.

Research shows that performing resistance training and progressively overloading muscle tissue by increasing resistance, sets, repetitions, and intensity can promote muscle growth.

For adequate stimulus, we recommend performing three resistance training sessions per week. This will allow you to still have sufficient rest between training sessions for recovery and growth.

Summary & Call to Action

Muscle Growth Recap

Building lean muscle is incredibly rewarding. Not only does it provide with the feeling of enhanced strength and function, it also helps to preserve bone mineral density and quality of life.

By combining a calorie surplus and sufficient protein with three resistance training sessions per week, you can make major gains for your physical health.

Why This Calculator Helps You

Correct nutrition is essential for building strong, lean, functional muscle mass. Using our calculator will outline your daily calorie and macronutrient breakdowns, providing you with dialy targets that will help you reach your short- and long-term goals.

Try the Tool Now & Start Smart Strength Gains

Kickstart your muscle growth now using our muscle growth calculator and receive your exact calorie and macronutrient breakdown!

Sources

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