How long will it take to transform my body?

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How long will it take me to: see a transformation/lose weight/get abs/build muscle? This is the type of question we get asked very frequently as trainers. People want to know how long it’s going to take them to achieve their goals, and unfortunately the answer is a bit “how long is a piece of string?”

There are so many variables that will affect the outcome. However, in this article I will do my best to shed some light on some of the key factors that will influence the rate of progress that someone can achieve specifically for fat loss and muscle gain.

General Health

You have to fix the inside in order to fix the outside. General health has an enormous impact on your body’s capability to drop body fat and build lean muscle. Some of the key players in general health include, but are not restricted to:

Gut Health

The Gastrointestinal system has the biggest overall impact on all the other systems of the body. This is not to say that it is more important, it just has a broader impact. People say that you are what you eat. However, to be more accurate you are what you eat, digest, absorb, and don’t excrete. Many people have digestive issues such as insufficient stomach acid, an inability to produce sufficient digestive enzymes, leaky gut, IBS, constipation, and diarrhoea to name but a few. Issues with your GI health can affect your ability to extract the necessary nutrients from your food, your ability to prevent the absorption of pathogens or undigested food particles, or your ability to eliminate the appropriate waste. These issues can then ultimately affect your nervous system, immune system, ability to recover and your ability to utilise fat for energy and recover and repair muscle tissue.

Endocrine Health

Your endocrine system governs your hormones. These are chemical messengers that trigger various activities throughout your body. For example thyroid hormone tells the cells of your body to increase their activity and is one of the master regulators of your metabolism. Insulin tells certain cells to absorb glucose from your blood stream. Cortisol tells your body to increase blood sugar levels. People can have dysfunction in a number of these areas. Thyroid health can be negatively impacted by low calorie dieting. Thyroid health is also affected by disease and genetic conditions. Insulin health can be affected by poor diet and lifestyle choices which can result in less nutrients reaching your muscles, and increased fat storage. Cortisol can be excessively elevated by chronic stress, lack of sleep, and illness. Chronic, excessive cortisol tends to deplete muscle mass and encourage fat retention.
Your body does much of it’s repair and recovery work when you are asleep
Immune Health

Your immune system can become over worked due to poor diet, food sensitivities and allergies, poor gut health (75% of your body’s entire immune system is found in and around your GI system), and environmental toxins. This can result in inflammatory molecules being released around the body, an impaired ability to recover and poor overall health. Your immune system can also become imbalanced due to excessive stress and poor diet and lifestyle.

Body composition is strongly dependent on general health and you will not be able to optimise fat loss or muscular development with impaired health. Many of these issues are reversible or can be significantly improved, but this can take time.


I’ve already mentioned stress a couple of times above. Your autonomic nervous system is divided into the sympathetic nervous system (SNS) and the parasympathetic nervous system (PNS). The SNS takes care of high energy activities, stress, fight or flight and so on. The PNS takes care of calming, healing, soothing activities including digestion, immune activity, sleep, recovery and so on. When you activate one you automatically deactivate the other. Excessive stress keeps the SNS running high and inhibits the PNS. Symptoms include elevated cortisol, elevated blood sugar (potentially contributing to impaired insulin health), inhibited digestion, inhibited immune function, neural fatigue, impaired workouts and impaired recovery. Once again this will all negatively impact your attempts at fat loss and / or muscle growth.


You may have noticed by now that all these systems are interconnected and you can’t affect one without affecting the others. Lack of sleep is another form of stress and is exceptionally common. Your body does much of it’s repair and recovery work when you are asleep. A great deal of your growth hormone bursts occur when you are asleep. In addition to helping repair tissue, growth hormone is a powerful fat burner. Lack of sleep will also disrupt the hormones ghrelin and leptin, resulting in an increase in appetite. Cortisol levels will once again become elevated with lack of sleep. A high demand for cortisol can also result in an effect called pregnenolone steal, which results in low levels of testosterone.
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A trainee’s ability to train hard with good, safe technique will dramatically affect their body composition progress. All other things being equal a client who can squat, deadlift, chin up, military press and dip pain free, and with good form will progress much faster than a client who cannot perform these movements due to injury, restricted mobility, or poor coordination.

Frequency and Compliance With Training

Consistency is critical to achieving progress in the gym. A trainee who is able to train 4 times a week, who trains consistently, and dedicates themselves to training hard and improving technique will inevitably achieve better progress than someone who trains twice a week, frequently misses training sessions, and does not apply themselves in training.

Compliance With Diet

Your ability to stick consistently to your diet will depend on a number of factors including:

Your mindset – specifically a healthy relationship with food without a tendency towards emotional eating Your environment – having a strong support structure at home, whilst not essential, is hugely helpful Organisation, planning and time management

Rapid Transformations

When someone achieves a dramatic and rapid transformation they will have everything optimally set up and in place right from the start. They may be overweight, or under muscled, but their general overall health is good, they move well and are able to train hard, safely and effectively with the big lifts, they train frequently and consistently and they have the mindset, environment, and organisational skills to stick to their diet consistently over the long term.

Choose a Sensible Goal

Broadly speaking you have the choice of one of the following goals:

A: Rapid weight gain (with the acceptance of substantial fat gain)

B: Muscle gain with a minor emphasis on fat retention or loss

C: Maintenance

D: Fat loss with a minor emphasis on muscle retention or gain

E: Rapid weight loss (with the acceptance of substantial muscle loss, and potentially harmful effects to your metabolism)

It should go without saying that it makes sense to prioritise either goal B or goal D if you want long term, sustainable results.
Consistency is critical to achieving progress in the gym
Reasonable Rate of Fat Loss

Assuming that you are normally healthy and compliant with your training and diet, the rate of progress that you can expect in terms of fat loss, if you are targeting goal D, is illustrated in the tables below. It’s important to recognise that these are very general guidelines. Some people will be slower than this, and some people will be faster than this, but these are useful figures for managing reasonable expectations.
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Reasonable Rate of Muscle Gain

For a normally healthy, compliant client focusing on goal B, the following guidelines are reasonable for establishing initial expectations on rate of muscle growth:
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Take Home Points

Rate of fat loss and muscle growth are dependent on many factors including:

1. General health, including but not limited to gut health, endocrine health, immune health

2. Stress

3. Sleep

4. Ability to move and train

5. Frequency and compliance with training

6. Compliance with diet

So many of these factors cannot be predicted so we are unable to specify how quickly a client will achieve their goals until they have been training with us for a while and we get to learn their abilities, habits, health, application and so on. For normally healthy, compliant clients, the tables above show reasonable rates of progress for managing initial expectations.

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