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  • Writer's pictureAdam

Can you build muscle in a calorie deficit?

A lot of people will tell you, yeah let’s focus on bulking up, and then let’s focus on cutting down.

Then to bulk up again after a few months of being lean!

This is of course an effective way to do it and ensures you’re maximising either goal.

You're really maximising the muscle you gain in your bulking phase and maximising fat loss in your cutting phase.

After all, the first law of thermodynamics is that if you are in a calorie surplus, you will be storing net energy, and if you are in a calorie deficit, you will be losing net energy.

Some people then get confused and think muscle gain cannot occur when you’re losing weight.

When in reality, it can.

Let me explain why/how this is possible.

First, it’s good to understand that fat and muscle are two separate systems. So, it’s possible to lose fat and at the same time, still build muscle from the progressive training stimulus along with sufficient protein through your diet.

In your body, 1kg of muscle is stored as approximately 1200 kcal and 1kg of fat is around 7,700kcal.

Muscle has less stored energy as it’s 75% water.

Now time to quote one of my favorite studies...

A 2016 study by LongLand et al. looked at 40 overweight men over a 4 week period.

All participants were recreationally active and were put through resistance training + HIT/SIT training (Supramaximial Intensity training) for a total of 6 sessions a week (2 of each session).

The participants were split in half, one group was given a high protein diet of 2.4g per kg of bw and the other, a lower protein diet of 1.2g per kg of bw.

Both groups were in a very high-calorie deficit of 40% over the 4 week period.

The higher protein group lost more fat mass and gained more muscle than the lower protein group.

The lower protein group still lost fat mass, but barely gained any muscle mass.

This demonstrates the need for a higher protein diet when looking to benefit from losing fat and building muscle.

Nothing is without resistance...especially in the fitness industry!

Some argue that in a calorie deficit there are reductions in mTOR and muscle protein synthesis (the two main drivers behind muscle growth), and there is research to support this.

However, in the same body of research, the decline in MPS was restored with a resistance training session followed by a post-workout protein feeding (15-30g).

Not everyone will experience results like this and it’s easier to build muscle in a deficit if you are one of the three:

  1. You are a beginner - in your first 1-2 years of lifting.

  2. You have a significant amount of body fat to lose - in this case you’ll lose stored body fat to fuel muscle growth.

  3. You’re detrained - coming off an injury or time out of training.

To maximise your results here you’ll need to keep your protein intake high 0.8g-1g per lb of bodyweight and don’t crash diet as tempting as it is, instead keep the deficit 20% or under.

The trick is to start small and see how your body adapts!

That is all for this post.

If you want to watch the full video, I have posted can below - if you do, be sure to like the video and subscribe!

Any questions, comment below.

Keep pushing your limits!



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