I lost some strength after taking a break from resistance training

Those 60s felt a lot heavier. I was struggling…

I love resistance training. Over the past 4 years, I haven’t taken a substantial break from training. Of course, there were loopholes - not getting adequate recovery all the time, being on point with nutrition and not pushing myself hard enough. But I tried to go to the gym consistently; the vibe and the atmosphere made me happy.

Last year, I had to take a break for about 3 weeks in December. During the break, my diet and sleep were way off the charts. Disappointed? A tad. When I resumed training, I knew I wouldn’t be able to lift the same amount of weights. I decided to dig around a bit to understand how exactly the break affected my muscle gain and strength. Here’s what I found out.

Before we dive in, you need to understand how exactly your muscles adapt to resistance training and increase in mass.

Your body always likes to be in a predictable state. When you start resistance training, your muscle fibers undergo stress disrupting this stable state. This state is referred to as a homeostasis. (It is a self-regulating process through which an organism can maintain internal stability while adjusting to external changes) Think of it as a coping mechanism. For example, when your body fluid level goes down, you feel thirsty and you drink water. When your blood sugar level goes down, you feel hungry.

When you consistently exercise, your body is forced to adapt to the external stress (stimuli) due to homeostasis mechanisms. The harder you work out, the more stimulus you provide.

Resistance training induces three types of stress (stimuli) on the muscles [1]:

• Mechanical tension - The force the muscles experience when they contract against resistance. For example, let’s say you are doing a bicep curl for 6 reps. The first two reps would be easy, the next two would be harder and the last two reps will move very slowly. This means, your bicep muscle fibres have experienced the greatest mechanical tension during the last two reps. Over recent years, studies suggest that mechanical tension is the biggest driver for muscle growth.

• Metabolic stress - Imagine it like the "burn" you feel during intense exercise. It's caused by lactic acid buildup and other byproducts in your muscles.

• Muscle damage - During intense exercise, microtears occur in your muscle fibres. Your body repairs these micro-tears by building new, stronger muscle fibres in their place

Two processes contribute to muscle building. Muscle Protein Breakdown (MPB) and Muscle Protein Synthesis (MPS). Muscle protein breakdown happens continuously in our body. It is the degradation of muscle proteins into amino acids. On the other hand, muscle protein synthesis is the metabolic process that produces muscle protein during recovery. It works in opposition to muscle protein breakdown.

Resistance training-induced stress, especially mechanical tension increases the rate of muscle protein breakdown and stimulates muscle protein synthesis. You also maximise muscle protein synthesis with high-quality protein intake from your diet since your body cannot produce essential amino acids on its own.

Put simply, muscle growth (known as hypertrophy) happens when MPS > MPB. If MPB > MPS, muscle loss happens.

On a macroscopic level, to grow muscles, you need to fundamentally do 2 things. Train hard, eat high-quality protein. Of course, other nuances also help build muscle, like increasing carbohydrates [3], getting a sufficient amount of sleep [4], and so on. But let’s not dive into those for now.

Now that you have understood how we build muscles, (I am assuming) let’s try to decode what exactly happened to my strength due to the break from training.

When you take a substantial break, your muscle strength decreases due to three main factors:

Muscle atrophy: When you stop stimulating your muscles through exercise, they start to shrink (atrophy). [5] This happens because muscle protein synthesis (muscle building process) slows down while muscle protein breakdown (muscle breakdown process) continues. The rate of atrophy depends on various factors like your training experience, the length of your break, and your overall nutritional status during that period.

Neural adaptations: Resistance training also leads to adaptations in your nervous system, allowing you to recruit more muscle fibers and generate more force. When you stop training, these adaptations start to reverse, making it harder to activate your muscles effectively. [6]

Connective tissue changes: During training, your tendons and ligaments also adapt to the increased forces. Taking a break can lead to these structures becoming less stiff and resilient, potentially impacting your strength and stability. [7]

Several other factors like the duration of the break, training history and experience, age, activity level, diet and nutrition, sleep, and genetics also influence how quickly you lose muscle and strength when you take a break from resistance training.

However, even with some muscle loss during a break, you can regain strength and size much faster than when you first started training due to a very interesting concept called muscle memory (a form of procedural memory). The concept of muscle memory will be broken down in another blog soon.

Stay hydrated! ⚡️

References:
1. The mechanisms of muscle hypertrophy and their application to resistance training. PMID: 20847704
2. https://www.e-agmr.org/journal/view.php?doi=10.4235/agmr.20.0041
3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8878406/
4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5749041/
5. https://www.sciencedirect.com/science/article/pii/S0531556519307806
6. https://pubmed.ncbi.nlm.nih.gov/3057313/
7. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1164074/