How Much Muscle Can You Gain? (& What Causes Growth?)

Summary

This video dives deep into muscle hypertrophy, examining both short- and long-term muscle gains from resistance training. It highlights how training status, fat-free mass, and gender affect muscle growth, with data from studies on male and female lifters. The review discusses key factors like mechanical tension, metabolic stress, and hormone fluctuations, while debunking myths about the role of acute hormonal spikes in hypertrophy. The video emphasizes the importance of consistent, scientifically-backed training for long-term muscle gains, touching on the nuances of responsiveness and the value of tools like the Alpha Progression app for personalized programming.

Takeaways

• 😀 Resistance training can lead to an average muscle gain of 1.5 kg of fat-free mass over 10 weeks in healthy adult males.
• 😀 Trained individuals tend to experience lower increases in muscle mass compared to beginners, though the difference is not always statistically significant.
• 😀 High responders to training may gain up to 21 kg of fat-free mass over their career, while low responders may only gain around 5 kg.
• 😀 Females gain muscle at a similar relative rate to males, but their absolute muscle gains tend to be lower due to starting with less muscle mass.
• 😀 The typical long-term fat-free mass increase for males is estimated to be 12.5 to 20.2 kg over 5 years, depending on responsiveness.
• 😀 Testosterone, even at normal levels, has been shown to increase muscle size significantly, especially in combination with resistance training.
• 😀 Temporary increases in systemic anabolic hormones (like testosterone, growth hormone, and IGF-1) following exercise are not strongly correlated with hypertrophy.
• 😀 Mechanical tension, or the force generated by muscle fibers, is considered the primary driver of hypertrophy during resistance training.
• 😀 Training close to failure can maximize mechanical tension and muscle fiber activation, but training to failure is not always necessary for muscle growth.
• 😀 Metabolic stress (e.g., lactates, hydrogen ions) is not the primary driver of hypertrophy, as studies show similar growth from low-rep and high-rep training.
• 😀 The 'pump' or cell swelling, although enjoyable, does not directly cause hypertrophy, and more research is needed to understand its potential benefits.
• 😀 Muscle damage has not been conclusively proven to be a key factor in hypertrophy, despite its common association with muscle growth.

Q & A

How much muscle can you expect to gain over the long term?

The average gain in fat-free mass over 10 weeks of training is about 1.5 kg. Over a five-year period, fat-free mass can increase by 12.5 to 20.2 kg, or 2.5 to 4 kg per year, depending on individual responsiveness. Highly responsive individuals could see up to a 21 kg increase, while low responders might gain only 5 kg.

What is the difference between absolute and relative muscle gain for men and women?

Women tend to gain muscle at a similar relative rate as men, meaning the percentage increase in muscle mass is similar. However, due to starting with less muscle mass, their absolute gains are lower, with estimates suggesting they may gain around 70% of the muscle mass seen in men over time.

Why is fat-free mass not the same as skeletal muscle mass?

Fat-free mass includes all lean tissue in the body, such as organs, bones, and muscle. Skeletal muscle mass is just the muscle tissue itself, which is what primarily drives fat-free mass changes, especially over the long term.

How do training experience and individual responsiveness affect muscle gains?

Individuals with more training experience tend to see smaller increases in muscle mass compared to beginners. Additionally, some people are 'high responders' to training and can gain muscle more quickly, while 'low responders' see slower progress, even with optimal training.

How does testosterone influence muscle growth, and how does it differ in natural versus exogenous use?

Testosterone plays a significant role in muscle growth, and higher doses (exogenous testosterone) lead to greater muscle increases. Natural increases in testosterone from lifting weights have less impact on hypertrophy since the changes are small compared to those seen with external supplementation.

Do acute hormonal spikes after training directly influence muscle growth?

No, acute increases in hormones like testosterone, growth hormone, and IGF-1 after exercise do not appear to significantly affect muscle protein synthesis or hypertrophic outcomes. Studies have shown that hypertrophy can occur even in the absence of large hormonal spikes.

What is mechanical tension, and why is it important for hypertrophy?

Mechanical tension refers to the force generated by muscle fibers, both active (from muscle contraction) and passive (from stretching). It is considered the primary driver of hypertrophy, with greater tension leading to more muscle fiber activation. Proximity to failure during training increases mechanical tension, though training to failure isn't always necessary.

Is metabolic stress a significant driver of hypertrophy?

While metabolic stress, resulting from the accumulation of metabolites like lactates and hydrogen ions, has been proposed to contribute to hypertrophy, it is not the primary driver. Studies suggest that training styles focused on metabolic stress do not necessarily lead to superior hypertrophy compared to other styles.

What role does cell swelling (the pump) play in muscle growth?

Cell swelling or the pump, which is a temporary increase in muscle size after training, is not a direct driver of hypertrophy. Though some enjoy the sensation of a pump, it has not been shown to cause more muscle growth compared to training styles that don't produce as significant a pump.

What does current research say about muscle damage as a cause for hypertrophy?

Research indicates that muscle damage may not play a significant role in hypertrophy. Although it was once thought to be a key factor, recent studies suggest that muscle damage alone is not enough to drive muscle growth, and the role of muscle damage in hypertrophy remains inconclusive.