Three health benefits and functions of L-leucine



People who work out generally know that protein in the diet is important for muscle building, strength performance, body recovery and overall health, but besides protein, have you consumed enough L-leucine? So, what is leucine? What's in it for you? We'll tell you the answer below.


What is L-leucine?

Leucine is one of the 9 essential amino acids and one of the 3 branched chain amino acids, so it cannot be produced in our body and must be obtained through dietary sources. Once ingested, leucine is primarily used in skeletal muscles, which caught the attention of researchers who have since begun studying leucine's potential properties. Recommended dietary intake of leucine: 14 mg/kg body weight ~ >45 mg/ kg body weight (for active people), it is very important to get enough leucine. 

1. Helps improve body composition

gain muscle

Leucine stimulates signaling pathways that lead to the synthesis of new muscle proteins. Increased muscle protein synthesis puts the body in a state of positive nitrogen balance – which is what you want if you are building muscle mass.

In a review that analyzed nearly a thousand participants, the performance-enhancing (ergonomic) effects of leucine were studied. Leucine supplementation has been reported to increase lean muscle mass and total body weight compared to those who do not take leucine.

In one particular study, participants who took 3 grams of leucine twice daily gained an average of 1.9 kilograms of lean muscle mass through a 12-week resistance training program. These are mainly Type II (fast-twitch) muscle fibers that benefit from leucine. Type II fibers are mainly responsible for strength and explosive movements (such as sprinting).

What's more, the increased muscle response after leucine supplementation alone was comparable to the muscle gains seen with complete proteins such as whey protein concentrate, whey protein hydrolyzate, and soy protein concentrate. Another bonus, leucine has fewer calories per serving than whey protein, so if you're trying to control your caloric intake, leucine is a great choice.



Prevent muscle breakdown

Most of us don't train 365 days a year. Taking a break from training is natural and necessary – whether due to injury, illness, or simply to give your body a rest. During these recovery periods, we want to avoid losing the muscle that we worked so hard to build. Fortunately, leucine can help.

You lose muscle mass when you are in a negative nitrogen balance - this is when the muscle-breaking force is greater than the muscle-building capacity. Studies show that leucine can prevent muscle breakdown. We're not sure yet how leucine helps us maintain muscle mass - scientists are still studying this.

Muscle failure is common during prolonged periods of muscle inactivity or immobility, such as bed rest. Researchers highlight that leucine is key to preventing muscle loss.

As we age, we are more likely to exercise less and lose muscle. One research team conducted an experiment on middle-aged adults. During a week of bed rest, consuming 13 grams of leucine per day not only reduced the loss of lean muscle, but also reduced the loss of lean muscle. It also prevents the increase of body fat.

Therefore, taking leucine after exercise or adding more leucine-rich foods to your diet (meat, fish, and eggs are good choices) can help us maximize muscle growth while working out in the gym, or when not exercising. to prevent muscle loss.


2. Improve sports performance


You may have never held a dumbbell before, or you may struggle with your workouts, but leucine can help take your strength performance to the next level. As we said before, leucine stimulates muscle growth, and generally speaking, muscle gain equals strength gain.

In the experiment, a group of untrained men participated in a 12-week resistance training program. Half of them took 4 grams of leucine per day, and the other half took nothing (the placebo control group). In eight sets of workouts, the maximum weight they could perform for five repetitions was recorded. After 12 weeks, both groups' performance improved, while the leucine group's strength increased significantly - increasing from the start of training. 41%, while the placebo group increased intensity by 31%.



During strenuous endurance exercise (for example, a marathon or a tennis match), blood levels of leucine decrease significantly, indicating increased demand and uptake by skeletal muscle. This seems to imply that endurance performance may be enhanced by supplementing an increase in blood leucine levels.

In a randomized, double-blind study of canoeists, one group took daily leucine supplements for 6 weeks, resulting in increased high-intensity rowing time to exhaustion. Kayakers also report that the sport feels easier when taking leucine.

Strength, speed or endurance - no matter what style of exercise you take, leucine can help you improve your performance.




3. Improve immunity

Leucine can play a beneficial role in the immune system. During an immune response, our bodies activate T cells, which help fight harmful bacteria and microorganisms. Activation requires the same mTOR signaling pathway as before, but this time used to regulate T cell function - essentially ensuring they are ready for bacterial invasion.

What is the biggest helper to activate mTOR again? ——Leucine So supplementing with leucine can boost your immune system and reduce your risk of illness. If you’re typically prone to colds and feeling unwell throughout the winter months, now is the perfect time to add leucine to your healthy living and fitness regimen.

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