When it comes to getting stacked there’s never going to be a substitute for hard work in the weights room. However, optimizing muscle growth depends on diet and, more specifically, protein intake. Unfortunately, recommendations are often confusing: take 15–35% of total calories or a certain amount of protein per day based upon bodyweight, for example.

Knowing how much to eat isn’t enough to optimize your gains, here’s how to tap into an often overlooked aspect of your protein intake: the when.



Fine tuning your leucine

Working out the optimal amount of protein per meal is far better than using daily protein recommendations. So exactly how much protein per meal and how much time between meals is the absolute best?

Well, the answer entirely depends on one very special amino acid: leucine. It’s one of the three branched-chain amino acids (along with isoleucine and valine) and research shows it’s the ringmaster for protein synthesis in your muscles following a meal. Without it, the other 19 amino acids cannot kick-start your muscle growth into hyper-drive. In fact, leucine can stimulate muscle growth by itself almost just as well as it can when combined with all other 19 amino acids.

When leucine is supplemented alone, protein synthesis lasts about two hours, but when leucine is chowed down with a complete meal that includes protein, carbohydrates and fats, the duration is prolonged to approximately three hours. In order to maximize long-term growth, your diet needs to be designed to consistently maximize your protein synthesis. Proper protein timing will keep you in a positive balance when protein synthesis is weighed against protein breakdown.


Be aware of capacity

There is no true storage capacity in the body for protein like there is for carbohydrate (glycogen) and fat (triglycerides), and after eating the optimal amount of leucine, protein synthesis plateaus. So, in regards to muscle growth, gorging on any more leucine beyond a point is an exercise in futility, technically called leucine saturation.

Once you reach this point, the muscles get a little less receptive to additional leucine for up to four hours. It’s like filling up a bucket that has a tiny hole in the bottom of it – you have to wait for water to drain out before you can refill it.


Get some for yourself

Leucine is found at highest amounts in complete, high-quality protein sources including meats, eggs, milk and whey and casein protein supplements. For starters, these protein sources should be staples in any athlete’s diet, but timing will maximize your chance at growing those bigger biceps you’ve been working on.

Research has shown that 3–4g leucine maximizes muscle protein synthesis (at the most 0.022 times bodyweight (lb)). Sadly, nutrition labels don’t provide the amount of leucine, but 20–40g of the proteins listed previously will deliver the optimal amount of leucine. Simply put, eat 20–40g of one of these protein sources with a meal frequency of every three to four hours to provide the best stimulus for muscle growth throughout your day.

And there’s solid science to back this up. A recent study in The Journal of Physiology investigated the effects of timing and distribution of whey protein by providing participants with either eight 10g doses every 1.5 hours, four 20g doses every three hours or two 40g doses every six hours. Research revealed that 20g whey protein consumed every three hours was superior for stimulating protein synthesis throughout the day. Take-home message? Regularly snacking on 20–40g of high quality protein every three to four hours maximizes your chances of adding muscle and performing better.


Key time points:

Pre and post-workout: keep your muscle primed for recovery by having 3–4g leucine before and after hitting the gym.

Before bed: getting eight hours of sleep can be vital for muscle recovery, but it also means you have to wait until morning to spark protein synthesis again.

Blunt your overnight protein breakdown by enjoying a protein-rich midnight snack. A combination of fast and slow-digesting protein will maximize muscle growth while you sleep. Try a scoop of whey protein mixed with Greek yogurt.


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