I’ve heard all sorts of arguments about training being more important than nutrition, and visa versa. Some people say muscle growth is all about the training, while others says it’s 80% nutrition and just 20% training.
Just the other day I read an article on a website that said training is WAY more important than nutrition when it comes to building muscle. The person who wrote the article made the argument that he observed a group of guys with “the worst diet ever”, but who are muscular and strong.
This was his proof that training beats nutrition in the muscle growth department.
The article went on to say that if you had the worst possible diet for building muscle, consisting of junk food and no protein, you will gain muscle from a weight training program alone.
Wait, let me get this right… junk food and no protein combined with weight training will build muscle?
I almost fell off my chair when I read that, because it’s wrong beyond belief.
He didn’t go into detail about what these men were eating, but if their diets were poor and they managed to build some muscle with training then they were obviously consuming enough calories and had a sufficient amount of protein.
It’s physiologically impossible to build muscle tissue without sufficient nutrients, period!
How do I know this?
Because there are many well conducted scientific studies out there to prove it, which I will cover in more detail shortly.
To find out the facts about how training and nutrition affect muscle growth, and which has the biggest impact, we’re going to look at three things.
- How training alone affects muscle growth
- How training and nutrition combined affects muscle growth
- How nutrition alone affects muscle growth
Fortunately, Stuart M. Phillips, PhD at the Exercise Metabolism Research Group, Department of Kinesiology, McMaster University, conducted an in depth study  looking at these very three factors.
Let’s take a closer look at each of the findings.
Training and Muscle Growth
When you lift weights, two key things happen in your muscles.
1) There is an increase in protein synthesis
2) There is an increase in protein breakdown
What does this mean?
Your muscles are in a constant state of synthesising and breaking down muscle tissue in a process called protein turnover. The only way muscle growth can happen is if synthesis exceeds breakdown. In other words, you need to be building (synthesising) more muscle than you’re breaking down.
Take a look at the graph below from PhD Stuart M. Phillips study to see what happens in your muscles during/after intense weight training.
The red box labelled ‘RE’ represents ‘Resistance Exercise’. This shows you what happens to your muscles from resistance exercise alone, without food.
The white bar shows the level of protein synthesis in response to weight training. It’s elevated, exactly what you want for muscle growth to occur. But look at the grey bar, this indicates muscle protein breakdown. As you can see, breakdown exceeds synthesis so there is a negative protein balance. In other words, more muscle is being lost than built.
That’s right; weight training causes a breakdown, or loss of muscle tissue. The only way to stop this muscle loss and to build muscle with a weight training program is to add sufficient nutrients, which takes us to the next section.
Training and Nutrition on Muscle Growth
Take a look at the graph again but this time at the last column. What you see here is the effects of RE (resistance exercise) combined with AA (amino acids). In case you didn’t know, protein is made of amino acids, and it’s these amino acids from high protein foods that build muscle – think whey, eggs, chicken, fish and beef – all high protein foods rich in muscle building amino acids.
Now, check out the last column and see how combining resistance exercise with amino acid (protein) feeding impacts muscle growth. As you can see, the white bar representing protein synthesis has dramatically increased, and the grey bar, representing protein breakdown has dropped. This is called a positive protein balance, and puts you right in the muscle building zone.
You see, the only way to build substantial muscle is with both proper training AND nutrition. Training and nutrition work synergistically to increase lean muscle mass, more importance should not be placed on one over the other. For optimal muscle hypertrophy, both should get equal attention.
Now we’ve looked at the difference between resistance weight training with, and without food. It’s perfectly clear that it’s not possible to build muscle without sufficient nutrients.
The author of the article I talked about at the beginning of this post was incorrect in his belief that training alone is enough to build muscle. In fact, we now know that training without nutrition actually leads to muscle loss!
The group of men that he described as building strong muscular physiques while eating “the worst diet ever” must have been consuming enough protein to promote growth, it’s that simple. However, if they continue eating a poor diet, with limited protein and not paying attention to their nutrition you can be assured that their results will come to a grinding halt. They will reach a point where progress slows and stops, unless they increase their protein and calorie intake.
In the next section I will finish by looking at the impact food alone has on muscle protein synthesis and growth.
How Nutrition Alone Affects Muscle Growth
Now here’s the proof that nutrition has the upper hand over training on muscle growth. Look at column two on the graph below. It shows us what happens when we eat protein rich foods while at rest. The column represents Rest + AA (amino acids / protein).
Notice anything interesting about the results?
Protein synthesis exceeds breakdown resulting in a positive protein balance, and shows that eating protein alone WITHOUT any exercise increases muscle protein synthesis and reduces muscle protein breakdown.
Just eating protein alone is enough to stimulate protein synthesis and increase muscle size. Obviously you’re not going to build a massively muscled physique by just eating, there is a limit to the stimulation of protein synthesis, but it’s proof that the power of food alone can build muscle, and that nutrition should never be neglected.
If you think about it, when malnourished prisoners of war were rescued they weren’t sent to the gym to get their body weight back up (lean muscle mass). Of course not, they were fed nutritious foods and that was enough to reinstate their muscle size to a healthy weight again.
Another study conducted by the Pennington Biomedical Research Centre, Louisiana State University , looked at how overeating affects body composition.
The study had a group of 25 young adults live in the university’s metabolic unit for a whole three months. The study researchers worked with the group for 25 days until they found each of their daily calorie requirements to maintain their current body weight.
Once each person in the group was eating just the right amount of calories to maintain their weight, the researchers then added an additional 954 calories to their daily diet. Every person in the group was closely monitored to assure that every extra calorie was consumed.
The participants were split into three groups.
Group 1: Low protein diet (5% of calories from protein)
Group 2: Normal protein diet (15% of calories from protein)
Group 3: High protein diet (25% of calories from protein)
Each group ate the same amount of carbohydrates at around 41% of daily calories. The group of participants lived a sedentary lifestyle (no exercise) throughout the study.
After 8 weeks of eating almost 1000 extra calories each group gained weight, no surprise there. But here’s where it gets interesting. The low protein diet group lost 1.5 pounds of lean body mass (muscle) with the weight increase consisting entirely of fat, not good if you want an attractive physique.
The normal and high protein groups gained 13 – 14 pounds of weight, but this weight increase consisted of both fat and muscle mass.
Yet more scientific proof that eating alone without any exercise can build muscles.
Muscle tissue doesn’t magically grow out of thin air – food is an essential requirement. You must apply equal attention to training and nutrition to maximize growth.
Both of the studies above have shown that the act of eating alone can cause muscle gain. The first study proves that training alone on a diet void of protein can’t build muscle. That doesn’t mean you should focus most of your attention on diet, you need to pay equal attention to both or you’ll miss out on muscle gains.
The more you can be in a positive protein balance, the more muscle you will gain. Conversely, the more you’re in a negative protein balance, the more muscle you will lose. To stay in a positive protein balance you need to follow a solid training + nutrition program.