Quick Answer:
During a workout, your muscles are getting small tears on the cellular level that, when healed, result in muscle growth. The repair is done via protein synthesis. The damaged muscle fibers are repaired with new muscle protein that is thicker and able to handle stress better than its predecessor.
Full Answer:
During a workout, your muscles are getting small tears on the cellular level that, when healed, result in muscle growth. The repair is done via protein synthesis. The damaged muscle fibers are repaired with new muscle protein that is thicker and able to handle stress better than its predecessor.
To achieve muscle growth the muscle must experience a number of events. First, you will have to exercise and put your muscles under tension to develop small micro-tears in the fiber; Metabolic stress that alerts your body that your muscle needs rebuilt; and a proper diet to give the body the amino acids that it needs for protein synthesis to occur.
Protein for muscle repair is made from amino acids that your body collects from a high protein diet. If you are not consuming all the essential proteins, your body will not be able to rebuild the muscle that has been damaged.
For optimal performance, the best time to consume protein post workout to increase muscle growth is within the first 30 mins – 1 hour. If you miss this time period however anytime within the first 24 to 48 hour window will help the damaged muscle.
There are a few ways to measure protein synthesis:
Nitrogen Balance:
The macros, carbs and fats are made of carbon, hydrogen, and oxygen. Protein on the other hand contains an additional nitrogen element. To find the amount of protein synthesis that occurs you would measure the amount of nitrogen intake – the nitrogen excretion. If your number is positive, you are gaining protein and it is assumed that you are growing muscle.
Tracers:
Typically done with amino acids, tracers are an amino acid with an additional neutron making it weigh more and differentiate them from the regular amino acids. The tracers are followed through the body to watch the protein synthesis occur.
Whole Body Protein Metabolism:
Whole body protein synthesis is not the same as muscle protein synthesis; it refers to any protein in the body. This is similar to the nitrogen balance shown above except in measures more than anabolic or catabolic state. In addition, this method shows whether the changes are due to protein synthesis, protein breakdown, or both.
References: Muscleandstrength, Muscleandfitness, Livestrong, Builtlean, Nutritiontactics