Dietary protein provides amino acids, which are components of muscle. The specific muscles that ingested protein progresses are:
- Contractile – cause muscle contractionsby converting chemical energy to mechanical work.
- Structural proteins – provide support for muscles to move bone levers and therefore limbs.
- Regulatory enzymes – to speed up reactions, specifically metabolism of dietary macronutrients to convert them to energy accessible for the body.
As you can see from their functions, strengthening and building these muscles will improve performance.
To maintain muscle mass, its breakdown and synthesis must be balanced.
To gain muscle, its synthesis must be larger than its breakdown – resulting in a positive protein balance.
Different muscle masses are gained in different proportions depending on the type of training that is done:
- Endurance training –
- Gains mitochondrial mass– increases mitochondria which converts unusable energy to useable energy when oxygen is present.
- Resistance training –
- Gains myofibrillar mass– enhances strength and lean body mass.
Both of these types of training increase protein synthesis AND breakdown after exercise; however, to make muscle, amino acids must be present. Without a large pool of amino acids, muscle breakdown occurs without synthesis. Amino acids are ingested from dietary proteins.
Breen, L., Philip, A., Witard, O.C, et al. (2012) ‘The influence of carbohydrate-protein co-ingestion following endurance exercise on myofibrillar and mitochondrial protein synthesis’, J Physiology, 589, pp. 4011-4025.
Carraro, F., Stuart, C.A., Hartl, W.H., Rosenblatt, J., and Wolfe, R.R. (1990) ‘Effect of exercise and recovery on muscle protein synthesis in human subjects’, Am J Physiology, 259, pp. 470-476.