Welcome to factsaboutfitness.com.
Welcome to factsaboutfitness.com.
There is a lot of talk about the amount of protein one should eat per day. The truth is, there is not just one number that is right for everyone. The amount of protein you should eat depends on many factors such as age, activity level and pre-existing medical conditions. The current RDA recommendations for a healthy adult is a minimum of .8g/kg/day to avoid net nitrogen losses (Phillips, Chevalier & Leidy, 2016). However, according to Ko, Obi, Tortorici & Kalantar-Zadeh (2017) for those with kidney disease a lower number is recommended at 0.6–0.8 g/kg/day. For informational purposes on this topic of protein, we will use the .8g/kg/day for an adult without kidney disease. For those who are exercising for health or competition, more than .8g/kg/day is necessary for muscle protein synthesis and a positive protein balance for muscle development. Protein should be consumed every 3-4 hours throughout the day distributed evenly between meals. (Stark, Lukaszuk, Prawitz & Salacinski, 2012).
The formula for converting lbs to kg is: weight in lbs divided by 2.205.
Example: 190lb/2.205= 86kg
For the Exercising adult and athlete: Athletes increase protein intake to optimize adaptations to their training and achieve maximum results for competition. In order for an athlete to achieve their goals, they want an optimally functioning musculoskeletal system, cardiovascular system, immune system and overall optimal physiological function. Protein ideally should come from whole foods containing all essential amino acids at a dose of 1.2-2.0g/kg/day (Phillips, Chevalier & Leidy, 2016).
For example:
a 190 lb exercising adult = 86kg
86kg x 1.2g = 103g of protein per day
4 meals per day would be ~26g per meal
On the higher end for Athletes trying to build muscle:
A 190 lb Athlete = 86kg
86kg x 2.0g = 172g of protein per day
4 meals per day would be ~43g/ meal
5 meals per day would be ~34 g/meal
For the older population: As the body ages, protein synthesis is impaired which causes sarcopenia. Sarcopenia is the gradual reduction in skeletal muscle size and function. The exact cellular mechanisms that cause it are not fully understood. However, there is ample research to indicate metabolic impairments are present in the skeletal muscle of older adults. Impairments in protein synthesis to anabolic stimuli that happen over time, are likely to contribute to the loss of muscle size and function (Dickinson, Volpi & Rasmussen, 2013).
However, strategic pairing of exercise and nutrition is a practical strategy that has promise for restoring and preserving skeletal muscle size and function in older adults. Eating an appropriate amount of protein throughout the day and performing routine exercise may preserve the protein synthesis response of skeletal muscle, slow the progression of muscle atrophy and increase the ability to build muscle. For the young and older adult, a post exercise meal containing 20g of protein is suggested to stimulate protein synthesis. However, recent data indicate that relative to younger individuals, older adults may require a larger quantity of protein/amino acids following resistance exercise to maximally stimulate skeletal muscle protein synthesis. Therefore, a post exercise consumption of 25-30g may be necessary for the older adult (Dickinson, Volpi & Rasmussen, 2013).
* If you currently use or are considering the use of a protein supplement, use these links to find quality, safe products that are certified to contain exactly what is on the label with no chemicals or byproducts.
https://www.cleanlabelproject.org/protein-powder/
References
Dickinson, J. M., Volpi, E., & Rasmussen, B. B. (2013). Exercise and nutrition to target protein synthesis impairments in aging skeletal muscle. Exercise and sport sciences reviews, 41(4), 216–223. doi:10.1097/JES.0b013e3182a4e699
Phillips, S. M., Chevalier, S., & Leidy, H. J. (2016). Protein “requirements” beyond the RDA: implications for optimizing health. Applied Physiology, Nutrition & Metabolism, 41(5), 565–572
Stark, M., Lukaszuk, J., Prawitz, A., & Salacinski, A. (2012). Protein timing and its effects on muscular hypertrophy and strength in individuals engaged in weight-training.Journal of the International Society of Sports Nutrition, 9(1), 54. doi:10.1186/1550-2783-9-54