Research over several decades has proven over and over again that protein is vital for anyone aiming to maximize muscularity and athletic performance. This makes sense since protein constitutes about 80% of the dry-weight of skeletal muscle and our muscle fibers require an abundant and constant supply of amino acids to support muscle repair and muscular hypertrophy (muscular growth).
Muscle protein synthesis (MPS) is the driving force behind muscle repair and muscular growth.
Muscle repair and hypertrophy can occur only if muscle protein synthesis (anabolism) exceeds muscle protein breakdown (catabolism). When muscle anabolism exceeds catabolism, you are said to be in positive muscle protein balance.
Resistance training promotes anabolism, but this is optimized only if protein and caloric intake are adequate to support positive muscle protein balance throughout recovery.
So, if you train too hard without adequate rest, calories, and/or protein intake, you will quickly fall into negative muscle protein balance and suffer muscle breakdown and muscle loss.
No fear, this is where a little science can help….
If you are new to training and struggling for lean gains or you are a pro and just want to be sure you are optimizing anabolism, read on!
In this article I’ve distilled the latest peer reviewed research to give you the most scientifically accurate and up to date recommendations to optimize protein intake for maximum muscle building and exercise performance.
- HOW MUCH DAILY PROTEIN SHOULD I BE GETTING?
As explained above, building lean muscle mass requires positive muscle protein balance. The latest research tells us that maintaining an overall daily protein intake in the range of 1.4–2.2 g protein/kg body weight/day (g/kg/d) is optimal for those seeking to maintain positive muscle protein balance and optimize muscular hypertrophy.
Higher protein intakes (2.3–3.1 g/kg/d) may be needed to maximize the retention of lean body mass in resistance-trained athletes who are dieting. Some evidence that suggests higher protein intakes (>3.0 g/kg/d) have been shown to increase fat loss in resistance-trained athletes.
- DO I NEED TO USE A PROTEIN SUPPLEMENT?
You should always aim to hit your daily protein requirements through the consumption of a variety of whole foods. While this can be difficult for those who are dieting or seeking to improve body composition, using a protein supplement is a cost effective and convenient way to ensure you ingest enough high-quality protein in the day, while minimizing caloric intake. So, if you are aiming for lean mass gains and/or fat loss a protein supplement is recommended.
- HOW MUCH PROTEIN SHOULD I HAVE WITH EACH MEAL?
Increases in training intensity and training volume increase our protein requirements. As we age, our protein requirements also increase.
General recommendations are 0.25 g of a high-quality protein per kg of body weight, per serving. If you don’t feel like doing the math, take in 20–40 g of protein per meal or snack. To maximize muscle protein synthesis , each protein dose should contain a balanced array of the essential amino acids (EAAs), with high relative levels leucine (700–3000 mg).
Higher protein doses (40-70 g) are generally needed to maximize muscle protein synthesis in aged (60+ yrs) populations.
- HOW OFTEN SHOULD I BE EATING A PROTEIN MEAL?
There’s is a substantial anabolic response after eating a protein rich meal, especially if the meal is rich in EAAs. For 1–4 h after a meal, muscle protein synthesis is elevated, resulting in positive muscle protein balance. In contrast, rates of muscle protein synthesis are lower in a fasted state, since muscle protein balance is negative.
Although total daily caloric and protein intake over the long term play the most crucial dietary roles in optimizing recovery and supporting muscular development. Ideally, protein dosing should be evenly distributed, every 3–4 h, across the day.
Spreading these feeding periods out by approximately 3-hours has been consistently reported to promote sustained and increased levels of muscle protein synthesis and performance benefits.
- PRE-WORKOUT OR POST-WORKOUT PROTEIN?
Total daily caloric intake and adequate protein ingestion over the long term play the most significant roles in optimizing exercise recovery and supporting muscular development. But, once these factors are accounted for, pre- or post-workout protein intake optimizes physical performance by fully supporting recovery processes.
Around the workout window (known as the peri-workout period), the optimal time period to ingest protein is a matter of individual choice, since benefits are gained from pre- or post-workout ingestion.
The post-workout “anabolic window” was once believed to be only 2-4 hours long. Research in the past few years tells us that the post-workout anabolic response is much longer-lasting than we once thought (at least 24 h), but it does decrease with time after training.
Protein ingestion synergizes with each exercise session to stimulate increased muscle protein synthesis. Around the workout window, the greatest anabolic response is noted when high EAA protein consumption occurs within a window of 30-120 minutes before or after resistance exercise.
- WHAT TYPE OF PROTEIN IS BEST FOR MUSCLE BUILDING?
Animal proteins (meats, eggs, fish, and dairy) tend to be the best choices for muscle gain and athletic performance due to their high essential amino acid (EAA) content and high relative levels of leucine.
In terms of protein supplementation, whey protein provides the purest and most bioavailable source of EAAs. Rapidly digested proteins, like whey, that contain a high proportion and a full array of EAAs (with adequate leucine) are most effective in supporting recovery and stimulating muscular growth. Thus, using whey protein isolate or concentrate in the peri-workout period is your best choice.
If you are a vegan athlete or you cannot tolerate milk proteins, look for a high quality vegan protein supplement that has an abundance of EAAs, with a high relative amount of BCAAs (leucine, Isoleucine, and valine).
How do I protect my muscular gains while I sleep?
While we sleep we undergo a significant fasting period, which can lead to negative muscle protein balance throughout the night. Slower digesting proteins, taken right before bed, are an excellent strategy to circumvent overnight catabolism.
Casein is the most abundant protein found in cow’s milk. Micellar casein has the unique ability to form a gel in the stomach, slowing absorption, and making it a sustained supplier of amino acids. Pre-sleep micellar casein supplementation (30–40 g) is scientifically proven to provide a sustained release of amino acids into the blood stream, which promotes increased muscle protein synthesis, for up to 7 hours, while you sleep. If you are looking for natural food sources of casein, the best ones are cottage cheese and Greek yogurt.
What about protein blends?
Protein powder blends are formulated using proteins from many sources with different absorption profiles. The rationale for such products is to deliver a single protein supplement that provides all the unique advantages of fast, medium, and slow digesting protein sources.
- With an array of proteins with differing absorption rates, protein blends are ideal for someone who wants a “well-rounded” protein supplement for anytime of the day.
- Protein blends are great for people on a budget or just starting out, as they save buying multiple protein supplements for different times of the day.
- With a broad spectrum of absorption and robust amino acid profiles, protein blends are an ideal protein boost for those who don’t have the opportunity to take time out to eat every 2-3 hours.
If you are looking for a protein blend, the best products contain fast digesting whey protein hydrolysates and isolates, as well as slower digesting milk protein isolates and/or micellar casein.
Dr. Dwayne N. Jackson, is an active Medical School Professor and Medical Scientist in the Department of Medical Biophysics at Western University in Canada. He is a world leader in the areas of medical physiology, exercise physiology, health, nutrition, and supplementation. Dr. Jackson’s innovations in research and education have led to numerous scientific awards, teaching awards, peer-reviewed scientific articles, and important advances in medicine and human health.
If you want to know more about optimizing your health through real science, check out www.yourvitalscience.com and follow Dr. Jackson on Instagram: @drdnjackson
Tipton KD, Wolfe RR. Exercise, protein metabolism, and muscle growth. Int J Sport Nutr Exerc Metab. 2001 Mar;11(1):109-32. doi: 10.1123/ijsnem.11.1.109. PMID: 11255140.
Jager R, Kerksick CM, Campbell BI, Cribb PJ, Wells SD, Skwiat TM, et al. International society of sports nutrition position stand: protein and exercise. J Int Soc Sports Nutr. (2017) 14:20. 10.1186/s12970-017-0177-8.
Andersen LL, Tufekovic G, Zebis MK, Crameri RM, Verlaan G, Kjaer M, et al. The effect of resistance training combined with timed ingestion of protein on muscle fiber size and muscle strength. Metab Clin Exp. 2005;54:151–6.
Thalacker-Mercer A, Riddle E, Barre L. Protein and amino acids for skeletal muscle health in aging. Adv Food Nutr Res. 2020;91:29-64. doi: 10.1016/bs.afnr.2019.08.002. Epub 2019 Oct 22. PMID: 32035599.
Joanisse S, Lim C, McKendry J, Mcleod JC, Stokes T, Phillips SM. Recent advances in understanding resistance exercise training-induced skeletal muscle hypertrophy in humans. F1000Res. 2020 Feb 24;9:F1000 Faculty Rev-141. doi: 10.12688/f1000research.21588.1. PMID: 32148775; PMCID: PMC7043134.
Yoshida T, Delafontaine P. Mechanisms of IGF-1-Mediated Regulation of Skeletal Muscle Hypertrophy and Atrophy. Cells. 2020 Aug 26;9(9):1970. doi: 10.3390/cells9091970. PMID: 32858949; PMCID: PMC7564605.