The importance of proper nutrition for health is something that most of us have already internalized. We are increasingly concerned about “eating better”, consuming local food and, if possible, from sustainable production. In addition, the growing awareness of animal welfare has led us to eat more plant-based food.
Within this trend, the preference for choosing meat substitutes stands out, which favors a greater consumption of plant-based protein. Likewise, food companies have been developing products that are increasingly similar to meat, improving both organoleptic and nutritional characteristics.
But we are also aware that leading an active lifestyle is essential to staying healthy. Thus, the growing interest in sports where there is a gain in strength and muscle mass, such as bodybuilding, weightlifting, powerlifting or crossfit, stands out.
For this reason, the proteins we eat have become increasingly important, given the role they play in said gains in muscle mass and strength. And in this scenario, those of animal origin are considered top than those of plant origin.
Virtues of protein of animal origin
To achieve an increase in muscle mass (hypertrophy) it is necessary to stimulate protein synthesis in the muscle. The two main stimuli are resistance exercise and dietary protein. But the former also increases protein catabolism (the breakdown of proteins) in muscle. Therefore, a nutritional intake that guarantees a positive protein balance (that synthesis is greater than degradation) is essential to achieve muscle hypertrophy.
In theory, animal protein is considered better for muscle mass and strength gains due to its greater ability to stimulate muscle protein synthesis (anabolic capacity). This is mainly attributed to its superior quality, determined both by the profile of essential amino acids and their bioavailability (proportion of amino acids absorbed and used by the body).
Although all dietary amino acids are necessary to synthesize new proteins, the only ones that stimulate muscle synthesis are the essential ones; especially leucine.
Generally, the protein of plant origin has lower concentrations of essential amino acids than that of animal origin. In most cases, one or more of them do not meet the needs, such as methionine in legumes and lysine in cereals.
On the other hand, the amino acids of the vegetable protein are digested and absorbed to a lesser extent than those of the animal. Therefore, both the initial dietary intake and the amount of amino acids used by the body will be lower.
Consequently, plant-based protein is considered less suitable than animal-based protein for generating muscle adaptations.
Other factors to consider
But in addition to the amino acid profile and bioavailability of dietary protein, there are other factors involved in muscle protein synthesis. Regardless of its quality, the quantity that is ingested must be sufficient to generate a positive balance.
To do this, it is recommended to consume between 1.6 and 2 grams of protein per kilo of weight daily. In the case of vegetable origin, as it has a lower concentration of total essential amino acids, quantities close to the upper limit of the range are recommended: 2 g/kg/day.
If body fat loss occurs, higher amounts of dietary protein are recommended for both vegan and omnivorous athletes. The goal is to maintain lean mass.
Furthermore, the daily distribution of protein intake also matters. If the objective is to maximize its synthesis in the muscle, it is recommended to take it evenly throughout the day, in doses of 20-40 g. In this way it is possible to generate multiple anabolic peaks.
Another essential nutritional factor to increase muscle mass is energy intake. Being an anabolic process, the energy balance must be positive; that is, your intake must be greater than your expenditure.
And what do the studies say?
The studies carried out to date suggest that, in practice, the origin of the protein does not imply any advantage or disadvantage in the gain of muscle mass or strength, regardless of its anabolic capacity, as long as the amounts ingested are sufficient.
In this sense, no significant differences were observed in terms of muscle strength gain in individuals who performed routines that work all muscle groups in the same session who took protein of animal or vegetable origin. Similar results have been described regarding its influence on muscle hypertrophy. However, most of this research has looked at the effect of protein origin when it is consumed as a supplement.
In conclusion, the available evidence suggests that, despite what might be expected, the origin of the protein does not seem to be a determining factor in terms of gains in strength and/or muscle mass. However, additional studies are needed to look at the effects of consuming it through the diet, rather than in supplement form.