Discussion
skeletal muscle hypertrophy, muscle hypertrophy
In the current study, we demonstrate that a high-protein (1.8 g·kg bmDietary protein intake and resistance exercise are the key drivers of skeletal muscle hypertrophy, achieved physiologically by additively stimulating MyoPS rates and thereby facilitating periods of positive net protein balance [Literature surrounding protein requirements to support resistance training-induced muscle hypertrophy has largely been deduced from studies where participants have consumed omnivorous diets with an emphasis on the intake of (generally supplemental) high-quality animal-derived proteins [The apparent contrast between our data and previous narratives of non–animal-derived dietary proteins being inferior to support MyoPS rates and associated adaptive responses may be explained in several ways. Previous studies have generally investigated a minimal number of (lower quality) supplemental (that is, refined/isolated) plant-based proteins for their capacity to stimulate hourly (post-exercise) MyoPS rates [Another key consideration for why our 2 dietary groups achieved comparable responses to training concerns the high(er) protein diets selected. We deliberately selected an “optimal” training and dietary approach to maximize MyoPS rates and training adaptations within our control group, and therefore to reveal any potential decrements in the vegan diet. As a result, we cannot extrapolate the present work to low(er) protein diets more in line with current RDAs; although based on the hourly post-exercise MPS response to bolus mycoprotein ingestion [During Phase 2 of the study, significant muscle hypertrophy occurred alongside considerable increases in strength (23% on average across exercises), the magnitude of which is in line with previous comparable studies [There are some ancillary considerations of our data that we would be remiss not to discuss. The current study applied a holistic dietary intervention as opposed to protein supplementation (alone), meaning aspects beyond protein To conclude, we showed that a high protein, mycoprotein-rich vegan diet can support comparable daily free-living MyoPS rates as an isonitrogenous omnivorous diet in resistance training young men and women. These metabolic data translated to (and likely explain) the omnivorous and (virtually exclusive) vegan diets facilitating comparable increases in muscle fiber size, muscle volume, whole body lean mass, and muscle strength throughout 10 wk of high-volume resistance training. As such, a carefully designed vegan diet is capable of supporting optimal skeletal muscle adaptive responses to resistance training.