Rosie Chee talks muscle growth and why the right macronutrient profile is essential for building optimal mass.
To gain muscle mass one must be in a POSITIVE energy balance, with a recommendation of ~15% energy increase from maintenance, to ensure that the weight gain acquired from the resistance training undertaken results in muscle accretion .
Glycogen is the primary fuel utilized during anaerobic, high intensity training ; therefore adequate carbohydrate intake is necessary to provide energy for resistance training .
Muscle damage occurring as a result of resistance training increases the daily carbohydrate intake for optimal muscle glycogen synthesis .
According to studies done, 5-6g/kg/day of carbohydrate are required for optimal muscle glycogen levels in those looking to gain muscle [1,4].
It is recommended that carbohydrates make up 55-60% of daily total energy intake .
The body’s nitrogen balance is improved as a result of resistance training; therefore resistance training increases the daily protein intake requirement  through the additional need for amino acids to support muscle accretion . Adequate protein must be available for amino acids to provide protein synthesis (i.e. muscle growth), since muscle is primarily protein and water . There is a level of g/day at which dietary protein becomes optimal for muscle growth; however, above this there are no further anabolic effects, with excess protein ingested being oxidized through other metabolic pathways [1,6,7].
The use of anabolic compounds protein requirements has been shown to DECREASE the protein required for positive nitrogen balance , most likely due to an increase in the reutilization of amino acids from the protein degradation for protein synthesis as a consequence of anabolic administration .
According to studies done  the general population require only 0.8g/kg/day of protein. Bodybuilders and those trying to gain muscle mass require higher amounts, ranging from 1.0-1.2g/kg/day for those who do their resistance training in a steady-state, and as much as 1.5-1.7 g/kg/day for those who train in the early morning or in a fasted state [5,6,7,10,11,12].
It is recommended that protein make up 25-30% of daily total energy intake .
There is little known on how fat intake affects muscle accretion . There is however evidence to suggest that a high daily fat intake impairs high intensity exercise performance . Yet low dietary intakes of fat are not optimal for muscle growth, as they have been shown to decrease total testosterone .
It is recommended that fat make up 15-20% of daily total energy intake .
To achieve muscle accretion one must have a positive energy balance (~15% above maintenance), a moderate to high carbohydrate intake (55-50% total daily energy) to fuel resistance sessions, optimal protein intake (25-30% total daily energy) to ensure protein synthesis, and an adequate fat intake (15-20% total daily energy) to prevent testosterone levels falling.
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