Both lower and higher carbohydrate diets gained muscle mass equally. Strength gains were similar between lower and higher carbohydrate diets.
DO CARBS HELP BUILD MUSCLE SUMMARY
- Many bodybuilder have questioned, “Do Carbs Help You Build Muscle?” A new study found that both lower and higher carbohydrate diets gained muscle mass equally. Furthermore, Strength gains were similar between lower and higher carbohydrate diets.
ARE CARBS GOOD FOR BUILDING MUSCLE?
There has been debate in the fitness and keto bodybuilding community as to how important carbs are for building muscle. Most large-scale review articles suggest that low-carb/ keto diets may be better for fat loss but are generally less effective for gaining muscle, improving performance, and enhancing strength. (Ashtary-Larky et al., 2022; Koerich et al., 2022) Previous research has suggested that complex carbs may increase muscle gains by increasing muscle glycogen which may increase anabolic activity in muscle. (Creer et al., 2005)
An important caveat is that many studies did not match calories, so the keto diet group ate fewer calories and thus were in a greater calorie deficit. Being in a calorie deficit is not conducive to building muscle. (Aragon & Schoenfeld, 2020)
The decreases in appetite have been attributed to the high protein intake (i.e., amino acids) consumed on ketogenic diets and increased appetite-suppressing hormones (i.e., decreased leptin, ghrelin, etc.), resulting in a lower caloric intake. Others have suggested that the increased fiber from consuming more vegetables while following a ketogenic diet also contributes to reduced caloric intake.
CAN YOU BUILD MUSCLE ON KETO?
Ketogenic diets have a large following, and many people get quite angry if you tell them a ketogenic diet results in lean muscle loss. The research does point to the fact that if calories are similar, you can gain muscle on a low-carb diet. (Brinkworth et al., 2009; Wilson et al., 2020)
In a review of the research that assessed 5 studies with 101 participants. When the calories and protein are similar, there was no difference in gains in lean muscle mass when following a keto diet compared to a high carbohydrate diet. (Vargas-Molina et al., 2022)
LOW-CARB DIETS DON’T AFFECT STRENGTH TRAINING
Not consuming carbs has been suggested to cause a reduction in training intensity, leading to a reduction in glycogen stores and a decrease in muscle growth. (Note: A recent study found that keto diets do not impair workout performance when performing less than 10 sets per muscle group. (Henselmans et al., 2022)
DO CARBS HELP BUILD MUSCLE
Based on previous research, carbohydrate consumption for optimal performance during resistance exercises ranges from 3-7 g/kg/day or 1.3 to 3.18 pounds per day. (Slater & Phillips, 2011) Researchers took resistance-trained men and broke their diets into a low-carb group (< 5.0 g/kg/day or <2.2 grams per pound per day) or a higher carbohydrate intake (>5 g/kg/bw or >2.2 pounds per day). The goal was to analyze their diets based on those using lower and higher-carb diets.
The subjects trained for 8 weeks. Muscle mass, fat mass, and strength gains were assessed before and after the study. To be clear, this was not a keto diet, but rather lower and higher carbs.
The higher carb group consumed about 380 grams daily, whereas the low carbohydrate group consumed about 281 grams daily. The higher carbohydrate group ended up consuming more calories, more protein, and more fat. So to be fair, these diets were not calorie matched.
HOW MANY GRAMS OF CARBS PER DAY TO BUILD MUSCLE?
At the end of the study, there were no differences in strength gains between the lower and higher carbohydrate groups. The groups had no differences in bench press or squat strength. This study found no differences in muscle mass between those consuming 281 and 380 grams of carbohydrates per day. (Ribeiro et al., 2022)