[@RenaissancePeriodization] We Were Wrong About Carbs for Muscle Growth!? (new study)

Link: https://youtu.be/aPQpAaPW2eo

Duration: 20 min

Transcript: Download plain text

Short Summary

Dr. Mike discusses a meta-analysis by Menno Henselmans and colleagues (11 randomized controlled trials, ~8.5 weeks average duration) finding no statistically significant difference in muscle growth between higher-carb versus higher-fat diets when calories and protein are held constant. The episode provides practical carb-fat ratio optimization protocols, emphasizing that most resistance training doesn't deplete glycogen below 40%, and offers personalized experimentation strategies for both general lifters and professional bodybuilders to find their optimal macronutrient split.

Key Quotes

1. "There was no statistically significant effect on muscle growth of eating more carbs or more fats." (00:00:08)
2. "you want as many carbs as possible has been the claim for a long time." (00:00:41)
3. "Pumps are correlated to muscle hypertrophy. People who get the best pumps typically grow the most." (00:00:24)
4. "you don't have to be all fucking Albert Einstein about it and try to get to which one's 175." (00:00:23)

Detailed Summary

Meta-Analysis Overview

Menno Henselmans and colleagues conducted a meta-analysis comparing carbohydrate and fat intakes across various ratios while keeping calories and protein constant. The analysis included 11 randomized controlled trials with an average sample size of about 20 people per study and an average intervention duration of approximately 8.5 weeks (minimum 6 weeks). The study mostly involved trained lifters, making results most applicable to serious strength athletes rather than untrained beginners.

Key Findings on Muscle Growth

The meta-analysis found no statistically significant effect on muscle growth from eating more carbs versus more fats. However, Dr. Mike clarifies that the study does NOT prove low-carb diets are ideal, nor does it rule out benefits for professional bodybuilders eating high-carb and low-fat for specific performance or hormonal reasons. Participants were roughly at maintenance calories, so findings don't confirm whether more carbs might be better during caloric deficits when glycogen is already being depleted.

Glycogen and Muscle Growth Physiology

Carbohydrates theoretically benefit muscle growth through insulin secretion (reducing protein breakdown), providing workout energy for harder training, and enabling glycogen storage. If glycogen drops below roughly one-third of typical storage, the muscle growth machinery is impaired; however, most resistance training doesn't deplete glycogen below 40%, so this threshold is rarely reached. A practical example shows that eating 3,500 kcal total with 1,000 kcal from protein leaves 2,500 kcal to split between carbs and fats, with both high-carb and high-fat splits supporting similar muscle growth.

Practical Nutrition Recommendations

For muscle growth, consume 4–6 meals per day with high-quality protein (about 1 gram per pound body weight), sufficient fat (about 1/4 to 1/3 gram per pound), and eat above maintenance calories. For a 200 lb person, this means approximately 200g of protein and 50–75g of fat per day. When increasing fat intake, stick to healthy fat sources like nuts, nut butters, and olive/canola oil rather than junk food or high-saturated-fat processed foods.

Personal Optimization Protocol

To find your personal optimal carb-fat ratio: start at 50g carbs per day with the rest as fat for one month, then add 50g carbs every 4 weeks while subtracting 20g of fat each time. Many people have a "personal range of optimality" where 150–250g of carbs produce similar results, with 100g being too low and 300g reducing fat intake so much that sex drive declines. Track strength progression, pumps, soreness, workout energy, sleep quality, and sex drive using the RP Hypertrophy app or RP Diet Coach app.

Testosterone and Fat Connection

Dietary fats support testosterone production—some people maintain good levels at 50g of fat per day while others need around 150g per day. Sex drive serves as a proxy for androgenic hormones like testosterone, which is important for muscle growth. When experimenting with carb/fat ratios, keep calories and protein constant so only one variable changes at a time.

Professional Bodybuilder Considerations

There is no definitive research on optimal carb/fat ratios for pro bodybuilders using growth hormone and insulin, so experimentation is necessary. For pro bodybuilders eating approximately 75g fat and 400g carbs, experiment by dropping to 50g fat with higher carbs, or raising to 100g fat with slightly lower carbs, keeping changes moderate rather than extreme. Many pro bodybuilders discovered that super low-fat diets weren't working; switching to higher fat and lower carbs resulted in significant physique improvements. Pro bodybuilders may find 50–75g of fat per day optimal, with 100g potentially being too few carbs for good gym pumps and recovery.