I Tested 3 Muscle Building Diets... Only 1 Was Worth It
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How much muscle can you really build in 90 days without gaining fat? Testing three popular muscle building diets on brother-in-law Dayton. Last year, Dayton dropped from 33% body fat to 17%. Now he wants to bulk up without getting fat again. > Now that I've cut, I really want to bulk up, get bigger at all. I'm not getting fat again. Like, I refuse to get fat again.
Theory: Train hard while eating at maintenance calories (2300 for Dayton) to burn body fat for muscle growth. Measurements: DEXA scans before/after each diet, plus ultrasounds, skinfolds, circumference for reliability. Maintenance calculation: body weight in pounds × 13-16 based on activity. Protein: at least 100g/day (body weight in pounds × 0.7), enough for gains if calories sufficient and not shredded bodybuilder. Allows more carbs for workouts. Sample day hits 2300 calories with veggies, lean protein, carbs.
I got my veggies, lean protein, and my carbs. We're 7 days in. My weight hasn't moved. We're doing good.
Training: 5 days/week using favorite workout split. Dayton hits PRs every workout, tracked via app to correlate strength with muscle growth.
Roommates moving out, business dry spell, stress leads to more snacking. Holidays with Filipino desserts like ube and rice pudding. > I got my third plate of the night, a dessert. It's called ube and then some sort of rice pudding. Grandpa passed away from cancer; was father figure after dad died at age 7 from cancer. Tough time for family, but Dayton didn't miss workouts.
Gained 2lb instead of maintaining. Switched order: next is lean bulk (maintenance +250 calories, ~2lb gain/month). Saved main gaining for end. After 30 days lean bulking: +1.35lb muscle (above average; 2020 meta-analysis: 2.4lb muscle in 10 weeks for short-term studies). Personal rate: 0.5lb in 60 days. Some fat gain but not excessive (belly skinfolds, ultrasound, waist).
Calories to 2800 (+500 over maintenance). Add calories from pure carbs for glycogen and workout energy. Small changes: more rice, carbs, sauce, but weigh everything. PRs increase, more energy, adds extra sets (unlike controlled studies). Business improves via TikTok fitness videos driving orders. Brother moves in as roommate.
You're getting enough protein. So, my personal recommendation is if you're going to add calories, let's do it from just pure carbs. Cuz that's what's going to give you the glycogen and the energy that you need in your workouts.
Notices extra belly fat and face weight.
Study on untrained: fast bulk yields huge muscle gains, minimal fat in 8 weeks. Experienced lifters: more fat than muscle. Works best for beginners who use extra calories for muscle. Personal anecdote: dirty bulk (gallon of milk/day) worked first time as beginner, later caused fluffiness requiring months to cut with little muscle. Dayton: first year proper training, gained 4lb in 30 days. > Strength, overall size. I just feel bigger. I have more energy. I feel strong. Definitely did. I've noticed a little bit of fat gain, but that was to be expected. Pull-up strength doubled. Results: +1.8lb muscle (30% more than lean bulk), but 3x more fat.
Back to maintenance, no more ground beef—switch to chicken, jerky. Theory: Tap body fat stores (>100k calories) for muscle growth energy. Prior example: Dayton built 0.7lb muscle/month while losing 5lb fat/month on cut. Common in studies and app members, even experienced trainees with proper plans. App: Personalized diet/training based on info, adjusts over time. Free 2 weeks at buildwithscience.com.
Creative hacks: Mix extra lean ground beef with lean turkey for flavor. Chocolate peanut butter frozen yogurt snack with banana (tastes like Reese's). New roommate (brother Cole): Train together, hit PRs (24 dips), prep meals, accountability.
I've been working out the last year and a half. Before that, I was an addict for 10 years, living on the streets, getting in trouble. Uh, pretty much weighed nothing. Now look at me. After dealing with the loss of my grandfather. It's really got me thinking about family, how uh me and my brother lost my parents at a young age. I really haven't had my brother in my life for about 10 years due to his own struggles. So, I'm just really happy that he's uh doing better and he's going to be living here.
Weight stable. Strength up in 6-12 rep range indicates muscle growth despite scale. Not for <15% BF men/25% women, underweight, or very lean/advanced. Good if enough BF, new to training, or never trained/dieted properly—avoids bulk/cut cycles.
All with dumbbells, bench, pull-up bar. Surprise: barbell, weight plates, more coming for Dayton and brother. Final 30 days: +1.1lb muscle (15% less than lean bulk, 37% less than fast bulk). Total 90 days: ~4.4lb muscle. Strength gains match muscle built—track lifts if no scans. Fat: Lost some, waist tighter, belly fat reduced.
Fast bulk: most muscle but disproportionate fat. Main gaining: surprised by muscle built, lost fat. For Dayton (prioritizes muscle before 12% cut): lean bulk best now. Chart guides based on body. All diets yielded progress—don't overthink, eat well/train hard. Dayton sticks with leaner bulk to avoid excess belly fat for easier 12% cut.
I think if we stick to that, I don't get too much belly fat over the next few months, then I can hit that 12% easier. Won't feel like I'm giving up so much.
Surprise gym setup. > Yo, you went overboard, dude.
Amazing. I mean, my whole life changed for so many positive ways. just diet, my energy, everything's just been overall better. And it's thanks to you and your app. It's just so nice to not have to overthink. It's just it does all the little things, the monotonous stuff that no one wants to do. It just takes care of all of that. App: 2 weeks free at buildwithscience.com. Full body workout plan video.
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