Brad Schoenfeld is a professor at Lehman College whose work focuses on exercise science and sports nutrition. His research primarily investigates muscle hypertrophy, body composition, and neuromuscular adaptations to resistance training protocols. His published studies also examine sports nutrition, muscle protein synthesis, and physical fitness metrics.
Dietary protein is much more difficult to convert and store as body fat compared to carbohydrates and dietary fats.
"Protein is very difficult to store as body fat—much more difficult than carbohydrates and fat" (said at 0:27:43)
Biochemically and metabolically, dietary protein requires significantly more energy to process and acutely increases 24-hour and sleeping energy expenditure compared to fat or carbohydrates. However, in terms of whole-body fat accumulation during overfeeding, controlled metabolic trials show that excess total calories drive body fat gain regardless of protein proportion; overfed protein increases energy expenditure and lean mass, but body fat increases similarly across varying protein levels because protein oxidation displaces fat oxidation.
A study demonstrated diminished muscle hypertrophy with a 4-hour eating window and 20-hour fast (4/20) compared to a traditional eating pattern.
"If you're going to do a 4/20, I would say you're then going to be in a lot more—and there's been researchers—one study certainly showed diminished muscle hypertrophy with a 4/20 versus a traditional eating pattern." (said at 0:38:20)
The speaker is referring to the 2017 randomized controlled trial by Tinsley et al. investigating a 4-hour feeding window / 20-hour fast (4 days per week) combined with 8 weeks of resistance training in young men. While the non-fasting control group showed an effect size indicating a gain in lean soft tissue (+2.3 kg) compared to the 4-hour TRF group (+0.0 kg), ultrasound-measured muscle cross-sectional area of the biceps brachii and rectus femoris increased in both groups, and total body composition changes between groups did not reach statistical significance. The TRF protocol also spontaneously reduced daily caloric intake by ~650 kcal, making it difficult to isolate feeding window timing from caloric deficit.
Acute studies demonstrate that omega-3 fatty acid intake has beneficial effects on muscle development, particularly in older adults.
"essential fatty acids, particularly your n-3s, your omega-3 fatty acids, seem to have certain beneficial effects on muscle development, particularly, it seems, for older people, but we don't have great evidence longitudinally. We have some good acute studies that seem to show that." (said at 1:16:44)
The claim is partially accurate: controlled human metabolic studies (using stable isotopes during acute hyperaminoacidemic-hyperinsulinemic clamps after short-term omega-3 supplementation) demonstrate that omega-3 fatty acids enhance the acute muscle protein synthetic response to amino acid and insulin stimulation in older adults, as well as in young and middle-aged adults. However, a broader systematic review and meta-analysis of randomized trials evaluating muscle protein synthesis (MPS) rates found no overall statistically significant pooled effect of omega-3 supplementation specifically on fractional synthetic rates of skeletal muscle, though an effect was observed for whole-body protein synthesis. Therefore, while acute metabolic clamp studies support an anabolic effect under hyperaminoacidemic conditions, the broader synthesized literature shows mixed or conditional findings.
- supports: Dietary omega-3 fatty acid supplementation increases the rate of muscle protein synthesis … (The American journal of clinical nutrition 2011) · cited 662x in the literature
"Omega-3 fatty acid supplementation had no effect on the basal rate of muscle protein synthesis... but augmented the hyperaminoacidemia-hyperinsulinemia-induced increase in the rate of muscle protein synthesis (from 0.009 ± 0.005%/h above basal values to 0.031 ± 0.003%/h above basal values; P < 0.01), which was accompanied by greater increases in muscle mTOR(Ser2448) (P = 0.08) and p70s6k(Thr389) (P < 0.01) phosphorylation." (abstract, results)
pubmedfull study (doi) - context: Omega-3 polyunsaturated fatty acids augment the muscle protein anabolic response to hyperi… (Clinical science (London, England : 1979) 2011) · cited 368x in the literature
"the muscle protein fractional synthesis rate during insulin and amino acid infusion increased from 0.062±0.004 to 0.083±0.007%/h and the phospho-mTOR (Ser2448) and phospho-p70S6K (Thr389) levels increased by ∼50%; all P<0.05" (abstract, results, passage verified)
pubmedfull study (doi) - context: The effects of omega-3 polyunsaturated fatty acids on muscle and whole-body protein synthe… (Nutrition reviews 2025) · cited 39x in the literature
"The main analysis indicated no effect of n-3 PUFA supplementation on MPS rates (k = 6; SMD: 0.03; 95%CI, -0.35 to 0.40; I2 = 30%; P = .89). Subgroup analysis based on age, n-3 PUFA dose, duration of supplementation, and method used to measure fractional synthetic rate also revealed no effect of n-3 PUFA ingestion on MPS. In contrast, the main analysis demonstrated an effect of n-3 PUFA ingestion on increasing whole-body protein synthesis rates (k = 3; SMD: 0.51; 95%CI, 0.12-0.90; I2 = 0%; P = .01)." (abstract, results, passage verified)
pubmedfull study (doi)