Muscle strength and hypertrophy occur independently of protein supplementation during short-term resistance training in untrained men.
Study Goal
The researchers aimed to determine whether post-exercise protein supplementation (including colostrum) enhances muscle strength and morphology changes during short-term resistance training in untrained men.
Results Summary
The study found no significant differences between the protein supplementation group (containing colostrum) and the placebo group in muscle strength or size improvements, suggesting no additive benefit from the supplement.
Population
Untrained men (N = 18; age 22.0 ± 2.5 years; BMI 25.1 ± 5.4 kg/m²).
Effective Dosage
3 g colostrum (combined with 17 g whey and 2 g leucine) post-exercise.
Duration
4 weeks.
Interactions
None mentioned.
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
short-term resistance training | increase | muscular strength | - | - | has consistently demonstrated gains | #1 |
short-term resistance training | no change | hypertrophy | - | - | has consistently demonstrated gains | #2 |
post-resistance training protein ingestion | increase | muscle size and strength | - | - | is posited to augment the acute anabolic stimulus | #3 |
4 weeks of resistance training with protein supplementation | increase | LP (leg press 1RM strength) | untrained men | - | resulted in significant increases | #4 |
4 weeks of resistance training with protein supplementation | increase | LE (leg extension 1RM strength) | untrained men | - | resulted in significant increases | #5 |
4 weeks of resistance training with protein supplementation | increase | MVIC (maximal isometric knee extensor strength) | untrained men | - | resulted in significant increases | #6 |
4 weeks of resistance training with protein supplementation | increase | RF MT (rectus femoris muscle thickness) | untrained men | - | resulted in significant increases | #7 |
4 weeks of resistance training with protein supplementation | increase | RF CSA (rectus femoris cross-sectional area) | untrained men | - | resulted in significant increases | #8 |
4 weeks of resistance training with protein supplementation | increase | VL MT (vastus lateralis muscle thickness) | untrained men | - | resulted in significant increases | #9 |
4 weeks of resistance training with protein supplementation | increase | VL CSA (vastus lateralis cross-sectional area) | untrained men | - | resulted in significant increases | #10 |
postexercise protein supplementation | no change | muscle strength and size | previously untrained men | - | no additive benefit | #11 |
Short-term resistance training has consistently demonstrated gains in muscular strength, but not hypertrophy. Post-resistance training protein ingestion is posited to augment the acute anabolic stimulus, thus potentially accelerating changes in muscle size and strength. The purpose of this investigation was to examine the effects of 4 weeks of resistance training with protein supplementation on strength and muscle morphology changes in untrained men. Participants (mean ± SD; N = 18; age, 22.0 ± 2.5 years; body mass index, 25.1 ± 5.4 kg · m(-2)) were randomly assigned to a resistance training + protein group (n = 9; whey (17 g) + colostrum (3 g) + leucine (2 g)) or a resistance training + placebo group (n = 9). One-repetition maximum (1RM) strength in the leg press (LP) and leg extension (LE) exercises, maximal isometric knee extensor strength (MVIC), and muscle morphology (thickness (MT), cross-sectional area (CSA), pennation angle) of the dominant rectus femoris (RF) and vastus lateralis (VL) was assessed before and after training. Participants performed LP and LE exercises (3 × 8-10; at 80% 1RM) 3 days/week for 4 weeks. Data were analyzed using 2-way ANOVA with repeated measures. Four weeks of resistance training resulted in significant increases in LP (p < 0.001), LE (p < 0.001), MVIC (p < 0.001), RF MT (p < 0.001), RF CSA (p < 0.001), VL MT (p < 0.001), and VL CSA (p < 0.001). No between-group differences were observed. Although nutrition can significantly affect training adaptations, these results suggest that short-term resistance training augments muscle strength and size in previously untrained men with no additive benefit from postexercise protein supplementation.