Negligible Effects of β-Hydroxy-β-Methylbutyrate Free Acid and Calcium Salt on Strength and Hypertrophic Responses to Resistance Training: A Randomized, Placebo-Controlled Study.
Study Goal
The researchers aimed to compare the effects of HMB-FA and HMB-Ca (calcium salt form) on strength, hypertrophy, and muscle damage markers in resistance-trained men.
Results Summary
Neither HMB-Ca nor HMB-FA improved hypertrophy or reduced muscle damage, though HMB-FA showed a minor but statistically significant improvement in leg press strength compared to HMB-Ca and placebo. All groups saw increases in lean body mass, cross-sectional area, and strength, with no significant differences between supplement groups.
Population
44 resistance-trained men (age 26 ± 4 years, body mass 84.9 ± 12.0 kg) consuming ≥1.7 g·kg-1·day-1 of protein.
Effective Dosage
3 g/day of HMB-FA or HMB-Ca.
Duration
12 weeks.
Interactions
None mentioned.
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
β-hydroxy-β-methylbutyrate free acid (HMB-FA) | increase | lean body mass | 44 resistance-trained men | 1.8 ± 1.8 kg | increased | #1 |
β-hydroxy-β-methylbutyrate calcium salt (HMB-Ca) | increase | lean body mass | 44 resistance-trained men | 0.8 ± 1.4 kg | increased | #2 |
placebo (cornstarch) | increase | lean body mass | 44 resistance-trained men | 0.9 ± 1.4 kg | increased | #3 |
β-hydroxy-β-methylbutyrate free acid (HMB-FA) | increase | cross-sectional area | 44 resistance-trained men | 6.6 ± 3.8% | increased | #4 |
β-hydroxy-β-methylbutyrate calcium salt (HMB-Ca) | increase | cross-sectional area | 44 resistance-trained men | 4.7 ± 4.4% | increased | #5 |
placebo (cornstarch) | increase | cross-sectional area | 44 resistance-trained men | 6.9 ± 3.8% | increased | #6 |
β-hydroxy-β-methylbutyrate free acid (HMB-FA) | increase | one-repetition maximum bench press | 44 resistance-trained men | 14.8 ± 8.4 kg | increased | #7 |
β-hydroxy-β-methylbutyrate calcium salt (HMB-Ca) | increase | one-repetition maximum bench press | 44 resistance-trained men | 11.8 ± 7.4 kg | increased | #8 |
placebo (cornstarch) | increase | one-repetition maximum bench press | 44 resistance-trained men | 11.2 ± 6.6 kg | increased | #9 |
β-hydroxy-β-methylbutyrate free acid (HMB-FA) | increase | maximal voluntary isometric contraction (MVIC) | 44 resistance-trained men | 34.4 ± 39.3% | increased | #10 |
β-hydroxy-β-methylbutyrate calcium salt (HMB-Ca) | increase | maximal voluntary isometric contraction (MVIC) | 44 resistance-trained men | 32.3 ± 27.4% | increased | #11 |
placebo (cornstarch) | increase | maximal voluntary isometric contraction (MVIC) | 44 resistance-trained men | 17.7 ± 20.9% | increased | #12 |
β-hydroxy-β-methylbutyrate free acid (HMB-FA) | increase | leg press strength | 44 resistance-trained men | 47.7 ± 31.2 kg | showed greater | #13 |
β-hydroxy-β-methylbutyrate calcium salt (HMB-Ca) | increase | leg press strength | 44 resistance-trained men | 43.8 ± 31.7 kg | showed | #14 |
placebo (cornstarch) | increase | leg press strength | 44 resistance-trained men | 30.2 ± 20.9 kg | showed | #15 |
β-hydroxy-β-methylbutyrate free acid (HMB-FA) | no change | MVIC measured 48 hr after training sessions | 44 resistance-trained men | - | showed no attenuation of force decline | #16 |
β-hydroxy-β-methylbutyrate calcium salt (HMB-Ca) | no change | MVIC measured 48 hr after training sessions | 44 resistance-trained men | - | showed no attenuation of force decline | #17 |
β-hydroxy-β-methylbutyrate free acid (HMB-FA) | no change | muscle soreness following training sessions | 44 resistance-trained men | - | was not different | #18 |
β-hydroxy-β-methylbutyrate calcium salt (HMB-Ca) | no change | muscle soreness following training sessions | 44 resistance-trained men | - | was not different | #19 |
β-hydroxy-β-methylbutyrate calcium salt (HMB-Ca) | no change | hypertrophy | resistance-trained men | - | neither ... improved | #20 |
β-hydroxy-β-methylbutyrate free acid (HMB-FA) | no change | hypertrophy | resistance-trained men | - | neither ... improved | #21 |
β-hydroxy-β-methylbutyrate calcium salt (HMB-Ca) | no change | muscle damage | resistance-trained men | - | neither ... reduced | #22 |
β-hydroxy-β-methylbutyrate free acid (HMB-FA) | no change | muscle damage | resistance-trained men | - | neither ... reduced | #23 |
β-hydroxy-β-methylbutyrate free acid (HMB-FA) | increase | leg press one-repetition maximum | resistance-trained men | - | resulted in a statistically significant yet minor improvement | #24 |
β-hydroxy-β-methylbutyrate calcium salt (HMB-Ca) | no change | leg press one-repetition maximum | resistance-trained men | - | not ... resulted in a statistically significant yet minor improvement | #25 |
This study evaluated the effects of β-hydroxy-β-methylbutyrate free acid (HMB-FA) and calcium salt (HMB-Ca) on strength, hypertrophy, and markers of muscle damage. In this randomized, double-blind, placebo-controlled study, 44 resistance-trained men (age: 26 ± 4 years; body mass: 84.9 ± 12.0 kg) consuming ≥1.7 g·kg-1·day-1 of protein received HMB-FA (3 g/day; n = 14), HMB-Ca (3 g/day; n = 15), or placebo (PL; cornstarch, 3 g/day; n = 15) for 12 weeks, while performing a periodized resistance training program. Before and after intervention, lean body mass (measured with dual X-ray absorptiometry), maximal dynamic strength (one-repetition maximum), knee extension maximal isometric strength (maximal voluntary isometric contraction [MVIC]), cross-sectional area (measured with ultrasound), and muscle soreness were assessed. MVIC was also measured 48 hr after the first and the last training sessions. All groups increased lean body mass (main time effect: p < .0001; HMB-FA: 1.8 ± 1.8 kg; HMB-Ca: 0.8 ± 1.4 kg; PL: 0.9 ± 1.4 kg), cross-sectional area (main time effect: p < .0001; HMB-FA: 6.6 ± 3.8%; HMB-Ca: 4.7 ± 4.4%; PL: 6.9 ± 3.8%), one-repetition maximum bench press (main time effect: p < .0001; HMB-FA: 14.8 ± 8.4 kg; HMB-Ca: 11.8 ± 7.4 kg; PL: 11.2 ± 6.6 kg), MVIC (main time effect: p < .0001; HMB-FA: 34.4 ± 39.3%; HMB-Ca: 32.3 ± 27.4%; PL: 17.7 ± 20.9%) after the intervention, but no differences between groups were shown. HMB-FA group showed greater leg press strength after the intervention than HMB-Ca and PL groups (Group × Time interaction: p < .05; HMB-FA: 47.7 ± 31.2 kg; HMB-Ca: 43.8 ± 31.7 kg; PL: 30.2 ± 20.9 kg). MVIC measured 48 hr after the first and the last sessions showed no attenuation of force decline with supplementation. Muscle soreness following the first and last sessions was not different between groups. The authors concluded that neither HMB-Ca nor HMB-FA improved hypertrophy or reduced muscle damage in resistance-trained men undergoing resistance training ingesting optimal amounts of protein. HMB-FA but not HMB-Ca resulted in a statistically significant yet minor improvement on leg press one-repetition maximum.