Effects of pre- or post-exercise whey protein supplementation on body fat and metabolic and inflammatory profile in pre-conditioned older women: A randomized, double-blind, placebo-controlled trial.
Study Goal
The researchers aimed to determine whether whey protein supplementation before or after resistance training improves metabolic and inflammatory profiles in older women.
Results Summary
Whey protein supplementation, whether taken before or after resistance training, led to greater improvements in appendicular lean soft tissue and cholesterol ratios compared to placebo. Post-resistance training whey protein also showed additional benefits in reducing body fat and improving metabolic health.
Population
Pre-conditioned older women (n=70)
Effective Dosage
35 g of whey protein or placebo pre- and post-resistance training
Duration
12 weeks
Interactions
None mentioned
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
whey protein pre- or post-resistance training | increase | appendicular lean soft tissue | pre-conditioned older women | - | promotes improvements | #1 |
whey protein pre- or post-resistance training | decrease | total cholesterol/high density lipoprotein cholesterol ratio | pre-conditioned older women | - | promotes improvements | #2 |
whey protein pre-resistance training and placebo post-resistance training | increase | appendicular lean soft tissue | pre-conditioned older women | 3.1% | showed greater improvements | #3 |
placebo pre-resistance training and whey protein post-resistance training | increase | appendicular lean soft tissue | pre-conditioned older women | 3.9% | showed greater improvements | #4 |
placebo pre and post-resistance training | increase | appendicular lean soft tissue | pre-conditioned older women | 1.8% | showed greater improvements | #5 |
whey protein pre-resistance training and placebo post-resistance training | decrease | total cholesterol/high density lipoprotein cholesterol ratio | pre-conditioned older women | -12.11% | showed greater improvements | #6 |
placebo pre-resistance training and whey protein post-resistance training | decrease | total cholesterol/high density lipoprotein cholesterol ratio | pre-conditioned older women | -13.2% | showed greater improvements | #7 |
placebo pre and post-resistance training | decrease | total cholesterol/high density lipoprotein cholesterol ratio | pre-conditioned older women | -0.7% | showed greater improvements | #8 |
whey protein post-resistance training | increase | appendicular lean soft tissue/appendicular fat mass ratio | pre-conditioned older women | 5.8% | showed improvements | #9 |
placebo pre and post-resistance training | increase | appendicular lean soft tissue/appendicular fat mass ratio | pre-conditioned older women | 1.3% | showed improvements | #10 |
whey protein post-resistance training | decrease | total body fat | pre-conditioned older women | -3.8% | showed improvements | #11 |
placebo pre and post-resistance training | decrease | total body fat | pre-conditioned older women | -0.1% | showed improvements | #12 |
whey protein post-resistance training | decrease | trunk fat mass | pre-conditioned older women | -3.1% | showed improvements | #13 |
placebo pre and post-resistance training | decrease | trunk fat mass | pre-conditioned older women | -0.3% | showed improvements | #14 |
whey protein administered after resistance training | increase | metabolic health Z-score | pre-conditioned older women | - | was more effective in improving | #15 |
whey protein administered after resistance training | decrease | body fat | pre-conditioned older women | - | was more effective in reducing | #16 |
BACKGROUND AND AIM: Protein supplementation and resistance training (RT) are interventions that may counteract decline in muscle mass and increase in fat mass, thus reducing the risk of developing chronic diseases during the aging process. The objective of this study was to investigate the effect of whey protein (WP) pre- or post-RT on metabolic and inflammatory profile in pre-conditioned older women. METHODS AND RESULTS: Seventy older women participated in this investigation and were randomly assigned to one of three groups: WP pre-RT and placebo post-RT (WP-PLA, n = 24), placebo pre-RT and WP post-RT (PLA-WP, n = 23) and placebo pre and post-RT (PLA-PLA, n = 23). Each group ingested 35 g of PLA or WP pre- and post-RT. RT was carried out over 12 weeks (three times/week; 3 x 8-12 repetition maximum). Body composition, blood pressure, blood samples and dietary intake were assessed pre- and post-intervention. After the intervention, WP groups showed greater improvements in appendicular lean soft tissue (ALST: WP-PLA, 3.1%; PLA-WP, 3.9%; PLA-PLA, 1.8%) and total cholesterol/high density lipoprotein cholesterol ratio (TC/HDL-C: WP-PLA, -12.11%; PLA-WP, -13.2%; PLA-PLA, -0.7) when compared with PLA-PLA. WP post-RT also showed improvements (P < 0.05) in ALST/appendicular fat mass ratio (PLA-WP, 5.8%; PLA-PLA, 1.3%), total body fat (PLA-WP, -3.8%; PLA-PLA: -0.1) and trunk fat mass (PLA-WP, -3.1%; PLA-PLA, -0.3%) when compared with PLA-PLA. CONCLUSION: WP pre- or post- RT promotes improvements in ALST and TC/HDL-C ratio in pre-conditioned older women. WP administered after RT was more effective in improving metabolic health Z-score and in reducing body fat compared to placebo group.