EFFECTS OF A MULTI-INGREDIENT SUPPLEMENT ON MUSCLE STRENGTH AND HYPERTROPHY IN YOUNG MEN AND WOMEN: A DOUBLE-BLINDED RANDOMIZED CONTROLLED TRIAL

Abstract

Resistance exercise training (RET) is a well-known stimulus for muscle protein synthesis. Protein supplementation, in conjunction with RET, has been shown to yield greater accretion of lean body mass than RET alone. Few studies have compared two multi-ingredient, isonitrogenous supplements of differing quality protein. Therefore, the purpose of the current study was to determine whether there was an augmented effect of a high-quality whey protein multi-ingredient nutritional supplement on hypertrophy in young adults following a RET program. We hypothesized that the multi-ingredient supplement would induce hypertrophy to a greater extent than the control supplement in young adults. Twenty-six (13 male, 13 female) healthy young adults (22 ± 2 years [mean ± SD]) were randomly assigned to either the multi-ingredient nutritional supplement (SUPP, n=12: 20g whey protein, 2g leucine, 2.5g creatine monohydrate, 300mg calcium citrate, 1000IU vitamin D) or control beverage (CON, n=12: 20g collagen protein, 1.4g alanine, 0.6g glycine) groups, ingesting their respective supplements twice daily. Measurements were obtained prior to and after a 10-week linear RET program. Dual-energy X-ray absorptiometry (DXA), ultrasound, one-rep maximum (1RM), and biopsies from the vastus lateralis muscle were performed. A 2-way ANOVA (time by supplement) revealed significantly larger increases in lean body mass (LBM), as assessed via DXA, from the active supplement compared to the control (SUPP: +4.1 ± 1.3kg CON: +2.8 ± 1.7kg, p=0.004). We conclude that the consumption of a multi-ingredient nutritional supplement increased lean body mass to a greater extent than to that observed in the CON group in healthy young adults.