In contrast, Verdijk et al. investigated the impact of
the protein, casein hydrolysate, on muscle hypertrophy in healthy untrained elderly men [34]. Researchers randomly assigned 28 elderly men to consume either a protein supplement or a placebo pre- and post-workout. Subjects performed a 12-week resistance weight-training program requiring weightlifting 3 d .wk-1. Crenolanib price Baseline and ending measurements were obtained, including strength assessments, CT scans, DXA scans, blood samples, 24-hour urine samples, muscle biopsies, and immunohistochemistry tests. Results indicated no differences in ending measurements between the protein group and placebo group in muscle hypertrophy, strength, or body composition [34], suggesting that for elderly men, intake of 20 g casein hydrolysate before and after resistance training
does not increase muscle hypertrophy or strength. PF 2341066 In this study, however, only 20 g of casein was used, and it was divided into two servings. This protocol would not have provided participants with the required 3 g of leucine needed to maximize protein synthesis. Additionally, since casein is slow BAY 73-4506 in vitro digesting [44, 45], it may not have been ideal for use in a study of elderly men. Future studies with this population should incorporate whey protein, which is highly bioavailable in an amount that would provide at least 3 g leucine [29, 30]. Studies comparing the effects of supplementation with adequate protein and those with creatine-enhanced protein pre-and post-workout also should be conducted to determine whether creatine is needed to produce the desired outcomes, as has been demonstrated in younger men [33] (See Table 2). The long-term use of whey protein pre- and post- resistance exercise was investigated
by Hulmi et al. [35], by assigning participants to one of three groups:1) 15 g of whey protein before and after resistance exercise, 2) a placebo before and after resistance exercise, or 3) no supplement no participation in weightlifting but continued habitual exercise as they did prior to the study. Participants in the first two groups completed two resistance exercise sessions per week for 21 weeks consisting of both upper FAD and lower body multi-joint lifts. All participants then had biopsies performed on their vastus lateralis. Results indicated that the whey protein group had significantly greater increases than the other groups in vastus lateralis hypertrophy, and greater overall muscle hypertrophy [35]. These findings provide evidence that whey protein supplementation pre- and post-workout is useful in increasing muscle hypertrophy. Andersen et al. examined the effects of a mixed blend of proteins on muscle strength and muscle fiber size [36].