Effects of Icelandic yogurt consumption and resistance training in healthy untrained older males

Due to the important roles of resistance training and protein consumption in the prevention and treatment of sarcopenia, we assessed the efficacy of post-exercise Icelandic yogurt consumption on lean mass, strength, and skeletal muscle regulatory factors in healthy untrained older males. Thirty healthy untrained older males (age = 68 ± 4 yr) were randomly assigned to Icelandic yogurt (IR; n =15, 18 g of protein) or an iso-energetic placebo (PR; n =15, 0 g protein) immediately following resistance training (3x/week) for eight weeks. Before and after training, lean mass, strength, and skeletal muscle regulatory factors (insulin-like growth factor-1 [IGF-1], transforming growth factor-beta 1 [TGF-β1], growth differentiation factor 15 [GDF15], Activin A, myostatin [MST], and follistatin [FST]) were assessed. There were group x time interactions (p < 0.05) for body mass (IR: Δ 1, PR: Δ 0.7 kg), body mass index (IR: Δ 0.3, PR: Δ 0.2 kg∙m-2), lean mass (IR: Δ 1.3, PR: Δ 0.6 kg), bench press (IR: Δ 4, PR: 2.3 kg), leg press (IR: Δ 4.2, PR: Δ 2.5 kg), IGF-1 (IR: Δ 0.5, Δ PR: 0.1 ng∙mL-1), TGF-β (IR: Δ -0.2, PR: Δ -0.1 ng∙mL-1), GDF15 (IR: Δ -10.3, PR: Δ -4.8 pg∙mL-1), Activin A (IR: Δ -9.8, PR: Δ -2.9 pg∙mL-1), MST (IR: Δ -0.1, PR: Δ -0.04 ng∙mL-1), and FST (IR: Δ 0.09, PR: Δ 0.03 ng∙mL-1), with Icelandic yogurt consumption resulting in greater changes compared to placebo. The addition of Icelandic yogurt consumption to a resistance training program improved lean mass, strength, and altered skeletal muscle regulatory factors in healthy untrained older males compared to placebo. Therefore, Icelandic yogurt as a nutrient-dense source and cost-effective supplement enhances muscular gains mediated by resistance training and consequently may be used as a strategy for the prevention of sarcopenia

Effects of Dietary Protein on Body Composition in Exercising Individuals

Protein is an important component of a healthy diet and appears to be integral to enhancing training adaptations in exercising individuals. The purpose of this narrative review is to provide an evidence-based assessment of the current literature examining increases in dietary protein intake above the recommended dietary allowance (RDA: 0.8 g/kg/d) in conjunction with chronic exercise on body composition (i.e., muscle, fat and bone). We also highlight acute and chronic pre-sleep protein studies as well as the influence of exercise timing on body composition. Overall, a high-protein diet appears to increase muscle accretion and fat loss and may have beneficial effects on bone when combined with exercise. Pre-sleep protein is a viable strategy to help achieve total daily protein goals. Importantly, there appears to be no deleterious effects from a high-protein diet on muscle, fat or bone in exercising individuals

Creatine O'Clock: Does Timing of Ingestion Really Influence Muscle Mass and Performance?

It is well-established that creatine supplementation augments the gains in muscle mass and performance during periods of resistance training. However, whether the timing of creatine ingestion influences these physical and physiological adaptations is unclear. Muscle contractions increase blood flow and possibly creatine transport kinetics which has led some to speculate that creatine in close proximity to resistance training sessions may lead to superior improvements in muscle mass and performance. Furthermore, creatine co-ingested with carbohydrates or a mixture of carbohydrates and protein that alter insulin enhance creatine uptake. The purpose of this narrative review is to (i) discuss the purported mechanisms and variables that possibly justify creatine timing strategies, (ii) to critically evaluate research examining the strategic ingestion of creatine during a resistance training program, and (iii) provide future research directions pertaining to creatine timing

Effects of Creatine Supplementation on Brain Function and Health

While the vast majority of research involving creatine supplementation has focused on skeletal muscle, there is a small body of accumulating research that has focused on creatine and the brain. Preliminary studies indicate that creatine supplementation (and guanidinoacetic acid; GAA) has the ability to increase brain creatine content in humans. Furthermore, creatine has shown some promise for attenuating symptoms of concussion, mild traumatic brain injury and depression but its effect on neurodegenerative diseases appears to be lacking. The purpose of this narrative review is to summarize the current body of research pertaining to creatine supplementation on total creatine and phophorylcreatine (PCr) content, explore GAA as an alternative or adjunct to creatine supplementation on brain creatine uptake, assess the impact of creatine on cognition with a focus on sleep deprivation, discuss the effects of creatine supplementation on a variety of neurological and mental health conditions, and outline recent advances on creatine supplementation as a neuroprotective supplement following traumatic brain injury or concussion

Dietary Supplements and Sports Performance: Amino Acids

This is the third in a series of six articles to discuss the major classes of dietary supplements (vitamins; minerals; amino acids; herbs or botanicals; metabolites, constituents/extracts, or combinations). The major focus is on efficacy of such dietary supplements to enhance exercise or sport performance

Resistance training with soy vs whey protein supplements in hyperlipidemic males

<p>Abstract</p> <p>Background</p> <p>Most individuals at risk for developing cardiovascular disease (CVD) can reduce risk factors through diet and exercise before resorting to drug treatment. The effect of a combination of resistance training with vegetable-based (soy) versus animal-based (whey) protein supplementation on CVD risk reduction has received little study. The study's purpose was to examine the effects of 12 weeks of resistance exercise training with soy versus whey protein supplementation on strength gains, body composition and serum lipid changes in overweight, hyperlipidemic men.</p> <p>Methods</p> <p>Twenty-eight overweight, male subjects (BMI 25–30) with serum cholesterol >200 mg/dl were randomly divided into 3 groups (placebo (n = 9), and soy (n = 9) or whey (n = 10) supplementation) and participated in supervised resistance training for 12 weeks. Supplements were provided in a double blind fashion.</p> <p>Results</p> <p>All 3 groups had significant gains in strength, averaging 47% in all major muscle groups and significant increases in fat free mass (2.6%), with no difference among groups. Percent body fat and waist-to-hip ratio decreased significantly in all 3 groups an average of 8% and 2%, respectively, with no difference among groups. Total serum cholesterol decreased significantly, again with no difference among groups.</p> <p>Conclusion</p> <p>Participation in a 12 week resistance exercise training program significantly increased strength and improved both body composition and serum cholesterol in overweight, hypercholesterolemic men with no added benefit from protein supplementation.</p

A whey protein-based multi-ingredient nutritional supplement stimulates gains in lean body mass and strength in healthy older men: A randomized controlled trial

Protein and other compounds can exert anabolic effects on skeletal muscle, particularly in conjunction with exercise. The objective of this study was to evaluate the efficacy of twice daily consumption of a protein-based, multi-ingredient nutritional supplement to increase strength and lean mass independent of, and in combination with, exercise in healthy older men. Forty-nine healthy older men (age: 73 ± 1 years [mean ± SEM]; BMI: 28.5 ± 1.5 kg/m2) were randomly allocated to 20 weeks of twice daily consumption of either a nutritional supplement (SUPP; n = 25; 30 g whey protein, 2.5 g creatine, 500 IU vitamin D, 400 mg calcium, and 1500 mg n-3 PUFA with 700 mg as eicosapentanoic acid and 445 mg as docosahexanoic acid); or a control (n = 24; CON; 22 g of maltodextrin). The study had two phases. Phase 1 was 6 weeks of SUPP or CON alone. Phase 2 was a 12 week continuation of the SUPP/CON but in combination with exercise: SUPP + EX or CON + EX. Isotonic strength (one repetition maximum [1RM]) and lean body mass (LBM) were the primary outcomes. In Phase 1 only the SUPP group gained strength (Σ1RM, SUPP: +14 ± 4 kg, CON: +3 ± 2 kg, P < 0.001) and lean mass (LBM, +1.2 ± 0.3 kg, CON: -0.1 ± 0.2 kg, P < 0.001). Although both groups gained strength during Phase 2, upon completion of the study upper body strength was greater in the SUPP group compared to the CON group (Σ upper body 1RM: 119 ± 4 vs. 109 ± 5 kg, P = 0.039). We conclude that twice daily consumption of a multi-ingredient nutritional supplement increased muscle strength and lean mass in older men. Increases in strength were enhanced further with exercise training

Ageing, Muscle Power and Physical Function: A Systematic Review and Implications for Pragmatic Training Interventions.

BACKGROUND: The physiological impairments most strongly associated with functional performance in older people are logically the most efficient therapeutic targets for exercise training interventions aimed at improving function and maintaining independence in later life. OBJECTIVES: The objectives of this review were to (1) systematically review the relationship between muscle power and functional performance in older people; (2) systematically review the effect of power training (PT) interventions on functional performance in older people; and (3) identify components of successful PT interventions relevant to pragmatic trials by scoping the literature. METHODS: Our approach involved three stages. First, we systematically reviewed evidence on the relationship between muscle power, muscle strength and functional performance and, second, we systematically reviewed PT intervention studies that included both muscle power and at least one index of functional performance as outcome measures. Finally, taking a strong pragmatic perspective, we conducted a scoping review of the PT evidence to identify the successful components of training interventions needed to provide a minimally effective training dose to improve physical function. RESULTS: Evidence from 44 studies revealed a positive association between muscle power and indices of physical function, and that muscle power is a marginally superior predictor of functional performance than muscle strength. Nine studies revealed maximal angular velocity of movement, an important component of muscle power, to be positively associated with functional performance and a better predictor of functional performance than muscle strength. We identified 31 PT studies, characterised by small sample sizes and incomplete reporting of interventions, resulting in less than one-in-five studies judged as having a low risk of bias. Thirteen studies compared traditional resistance training with PT, with ten studies reporting the superiority of PT for either muscle power or functional performance. Further studies demonstrated the efficacy of various methods of resistance and functional task PT on muscle power and functional performance, including low-load PT and low-volume interventions. CONCLUSIONS: Maximal intended movement velocity, low training load, simple training methods, low-volume training and low-frequency training were revealed as components offering potential for the development of a pragmatic intervention. Additionally, the research area is dominated by short-term interventions producing short-term gains with little consideration of the long-term maintenance of functional performance. We believe the area would benefit from larger and higher-quality studies and consideration of optimal long-term strategies to develop and maintain muscle power and physical function over years rather than weeks