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Abstract The purpose of this review was to determine whether past research provides conclusive evidence about the effects of type and timing of ingestion of specific sources of protein by those engaged in resistance weight training. Two essential, nutrition-related, tenets need to be followed by weightlifters to maximize muscle hypertrophy: the consumption of 1.2-2.0 g protein.kg -1 of body weight, and ≥44-50 kcal.kg-1 of body weight. Researchers have tested the effects of timing of protein supplement ingestion on various physical changes in weightlifters. In general, protein supplementation pre- and post-workout increases physical performance, training session recovery, lean body mass, muscle hypertrophy, and strength. Specific gains, differ however based on protein type and amounts. Studies on timing of consumption of milk have indicated that fat-free milk post-workout was effective in promoting increases in lean body mass, strength, muscle hypertrophy and decreases in body fat. The leucine content of a protein source has an impact on protein synthesis, and affects muscle hypertrophy. Consumption of 3–4 g of leucine is needed to promote maximum protein synthesis. An ideal supplement following resistance exercise should contain whey protein that provides at least 3 g of leucine per serving. A combination of a fast-acting carbohydrate source such as maltodextrin or glucose should be consumed with the protein source, as leucine cannot modulate protein synthesis as effectively without the presence of insulin. Such a supplement post-workout would be most effective in increasing muscle protein synthesis, resulting in greater muscle hypertrophy and strength. In contrast, the consumption of essential amino acids and dextrose appears to be most effective at evoking protein synthesis prior to rather than following resistance exercise. To further enhance muscle hypertrophy and strength, a resistance weight- training program of at least 10–12 weeks with compound movements for both upper and lower body exercises should be followed.

Abstract Background β-Alanine (βA) has been shown to improve performance during cycling. This study was the first to examine the effects of βA supplementation on the onset of blood lactate accumulation (OBLA) during incremental treadmill running. Methods Seventeen recreationally-active men (mean ± SE 24.9 ± 4.7 yrs, 180.6 ± 8.9 cm, 79.25 ± 9.0 kg) participated in this randomized, double-blind, placebo-controlled pre/post test 2-treatment experimental design. Subjects participated in two incremental treadmill tests before and after 28 days of supplementation with either βA (6.0 g·d-1)(βA, n = 8) or an equivalent dose of Maltodextrin as the Placebo (PL, n = 9). Heart rate, percent heart rate maximum (%HRmax), %VO2max@OBLA (4.0 mmol.L-1 blood lactate concentration) and VO2max (L.min-1) were determined for each treadmill test. Friedman test was used to determine within group differences; and Mann-Whitney was used to determine between group differences for pre and post values (p < 0.05). Results The βA group experienced a significant rightward shift in HR@OBLA beats.min-1 (p < 0.01) pre/post (161.6 ± 19.2 to 173.6 ± 9.9) but remained unchanged in the PL group (166.8 ± 15.8 to 169.6 ± 16.1). The %HRmax@OBLA increased (p < 0.05) pre/post in the βA group (83.0% ± 9.7 to 88.6% ± 3.7) versus no change in the PL group (86.3 ± % 4.8 to 87.9% ± 7.2). The %VO2max@OBLA increased (p < 0.05) in the βA group pre/post (69.1 ± 11.0 to 75.6 ± 10.7) but remained unchanged in the PL group (73.3 ± 7.3 to 74.3 ± 7.3). VO2max (L.min-1) decreased (p < 0.01) in the βA group pre/post (4.57 ± 0.8 to 4.31 ± 0.8) versus no change in the PL group (4.04 ± 0.7 to 4.18 ± 0.8). Body mass kg increased (p < 0.05) in the βA group pre/post (77.9 ± 9.0 to 78.3 ± 9.3) while the PL group was unchanged (80.6 ± 9.1 to 80.4 ± 9.0). Conclusions βA supplementation for 28 days enhanced sub-maximal endurance performance by delaying OBLA. However, βA supplemented individuals had a reduced aerobic capacity as evidenced by the decrease in VO2max values post supplementation.

Protein supplements commonly are ingested by athletes to improve strength, agility, and speed. While athletes require a higher amount of protein (g*[kg.sup.-1] body weight) than nonathletes do to support protein synthesis, they do not necessarily need to consume protein from supplemental sources. To date, no studies have shown an advantage of ingesting protein supplements over natural, protein-containing foods; therefore, dietary sources of protein may be just as effective as protein supplemental sources in the regulation of muscle protein synthesis. Misconceptions regarding protein supplement effectiveness may originate from athletes' nutrition information sources. A survey questionnaire queried high school football players about sources of information and measured protein supplement misconceptions by using scores on a Protein Supplement Misconceptions Index. Sixty-one high school football players participated in the study; 39 were protein supplementers, and 22 were non--protein supplementers. There was a significant difference between index scores of protein supplementers and non--protein supplementers (t = -3.4, p = 0.001), indicating that protein supplementers had a greater level of misconceptions than non-protein supplementers did. Bonferroni post hoc procedures used with individual index items revealed that protein supplementers were more likely than non-protein supplementers to agree that 'athletes should take protein supplements' (p = 0.001) and needed them 'to gain as much muscle as possible' (p = 0.001 ). Greater misconceptions for protein supplementers may have resulted from the sources chosen for information and advice. Since coaches, parents, and friends were the primary sources of advice about protein supplements for protein supplementers, it would be valuable to provide nutrition education to these groups concurrently with educating young athletes to dispel ongoing misconceptions regarding the need for and effectiveness of protein supplements. KEY WORDS sports nutrition, ergogenic aids, resistance training

Long-haul truckers are confined, by parking regulations and other constraints, to dining at truck-stop restaurants. Objectives were to (a) compare truckers' anthropometrics with recommended guidelines; and (b) assess eating/exercise habits, importance of healthful food choices, and attitudes about restaurants' provision of healthful options. Hypotheses were: (a) overweight/obese drivers will place less importance on healthful food choices than will drivers of optimal weight; (b) importance of healthful food choices and attitudes about their provision will be positively correlated. Questionnaires included Food Choices Index, Nutrition Attitude Survey, and demographic information; bioelectrical impedance assessed weight, body fat, and body mass index. Subjects (n=92) were truckers at a Midwestern truck-stop restaurant; 79 were overweight, 52 were obese. Mean rating of importance of healthful choices was above average. There was no difference in importance of healthful food choices for overweight/obese and optimal weight drivers, t(89)=-1.312; P=0.19. Drivers placing more importance on healthful food choices had more positive attitudes about restaurants' provision of such options, r(90)=0.74, P<0.001. Overall, drivers indicated they would choose healthful foods if available and appetizing. Registered dietitian-directed wellness programs that include education, support, and cooperation of truck-stop restaurants are critical to reduce obesity and risk of disease in this population.

Calcium from dairy sources is beneficial to weight loss; however, no studies have compared the effects of dairy to nondairy sources of calcium on weight loss. This pilot study explored differences between soy and skim milk on changes in anthropometric values in premenopausal women. In a prospective randomized controlled trial, 14 women with overweight/obesity were randomly assigned to 720 mL soy milk (n=7) or an equivalent volume of skim milk (n=7) daily for 8 weeks. Subjects followed a 500-kcal deficit diet based on metabolic rate data. There were no anthropometric differences between soy and skim milk groups at baseline. Subjects followed an energy-restricted diet; both groups experienced reductions in kilogram weight (4.27 [+ or -] 2.05 vs 3.76 [+ or -] 2.25; P=0.668), body fat percent (1.30 [+ or -] 1.37 vs 1.87 [+ or -] 1.45; P=0.464), and abdominal circumference (11.28 [+ or -] 5.23 vs 8.66 [+ or -] 2.51; P=0.259) while attenuating losses of fat-free mass (1.12 [+ or -] 1.29 vs 0.43 [+ or -] 1.12; P=0.299) during the 8-week study. There were no significant differences in weight, fat percent, abdominal circumference, and fat-free mass between groups. To optimize the weight loss effects of calcium, one can consume 720 mL of either soy milk or skim milk daily.

This study examined the effects that preceding creatine supplementation with a lacto-ovo-vegetarian diet would have on plasma creatine concentration. Twenty-six healthy moderately fit omnivorous men were assigned to either a 26-day lacto-ovo-vegetarian (LOV; n = 12) or omnivorous (Omni; n = 14) diet. On day 22, subjects were also assigned in a double-blind manner either creatine monohydrate (CM; 0.3 g*[kg.sup.-1]*[day.sup.-1] + 20 g Polycose) or an equivalent dose of placebo (PL) for 5 days. Blood samples were taken on days 1, 22 and 27. Consuming a LOV diet for 21 days was effective in reducing plasma creatine concentration (p < 0.01) in the LOV group. Regardless of diet, the CM group showed an increase in plasma creatine concentrations from day 22 to 27, whereas the PL group's levels remained the same (p < 0.05). Although the LOV diet caused a deprivation effect in plasma creatine concentration relative to the Omni diet, concurrent supplementation with creatine resulted in no difference in plasma creatine concentrations between the LOV and Omni diet groups. Dietary advice should be provided to LOV athletes that supplementation with creatine may help to increase their muscle stores of creatine, and thus their ATP resynthesis capabilities, to levels similar to those of omnivores. Key Words. omnivorous diet, creatine free diet, blood creatine level

Examines the effects of preceding oral creatine monohydrate supplementation with a lacto-ovo-vegetarian (LOV) diet on muscle creatine concentration. Factors that affect creatine uptake; Information on creatine; Comparison between LOV and omnivorous diet.

Consumption of a carbohydrate-electrolyte beverage during prolonged exercise has been shown to maintain plasma glucose levels in recreational and competitive athletes. In the last few years, however, alternatives such as coconut water beverages have drawn attention due to a desire for a natural beverage compared to a manufactured carbohydrate-electrolyte beverage. The purpose of this study was to examine the effects of a coconut water beverage on blood glucose during prolonged exercise. Eleven endurance trained males participated in a randomized double blind study. Each subject completed three 90-minute trials consisting of a treadmill run at 60-70% of their maximal oxygen uptake while consuming one of three beverages per trial (water, carbohydrate beverage, coconut water beverage). Every 15 minutes the subject consumed 12 ounces of the blinded beverage. Blood glucose was measured at baseline, 15 min, 30 min, 45 min, 60 min, 75 min, and 90 min of the treadmill run. There was a significant difference (p<.05) in blood glucose values between water and the coconut water beverage at 45 min, 60 min, 75 min, and 90 min time points. No significant difference was found for blood glucose values between the coconut water beverage and a carbohydrate-electrolyte beverage (p>.05). This study indicates that a natural coconut water beverage had a significant effect on blood glucose homeostasis during prolonged exercise compared to water alone. [ABSTRACT FROM AUTHOR]

Background: Adults over the age of 65 years are more prone to gastroesophageal reflux and, as such, are commonly prescribed proton pump inhibitors (PPIs). PPIs inhibit gastric acid secretion which can have adverse effects on vitamin B12 absorption. This quasi-experimental study was conducted to determine whether chronic use (≥1 year) of proton pump inhibitors (PPIs) results in decreased vitamin B12 in adults aged 68-94 years, as indicated by increased urinary methylmalonic acid (uM-MA). Methods: Fifteen men and women who had been using PPIs daily for a minimum of one year were recruited. Fifteen subjects not using PPIs were age (±3 years) and gender matched to the subjects taking PPIs. Tissue stores of vitamin B12 were determined using uM-MA. Results: The majority of subjects in this study resided in assisted care living facilities (55.66%) and the remaining subjects (43.33%) were free living. There were no significant differences in uM-MA levels between those using PPIs (Mdn = 1.1 μg uM-MA/mg creatinine), and those not using PPIs (Mdn = 1.1 μg uM-MA/mg creatinine) (p = 0.75). Conclusion: Chronic use of PPIs did not alter vitamin B12 in healthy individuals aged 68-94 years. Larger studies are indicated to validate these findings. [ABSTRACT FROM AUTHOR]