B. Marcello

Effects of a popular exercise and weight loss program on weight loss, body composition, energy expenditure and health in obese women.

ObjectiveTo determine the safety and efficacy of altering the ratio of carbohydrate and protein in low-energy diets in conjunction with a popular exercise program in obese women.DesignMatched, prospective clinical intervention study to assess efficacy of varying ratios of carbohydrate and protein intake in conjunction with a regular exercise program.ParticipantsOne-hundred sixty one sedentary, obese, pre-menopausal women (38.5 ± 8.5 yrs, 164.2 ± 6.7 cm, 94.2 ± 18.8 kg, 34.9 ± 6.4 kg·m-2, 43.8 ± 4.2%) participated in this study. Participants were weight stable and not participating in additional weight loss programs.MethodsParticipants were assigned to either a no exercise + no diet control (CON), a no diet + exercise group (ND), or one of four diet + exercise groups (presented as kcals; % carbohydrate: protein: fat): 1) a high energy, high carbohydrate, low protein diet (HED) [2,600; 55:15:30%], 2) a very low carbohydrate, high protein diet (VLCHP) [1,200 kcals; 63:7:30%], 3) a low carbohydrate, moderate protein diet (LCMP) [1,200 kcals; 50:20:30%] and 4) a high carbohydrate, low protein diet (HCLP) [1,200 kcals; 55:15:30%]. Participants in exercise groups (all but CON) performed a pneumatic resistance-based, circuit training program under supervision three times per week.MeasurementsAnthropometric, body composition, resting energy expenditure (REE), fasting blood samples and muscular fitness assessments were examined at baseline and weeks 2, 10 and 14.ResultsAll groups except CON experienced significant reductions (P < 0.05 – 0.001) in waist circumference over 14 weeks. VLCHP, LCHP and LPHC participants experienced similar but significant (P < 0.05 – 0.001) reductions in body mass when compared to other groups. Delta responses indicated that fat loss after 14 weeks was significantly greatest in VLCHP (95% CI: -5.2, -3.2 kg), LCMP (-4.0, -1.9 kg) and HCLP (-3.8, -2.1 kg) when compared to other groups. Subsequent reductions in % body fat were significantly greater in VLCHP, LCMP and HCLP participants. Initial dieting decreased (P < 0.05) relative REE similarly in all groups. All exercise groups significantly (P < 0.05) improved in muscular fitness, but these improvements were not different among groups. Favorable but non-significant mean changes occurred in lipid panels, glucose and HOMA-IR. Leptin levels decreased (P < 0.05) in all groups, except for CON, after two weeks of dieting and remained lower throughout the 14 week program. Exercise participation resulted in significant improvements in quality of life and body image.ConclusionExercise alone (ND) appears to have minimal impact on measured outcomes with positive outcomes apparent when exercise is combined with a hypoenergetic diet. Greater improvements in waist circumference and body composition occurred when carbohydrate is replaced in the diet with protein. Weight loss in all diet groups (VLCHP, LCMP and HCLP) was primarily fat and stimulated improvements in markers of cardiovascular disease risk, body composition, energy expenditure and psychosocial parameters.

Changes in weight loss, body composition and cardiovascular disease risk after altering macronutrient distributions during a regular exercise program in obese women

BackgroundThis studys purpose investigated the impact of different macronutrient distributions and varying caloric intakes along with regular exercise for metabolic and physiological changes related to weight loss.MethodsOne hundred forty-one sedentary, obese women (38.7 ± 8.0 yrs, 163.3 ± 6.9 cm, 93.2 ± 16.5 kg, 35.0 ± 6.2 kg•m-2, 44.8 ± 4.2% fat) were randomized to either no diet + no exercise control group (CON) a no diet + exercise control (ND), or one of four diet + exercise groups (high-energy diet [HED], very low carbohydrate, high protein diet [VLCHP], low carbohydrate, moderate protein diet [LCMP] and high carbohydrate, low protein [HCLP]) in addition to beginning a 3x•week-1 supervised resistance training program. After 0, 1, 10 and 14 weeks, all participants completed testing sessions which included anthropometric, body composition, energy expenditure, fasting blood samples, aerobic and muscular fitness assessments. Data were analyzed using repeated measures ANOVA with an alpha of 0.05 with LSD post-hoc analysis when appropriate.ResultsAll dieting groups exhibited adequate compliance to their prescribed diet regimen as energy and macronutrient amounts and distributions were close to prescribed amounts. Those groups that followed a diet and exercise program reported significantly greater anthropometric (waist circumference and body mass) and body composition via DXA (fat mass and % fat) changes. Caloric restriction initially reduced energy expenditure, but successfully returned to baseline values after 10 weeks of dieting and exercising. Significant fitness improvements (aerobic capacity and maximal strength) occurred in all exercising groups. No significant changes occurred in lipid panel constituents, but serum insulin and HOMA-IR values decreased in the VLCHP group. Significant reductions in serum leptin occurred in all caloric restriction + exercise groups after 14 weeks, which were unchanged in other non-diet/non-exercise groups.ConclusionsOverall and over the entire test period, all diet groups which restricted their caloric intake and exercised experienced similar responses to each other. Regular exercise and modest caloric restriction successfully promoted anthropometric and body composition improvements along with various markers of muscular fitness. Significant increases in relative energy expenditure and reductions in circulating leptin were found in response to all exercise and diet groups. Macronutrient distribution may impact circulating levels of insulin and overall ability to improve strength levels in obese women who follow regular exercise.

Effects of Zinc Magnesium Aspartate (ZMA) Supplementation on Training Adaptations and Markers of Anabolism and Catabolism.

This study examined whether supplementing the diet with a commercial supplement containing zinc magnesium aspartate (ZMA) during training affects zinc and magnesium status, anabolic and catabolic hormone profiles, and/or training adaptations. Forty-two resistance trained males (27 ± 9 yrs; 178 ± 8 cm, 85 ± 15 kg, 18.6 ± 6% body fat) were matched according to fat free mass and randomly assigned to ingest in a double blind manner either a dextrose placebo (P) or ZMA 30–60 minutes prior to going to sleep during 8-weeks of standardized resistance-training. Subjects completed testing sessions at 0, 4, and 8 weeks that included body composition assessment as determined by dual energy X-ray absorptiometry, 1-RM and muscular endurance tests on the bench and leg press, a Wingate anaerobic power test, and blood analysis to assess anabolic/catabolic status as well as markers of health. Data were analyzed using repeated measures ANOVA. Results indicated that ZMA supplementation non-significantly increased serum zinc levels by 11 – 17% (p = 0.12). However, no significant differences were observed between groups in anabolic or catabolic hormone status, body composition, 1-RM bench press and leg press, upper or lower body muscular endurance, or cycling anaerobic capacity. Results indicate that ZMA supplementation during training does not appear to enhance training adaptations in resistance trained populations.

The effects of creatine monohydrate supplementation with and without D-pinitol on resistance training adaptations.

Kerksick, CM, Wilborn, CD, Campbell, WI, Harvey, TM, Marcello, BM, Roberts, MD, Parker, AG, Byars, AG, Greenwood, LD, Almada, AL, Kreider, RB, and Greenwood, M. The effects of creatine monohydrate supplementation with and without D-pinitol on resistance training adaptations. J Strength Cond Res 23(9): 2673-2682, 2009-Coingestion of D-pinitol with creatine (CR) has been reported to enhance creatine uptake. The purpose of this study was to evaluate whether adding D-pinitol to CR affects training adaptations, body composition, whole-body creatine retention, and/or blood safety markers when compared to CR ingestion alone after 4 weeks of resistance training. Twenty-four resistance trained males were randomly assigned in a double-blind manner to creatine + pinitol (CRP) or creatine monohydrate (CR) prior to beginning a supervised 4-week resistance training program. Subjects ingested a typical loading phase (i.e., 20 g/d−1 for 5 days) before ingesting 5 g/d−1 the remaining 23 days. Performance measures were assessed at baseline (T0), week 1 (T1), and week 4 (T2) and included 1 repetition maximum (1RM) bench press (BP), 1RM leg press (LP), isokinetic knee extension, and a 30-second Wingate anaerobic capacity test. Fasting blood and body composition using dual-energy x-ray absorptiometry (DEXA) were determined at T1 and T3. Data were analyzed by repeated measures analysis of variance (ANOVA). Creatine retention increased (p < 0.001) in both groups as a result of supplementation but was not different between groups (p > 0.05). Significant improvements in upper- and lower-body strength and body composition occurred in both groups. However, significantly greater increases in lean mass and fat-free mass occurred in the CR group when compared to CRP (p <0.05). Adding D-pinitol to creatine monohydrate does not appear to facilitate further physiological adaptations while resistance training. Creatine monohydrate supplementation helps to improve strength and body composition while resistance training. Data from this study assist in determining the potential role the addition of D-pinitol to creatine may aid in facilitating training adaptations to exercise.

Poor sleep quality and insufficient sleep of a collegiate student-athlete population

OBJECTIVE Poor and inadequate sleep negatively impact cognitive and physical functioning and may also affect sports performance. The study aim is to examine sleep quality, sleep duration, and daytime sleepiness in collegiate student-athletes across a wide range of sports. DESIGN Questionnaire. SETTING University setting. PARTICIPANTS 628 athletes across 29 varsity teams at Stanford University. MEASUREMENTS Athletes completed a questionnaire inquiring about sleep quality via a modified Pittsburgh Sleep Quality Index (PSQI), sleep duration, and daytime sleepiness via Epworth Sleepiness Scale. Sleep quality on campus and while traveling for competition was rated on a 10-point scale. RESULTS Collegiate athletes were classified as poor sleepers (PSQI 5.38 ± 2.45), and 42.4% of athletes experience poor sleep quality (reporting PSQI global scores >5). Athletes reported lower sleep quality on campus than when traveling for competition (7.1 vs 7.6, P< .001). Inadequate sleep was demonstrated by 39.1% of athletes that regularly obtain <7 hours of sleep on weekdays. Fifty-one percent of athletes reported high levels of daytime sleepiness with Epworth scores ≥10. Teen student-athletes in the first and second year of college reported the highest mean levels of daytime sleepiness. Greater total sleep time was associated with daytime functioning including lower frequency of difficulty waking up for practice or class (P< .001) and lower frequency of trouble staying awake during daily activities (P< .001). CONCLUSIONS Collegiate athletes frequently experience poor sleep quality, regularly obtain insufficient sleep, and commonly exhibit daytime sleepiness.

The effects of fat-free vs. fat-containing chocolate milk ingestion on muscular strength in female collegiate softball players

Ingesting a post-workout beverage containing carbohydrate and high quality protein has been shown to favorably improve body composition and exercise performance. Chocolate milk supplies both carbohydrate and high quality proteins (casein and whey). For this reason, chocolate milk has become an increasingly popular sports nutrition beverage. To date, no one has investigated the differences between fat-free and fat-containing chocolate milk on strength performance in collegiate athletes. The purpose of this study, therefore, was to determine the effects of ingesting two forms of chocolate milk (fat free vs. fat containing) immediately after resistance exercise over an 8-week period to determine its effects on muscular strength.