Jonathan Oliver

A Structured Diet and Exercise Program Promotes Favorable Changes in Weight Loss, Body Composition, and Weight Maintenance

BACKGROUNDnA number of diet and exercise programs purport to help promote and maintain weight loss. However, few studies have compared the efficacy of different methods.nnnOBJECTIVEnTo determine whether adherence to a meal-replacement-based diet program (MRP) with encouragement to increase physical activity is as effective as following a more structured meal-plan-based diet and supervised exercise program (SDE) in sedentary obese women.nnnDESIGNnRandomized comparative effectiveness trial.nnnPARTICIPANTS/SETTINGnFrom July 2007 to October 2008, 90 obese and apparently healthy women completed a 10-week university-based weight loss trial while 77 women from this cohort also completed a 24-week weight maintenance phase.nnnINTERVENTIONnParticipants were matched and randomized to participate in an MRP or SDE program.nnnMAIN OUTCOME MEASURESnWeight loss, health, and fitness-related data were assessed at 0 and 10 weeks on all subjects as well as at 14, 22, and 34 weeks on participants who completed the weight maintenance phase.nnnSTATISTICAL ANALYSES PERFORMEDnData were analyzed by multivariate analysis of variance for repeated measures.nnnRESULTSnDuring the 10-week weight loss phase, moderate and vigorous physical activity levels were significantly higher in the SDE group with no differences observed between groups in daily energy intake. The SDE group lost more weight (-3.1 ± 3.7 vs -1.6 ± 2.5 kg; P = 0.03); fat mass (-2.3 ± 3.5 vs -0.9 ± 1.6 kg; P = 0.02); centimeters from the hips (-4.6 ± 7 vs -0.2 ± 6 cm; P = 0.002) and waist (-2.9 ± 6 vs -0.6 ± 5 cm; P = 0.05); and, experienced a greater increase in peak aerobic capacity than participants in the MRP group. During the 24-week maintenance phase, participants in the SDE group maintained greater moderate and vigorous physical activity levels, weight loss, fat loss, and saw greater improvement in maximal aerobic capacity and strength.nnnCONCLUSIONSnIn sedentary and obese women, an SDE-based program appears to be more efficacious in promoting and maintaining weight loss and improvements in markers of health and fitness compared to an MRP type program with encouragement to increase physical activity.

A Carbohydrate-Restricted Diet during Resistance Training Promotes More Favorable Changes in Body Composition and Markers of Health in Obese Women with and without Insulin Resistance

Abstract Objective: To determine whether sedentary obese women with elevated levels of homeostatic model assessment (HOMA) insulin resistance (ie, > 3.5) experience greater benefits from an exercise + higher-carbohydrate (HC) or carbohydrate-restricted weight loss program than women with lower HOMA levels. Methods: 221 women (age, 46.5 ± 12 years; body weight, 90.3 ± 16 kg; body mass index, 33.8 ± 5 kg/m2) participated in a 10-week supervised exercise and weight loss program. The fitness program involved 30 minutes of circuit-style resistance training 3 days per week. Subjects were prescribed low-fat (30%) isoenergetic diets that consisted of 1200 kcals per day for 1 week (phase 1) and 1600 kcals per day for 9 weeks (phase 2) with HC or higher protein (HP). Fasting blood samples, body composition, anthropometry, resting energy expenditure, and fitness measurements were obtained at 0 and 10 weeks. Subjects were retrospectively stratified into lower (LH) or higher (HH) than 3.5 HOMA groups. Data were analyzed by multivariate analysis of variance with repeated measures and are presented as mean ± standard deviation changes from baseline. Results: Baseline HOMA levels in the LH group were significantly lower than those in the HH group (LH, 0.6 ± 0.7; HH, 6.3 ± 3.4; P = 0.001). Diet and training significantly decreased body weight (−3.5 ± 3 kg), fat mass (−2.7 ± 3 kg), blood glucose (−3%), total cholesterol (−4.5%), low-density lipoproteins (−5%), triglycerides (−5.9%), systolic blood pressure (−2.6%), and waist circumference (−3.7%), while increasing peak aerobic capacity (7.3%). Subjects in the HP group experienced greater weight loss (−4.4 ± 3.6 kg vs −2.6 ± 2.9 kg), fat loss (−3.4 ± 2.7 kg vs −1.7 ± 2.0 kg), reductions in serum glucose (3% vs 2%), and decreases in serum leptin levels (−30.8% vs −10.8%) than those in the HC group. Participants in the HH (−14.1%) and HP-HH (−21.6%) groups observed the greatest reduction in serum blood glucose. Conclusion: A carbohydrate-restricted diet promoted more favorable changes in weight loss, fat loss, and markers of health in obese women who initiated an exercise program compared with a diet higher in carbohydrate. Additionally, obese women who initiated training and dieting with higher HOMA levels experienced greater reductions in blood glucose following an HP diet.

A buffered form of creatine does not promote greater changes in muscle creatine content, body composition, or training adaptations than creatine monohydrate

BackgroundCreatine monohydrate (CrM) has been consistently reported to increase muscle creatine content and improve high-intensity exercise capacity. However, a number of different forms of creatine have been purported to be more efficacious than CrM. The purpose of this study was to determine if a buffered creatine monohydrate (KA) that has been purported to promote greater creatine retention and training adaptations with fewer side effects at lower doses is more efficacious than CrM supplementation in resistance-trained individuals.MethodsIn a double-blind manner, 36 resistance-trained participants (20.2u2009±u20092u2009years, 181u2009±u20097u2009cm, 82.1u2009±u200912u2009kg, and 14.7u2009±u20095% body fat) were randomly assigned to supplement their diet with CrM (Creapure® AlzChem AG, Trostberg, Germany) at normal loading (4 x 5u2009g/d for 7-days) and maintenance (5u2009g/d for 21-days) doses; KA (Kre-Alkalyn®, All American Pharmaceutical, Billings, MT, USA) at manufacturer’s recommended doses (KA-L, 1.5u2009g/d for 28-days); or, KA with equivalent loading (4 x 5u2009g/d for 7-days) and maintenance (5u2009g/d) doses of CrM (KA-H). Participants were asked to maintain their current training programs and record all workouts. Muscle biopsies from the vastus lateralis, fasting blood samples, body weight, DEXA determined body composition, and Wingate Anaerobic Capacity (WAC) tests were performed at 0, 7, and 28-days while 1RM strength tests were performed at 0 and 28-days. Data were analyzed by a repeated measures multivariate analysis of variance (MANOVA) and are presented as meanu2009±u2009SD changes from baseline after 7 and 28-days, respectively.ResultsMuscle free creatine content obtained in a subgroup of 25 participants increased in all groups over time (1.4u2009±u200920.7 and 11.9u2009±u200924.0u2009mmol/kg DW, pu2009=u20090.03) after 7 and 28-days, respectively, with no significant differences among groups (KA-L −7.9u2009±u200922.3, 4.7u2009±u200927.0; KA-H 1.0u2009±u200912.8, 9.1u2009±u200923.2; CrM 11.3u2009±u200923.9, 22.3u2009±u200921.0u2009mmol/kg DW, pu2009=u20090.46). However, while no overall group differences were observed (pu2009=u20090.14), pairwise comparison between the KA-L and CrM groups revealed that changes in muscle creatine content tended to be greater in the CrM group (KA-L −1.1u2009±u20094.3, CrM 11.2u2009±u20094.3u2009mmol/kg DW, pu2009=u20090.053 [meanu2009±u2009SEM]). Although some significant time effects were observed, no significant group x time interactions (pu2009>u20090.05) were observed in changes in body mass, fat free mass, fat mass, percent body fat, or total body water; bench press and leg press 1RM strength; WAC mean power, peak power, or total work; serum blood lipids, markers of catabolism and bone status, and serum electrolyte status; or, whole blood makers of lymphocytes and red cells. Serum creatinine levels increased in all groups (pu2009<u20090.001) with higher doses of creatine promoting greater increases in serum creatinine (pu2009=u20090.03) but the increases observed (0.1 – 0.2u2009mg/dl) were well within normal values for active individuals (i.e., <1.28u2009±u20090.2u2009mg/dl). Serum LDL was decreased to a greater degree following ingesting loading doses in the CrM group but returned to baseline during the maintenance phase. No side effects were reported.ConclusionsNeither manufacturers recommended doses of KA (1.5u2009g/d) or KA with equivalent loading (20u2009g/d for 7-days) and maintenance doses (5u2009g/d for 21-days) of CrM promoted greater changes in muscle creatine content, body composition, strength, or anaerobic capacity than CrM (20u2009g/d for 7-days, 5u2009g/d for 21-days). There was no evidence that supplementing the diet with a buffered form of creatine resulted in fewer side effects than CrM. These findings do not support claims that consuming a buffered form of creatine is a more efficacious and/or safer form of creatine to consume than creatine monohydrate.

Comparative effectiveness of two popular weight loss programs in women II: metabolic markers

Background A number of commercial diet and exercise programs are promoted to help people lose weight and improve fitness. However, few studies have compared the effects of following different types of exercise and diet interventions on weight loss. The purpose of this study was to compare the efficacy of a more structured meal plan based diet intervention and supervised exercise program that included resistance-exercise to a traditional point based diet program with weekly counseling and encouragement to exercise. Methods Fifty-one sedentary women (35±8 yrs, 163±7 cm; 90±14 kg; 47±7% body fat, 34±5 kg/m 2 ) were randomized to participate in the Curves (C) or Weight Watchers (W) weight loss programs for 16-weeks. Participants in the C program were instructed to follow a 1,200 kcal/d diet for 1-week, 1,500 kcal/d diet for 3-weeks, and 2,000 kcals/d diet for 2-weeks, consisting of 30% carbohydrate, 45% protein, and 30% fat. Subjects repeated this diet for the 16-week period. Subjects also participated in the Curves circuit style resistance training program 3-days/week and were encouraged to walk at a brisk pace for 30-minutes on non-training days. This program involved performing 30-60 seconds of bi-directional hydraulic-based resistance exercise on 13 machines interspersed with 30-60 seconds of low-impact callisthenic or Zumba dance exercise. Participants in the W group followed the W pointbased diet program, received weekly counseling at a local W facility, and were encouraged to increase physical activity. Fasting blood samples were obtained at 0, 4, 10, & 16 weeks and analyzed by multivariate analysis of variance (MANOVA) with repeated measures for changes in triglycerides (TG), total cholesterol (CHL), low density lipoprotein cholesterol (LDL-c), high density lipoprotein cholesterol (HDL-c), the CHL:HDL-C ratio, and blood glucose. Data are presented as percent changes from baseline for the C and W groups, respectively, after 4, 10, and 16 weeks. Results

The effects of IQPLUS Focus on cognitive function, mood and endocrine response before and following acute exercise

BackgroundPhosphatidylserine (PS) is a phospholipid found in cell membranes of most animals and plants. PS has been shown to reduce stress and increase performance in runners, cyclists and golfers. The purpose of this study was to investigate the effects of a PS containing formulation on cognitive function, mood and endocrine response before and after intense resistance exercise.Methods18 lower body, resistance trained, college aged males ingested 14 days of supplement (IQPLUS Focus, providing 400 mg of soy-derived PS) and a Placebo (PL), in a randomized, double-blind, placebo controlled, cross-over manner. Following 14 days of supplementation, participants performed an acute bout of lower body resistance training. Mood (Profile of Mood States, POMS) and cognitive function (Serial Subtraction Test, SST) were measured prior to, 5 minutes after, and 60 minutes after exercise. Venous blood samples were collected prior to, and 5, 15, 25, 40 and 60 minutes after exercise. Blood samples were analyzed for plasma cortisol and testosterone. Data were analyzed using repeated measures ANOVA.ResultsPS supplementation significantly reduced the time needed for a correct calculation on the SST by 20% (reduced by 1.27 s per calculation; PL: 6.4 s, PS: 5.13 s; p = 0.001), and reduced the total amount of errors by 39% (PL: 1.28 + .69, PS: .78 + .27, p = 0.53), and increased the amount of correct calculations by 13% (PL: 22.1 + 2.24, PS: 24.9 + 1.52, p = 0.07) prior to or in response to exercise compared to PL. Following exercise, there was no difference in SST scores between PS and PL. There were no significant changes in regards to mood or endocrine response to exercise as a result of PS supplementation.ConclusionPS supplementation significantly increased cognitive function prior to exercise. Improved cognitive function could benefit athletes and non-athletes alike. PS did not appear to affect mood or endocrine response prior to or following resistance exercise.

Comparative effectiveness of two popular weight loss programs in women III: health and fitness markers

Background A number of commercial diet and exercise programs are promoted to help people lose weight and improve fitness. However, few studies have compared the effects of following different types of exercise and diet interventions on weight loss and/or changes in health and fitness markers. The purpose of this study was to compare the efficacy of a more structured meal plan based diet intervention and supervised exercise program that included resistance-exercise to a traditional point based diet program with weekly counseling and encouragement to increase physical activity.

Greater Strength Drives Difference in Power between Sexes in the Conventional Deadlift Exercise

Limited research exists comparing sex differences in muscular power. The primary purpose of this research was to determine if differences exist in power and velocity in the conventional deadlift (CDL). A secondary purpose was to examine the relationship among power, velocity, strength, and fat free mass (FFM). Eighteen strength trained athletes with ≥1 year CDL experience (women: n = 9, 29 ± 2 years, 162.3 ± 1.8 cm, 62 ± 2.4 kg, 23.3 ± 3.2 % body fat (%BF); men: n = 9, 29 ± 3 years, 175.6 ± 1.8 cm, 85.5 ± 1.4 kg, 14.8 ± 2.4 %BF), and ≥1.5 one repetition maximum (1-RM) CDL: body mass (BM) ratio (women: 1.6 ± 0.1 1-RM CDL: BM; men: 2.3 ± 0.1 1-RM CDL: BM), performed baseline (body composition, 1-RM CDL) and experimental sessions, in which velocity and power were measured at 30%, 60%, and 90% 1-RM. Repeated measures ANOVA and bivariate correlations were conducted. Men produced higher absolute average and peak power across all loads, but higher average velocity at only 30% 1-RM. When normalized to FFM, men produced higher peak and average power; however, women produced higher peak and average velocities across all loads. FFM and 1-RM were correlated with power. Greater power observed in men is driven by larger muscle mass, which contributes to greater strength.

Experiencing the impact of weight loss on work capacity prior to initiation of a weight loss program enhances success

Background A number of psychological interventions have been employed prior to and/or during exercise and weight loss interventions in an attempt to influence exercise adherence, compliance, and/or success. However, few studies have evaluated whether these types of efforts influence program efficacy. The purpose of this study was to determine whether having sedentary and overweight individuals experience the impact of losing weight on work capacity prior to initiation of an exercise and/or weight loss program would influence weight loss success.

Comparative effectiveness of two popular weight loss programs in women I: body composition and resting energy expenditure

Background A number of commercial diet and exercise programs are promoted to help people lose weight and improve fitness. However, few studies have compared the effects of following different types of exercise and diet interventions on weight loss. The purpose of this study was to compare the efficacy of a more structured meal plan based diet intervention and supervised exercise program to a traditional point based diet program with weekly counseling and encouragement to exercise.

Analysis of efficacy and cost effectiveness of popular weight loss and fitness programs

Background Obesity is associated with many negative health outcomes. Diet and exercise has been shown to reduce obesity and various other factors linked to poor health. One of the major concerns is the expense of diet and exercise programs. This study compared the cost effectiveness of four popular weight loss programs and controls in terms of weight loss success and outcomes. Methods