The effects of supplementation with creatine and protein on muscle strength following a traditional resistance training program in middle-aged and older men.

OBJECTIVES: Creatine and protein supplementation can enhance the training outcomes of young subjects, but it is not clear if there are benefits for older individuals. Therefore, the purpose of this study was to determine the effects of creatine and protein supplementation on strength gains following a traditional resistance training program for middle-aged and older men. DESIGN, SETTING, PARTICIPANTS: This study assessed changes in strength of men aged 48-72 years following 14 weeks of resistance training supplemented with creatine and/or protein. A double-blind, randomized, placebo-controlled design placed 42 males into one of four groups: Resistance Trained Placebo (RTP, n=10); Resistance Trained Creatine (RTCr, 5g Cr, n=10); Resistance Trained Protein (RTPr, 35g whey Pr, n=11); or Resistance Trained Creatine and Protein (RTCrPr, 5g Cr and 35g Pr, n=11). INTERVENTION: All groups trained 3 days per week for 14 weeks. The resistance training program was based on progressive overload. Training loads corresponded to 80% 1 RM (one repetition maximum strength), 3 sets of 8 repetitions for the following exercises: knee extension/knee flexion; bicep curl/tricep extension; military press; lat pull down; seated leg press; and bench press. MEASUREMENTS: 1 RM for each exercise and measures of lean body mass were assessed prior to and following the 14 week program. RESULTS: Each group significantly (p < 0.05) increased strength and lean body mass, however, there were no significant group effects or group X trial interactions. CONCLUSION: Resistance training in middle-aged and older men significantly increased muscular strength and added muscle mass with no additional benefits from creatine and/or protein supplementation.

The effects of creatine and whey protein supplementation on body composition in men aged 48 to 72 years during resistance training.

OBJECTIVES: Creatine and whey protein are supplements believed to have an ergogenic effect. Very little is known regarding the effects of these dietary supplements in older men. The purpose of this study was to determine the effect of creatine and whey protein supplements, consumed independently and in combination, on total and regional body composition in middle-aged men during a resistance-training program. DESIGN, SETTING, PARTICIPANTS: Forty-two men were randomly assigned to four groups to receive supplements according to a double-blind protocol. Groups consumed their supplements three times per week immediately following their resistance training sessions. The groups were: 1) placebo (480 ml of Gatorade); 2) creatine (480 ml of Gatorade plus 5 grams of creatine); 3) whey protein (480 ml of Gatorade plus 35 grams of whey protein powder); and 4) whey protein/creatine (480 ml of Gatorade plus 5 grams of creatine and 35 grams of whey protein powder). All groups participated in resistance training 3 times per week for 14 weeks. MEASUREMENTS: At the beginning and end of the study, total and regional measures of body composition (DXA) and total (TBW), intracellular (ICW), and extracellular (ECW) body water (Multifrequency BIA) were measured and 3-day diet records were completed. RESULTS: There were significant training effects for regional arm fat (decrease), regional arm bone free-fat free mass (BF-FFM - increase), total body BF-FFM (increase), ICW (increase), and ECW (increase) but no significant group effects and only one significant group by training interaction (ECW). There were no significant changes for total calorie, carbohydrate, fat or protein intake for any of the groups from prestudy to post-study testing. CONCLUSION: The results from this study suggest that supplementation with creatine, whey protein, or a combination of creatine and whey protein, when combined with resistance training in middle-aged men, have no added benefit to changes that occur to body composition due to resistance training alone.

Effects of creatine supplementation on isometric force-time curve characteristics.

PURPOSE: To assess the effects of creatine monohydrate on isometric force-time curve parameters of sedentary college males aged 18-25 yr. METHODS: This double-blind study randomly assigned subjects to either a treatment (with creatine (Cr)) group (N = 11) or placebo group (P) (N = 8). The Cr group received 20 g x d(-1) of Cr for the first 5 d, in 5-g doses, four times daily (loading period) followed by a 5-g x d(-1) dose for the next 5 d (maintenance phase) and then no Cr ingestion for 7 d (washout period). Each 5-g dose was mixed with 250 mL of Gatorade. The P group received a placebo (cornstarch) following the exact same dosage regimen and protocol as the Cr group. All subjects were sedentary and had not used any nutritional supplements for 6 months before the study. Measurements of isometric force production of four muscle groups (elbow flexors and extensors; knee flexors and extensors) were characterized by a number of force-time parameters including strength (MF), time to maximal force (TMF), rate of force development (MRFD), and intermittent endurance (total impulse (TI) and percent force decrement (PFD)). Testing was done at pretreatment, after the 10-d loading and maintenance phases, and after the washout phase. RESULTS: Repeated measures ANOVA indicated no significant group effect for any muscle group concerning the maximal strength parameters and only two significant time effects for the knee flexors during MF and MRFD. Similarly, there were no significant group effects for any muscle group during the endurance trials; however, there was a significant time effect concerning TI for each muscle group tested. CONCLUSION: Our findings indicate that oral supplementation with creatine monohydrate in untrained males does not positively influence isometric strength but may enhance intermittent isometric muscular endurance.

Creatine supplementation during resistance training in college football athletes.

PURPOSE: This investigation assessed the effects of a 9-wk regimen of creatine monohydrate (Cr x H2O) supplementation coupled with resistance training on body composition and neuromuscular performance in NCAA Division I football athletes. METHODS: Twenty-five subjects were randomly assigned in a double-blind, randomized placebo-controlled design, to a treatment (Cr, N = 9), placebo (P, N = 8), or control group (C, N = 8). The Cr group received 20 g.d(-1) of creatine for the first 5 d in 5-g doses, four times daily, followed by 5 g.d(-1) for the remainder of the study. Each 5-g dose was mixed with 500 mL of glucose solution (Gatorade). The P group received a placebo (sodium phosphate monohydrate; NaH2PO4 x H2O) following the exact protocol as the Cr group. The C group received no supplementation. All subjects resistance trained 4 d.wk(-1). Measurements of neuromuscular performance and body composition were made pre- and post-training after supplementation while monitoring dietary intakes. RESULTS: Repeated measures ANOVA indicated significant differences occurred between the Cr group and the other two groups (P and C) for total body weight, lean body mass, cell hydration, strength, peak torque at 300 degrees.s(-1) knee flexion, percent torque decrement, and anaerobic power and capacity. However, percent body fat, peak torque during both knee flexion and extension at 60 and 180 degrees.s(-1), peak torque at 300 degrees.s(-1) during knee extension, global muscular strength (power clean), and extracellular fluid remained statistically unchanged for all groups. CONCLUSIONS: Our findings indicate that creatine, supplemented concurrently with resistance and anaerobic training, may positively affect cell hydration status and enhance performance variables further than augmentation seen with training alone.

Chromium picolinate effects on body composition and muscular performance in wrestlers.

PURPOSE: The purpose of this study was to assess the effects of 14 wk of chromium picolinate supplementation during the final 16 wk of a preseason resistance and conditioning program on body composition and neuromuscular performance in NCAA Division I wrestlers. During this phase of training, wrestlers are primarily interested in trying to improve physical performance and wrestling technique and are not engaged in severe, acute weight loss practices commonly employed before competition. METHODS: This double-blinded, randomized placebo-controlled study involved 20 wrestlers from the University of Oklahoma assigned to either a treatment group (Cr+3; N = 7; 20.4 yr +/- 0.1) receiving 200 micrograms chromium picolinate daily, a placebo group (P; N = 7; 19.9 yr +/- 0.2), or a control group (C; N = 6; 20.2 yr +/- 0.1) using a stratified random sampling technique based on weight classification. Body composition, neuromuscular performance, metabolic performance, and serum insulin and glucose were measured before and immediately following the supplementation and training period. RESULTS: Repeated measures ANOVA indicated no significant changes in body composition for any of the groups. Aerobic power increased significantly (P < 0.002) in all groups, independent of supplementation. There were significant trial and group x trial interactions for upper body endurance (P = 0.038) and relative bench press power (P = 0.050). Post-hoc analyses revealed that the C group increased upper body endurance (P = 0.006), but none of the pre- to post-test changes in bench press power were significant. CONCLUSIONS: These results suggest that chromium picolinate supplementation coupled with a typical preseason training program does not enhance body composition or performance variables beyond improvements seen with training alone.

Changes in the plantaris muscle as an indicator of alterations in lean body mass of obese Zucker rats following prolonged energy restriction and subsequent partial recovery.

To study the effects of a prolonged (80 day), severe (64% body mass loss) energy restriction and subsequent refeeding on skeletal muscle tissue, specifically the plantaris muscle, 21 genetically obese Zucker rats were selected for this study. Six rats were initially killed and served as baseline (BASE), then 15 rats underwent severe energy restriction for 80 days. Seven of these restricted rats (RESTRICT) were then killed and assessed while the other eight rats (REHAB) were fed a dry rehabilitation diet that provided 100% of the recommended energy and 1.5 times the recommended protein for growth. Once the REHAB rats had recovered approximately 45% of their original mass loss, these animals were then evaluated. Within 20 min after being killed, the plantaris muscles from each animal in each group had been removed, weighed, and frozen. Analyses included total plantaris mass, as well as differences in fiber diameters, esterase activity, and fiber type distributions between three groups (BASE, RESTRICT, and REHAB). The extreme body mass loss of 64% in genetically obese Zucker rats resulted in significant tissue weight loss and reduced fiber diameters in the plantaris muscle. Refeeding resulted in larger muscle fiber diameters that approached baseline values but an 11% difference in muscle weight remained and may be due to a decreased fiber number. Esterase activity seemed to indicate an initial fat utilization for the RESTRICT group, followed by suppressed esterase activity in the REHAB group, suggesting increased fat storage. No significant differences were found in fiber type distribution between BASE, RESTRICT, or REHAB animals.

The gynecologist and the prevention of cardiovascular disease.

This article reviews current concepts regarding the prevention of cardiovascular disease for women, with particular attention to modifiable risk factors. The background describes the magnitude of the problem, assesses the quality of the data with respect to risk factor reduction, and emphasizes several important concepts. Changes at menopause, states of endocrine aberration, and benefits and risks of hormone substitution need to be understood in conjunction with all other potentially modifiable and nonmodifiable cardiovascular risk factors. Primary care physicians have a window of opportunity to prevent this number one women's health problem. Integrating behavior modification is the key to prevention as part of the regular gynecologic visit.

The gynecologist and cardiovascular disease: a window of opportunity for prevention.

OBJECTIVE: We present current concepts and assess the quality of information available for the prevention of cardiovascular disease in women. METHODS: This article reviews research bearing on the prevention of cardiovascular disease in women, with particular attention to modifiable risk factors. We describe the magnitude of the problem and assess the quality of the data with respect to the classic risk factors. The concept is emphasized that changes at menopause, states of endocrine aberration, and benefits and risks of hormone substitution and oral contraception must be understood in conjunction with all other potentially modifiable and nonmodifiable risk factors. CONCLUSIONS: Primary care physicians, especially obstetrician/gynecologists, have a pivotal role to play in the reduction of this disease. Behavior modification is the key to integrating prevention into the regular annual visit.

Soluble fiber and serum lipids: a literature review.

Although fiber has been increasingly recognized as an important dietary constituent, controversy and confusion still exist about the physiologic effects of fiber. Specifically, the independent ability of dietary fiber to lower serum lipid levels is controversial. The purpose of this article is to review available evidence regarding the impact of soluble fibers on serum lipid levels. Soluble fibers appear to have a greater potential to alter serum lipid levels than do insoluble fibers. Significant reduction in the level of serum total cholesterol by soluble fiber was found in 68 of the 77 (88%) human studies reviewed. Of the studies measuring low-density lipoprotein cholesterol, 41 of 49 (84%) reported significant reductions. No significant changes were reported in 43 of the 57 (75%) studies that reported high-density lipoprotein cholesterol and/or in 50 of the 58 (86%) studies that measured triglyceride levels.

Matriarchal model for cardiovascular prevention.

Family patterns of cardiovascular risk behavior are well documented. Significant correlation exists between spouse-spouse, parent-child, and sibling-sibling for cholesterol, high- and low-density lipoprotein, diet, physical activity, and smoking. Family/environmental influences are important in how/if risk and/or preventive behavior is learned. The family matriarch commonly functions as gatekeeper, controlling eating behavior, access to health care, and other patterns. She often acts as menu planner, shopper, and preparer of meals for all family members. She provides information and verbal reinforcement about food and is a powerful model concerning dietary practices. In fact, the mother, as head of household in most single-parent families, may be the only adult model for many children. Because relevance and credibility are the most important characteristics of a behavioral model, parents (especially mothers) are strong models for observational learning by children. Risk factor information and risk reduction activities adopted by the matriarch can be generalized to the entire family if she learns the skills to act as a change agent. Initiation of this process of education and training the matriarch lies with primary care providers for women (Ob-Gyns see most women). By teaching risk reduction to the matriarch as a component of primary care, physician interaction can have a rippling effect.

Long-term therapy with cyclosporin A does not influence serum concentrations of vitamin D metabolites in patients with multiple sclerosis.

Animal studies have shown that cyclosporin A (CyA) stimulates renal 25-hydroxyvitamin D3 [25(OH)D3]-1 alpha-hydroxylase activity; in contrast, studies in renal transplant recipients indirectly suggest that CyA reduces 1 alpha,25-dihydroxyvitamin D3 [1,25(OH)2D3] production. To clarify the effect of CyA on vitamin D metabolite concentrations, we measured parameters of calcium metabolism in 37 CyA-treated patients (median trough whole blood levels 171-222 ng/ml) with multiple sclerosis and initially normal kidney function. The patients participated in a randomized double-blind study to assess the efficacy of CyA in multiple sclerosis. An age- and sex-matched control group (n = 39) received azathioprine (Aza). Measurements were made at the end of a 2-year treatment period. The 1,25(OH)2D3 serum concentrations were not significantly different between the two groups, although they were numerically lower in CyA-treated patients [median (range), 28.4 pg/ml (7.8-85.9) vs 41.0 pg/ml (9.2-105.1) in Aza-treated patients]. The 25(OH)D3 levels were comparable in both groups. There was no correlation between the 25(OH)D3 and 1,25(OH)2D3 concentrations. The renal function in both groups was stable in the last 6 months of the study. At the end of the study period, the endogenous creatinine clearance was significantly lower in the CyA-treated group (85 +/- 17 ml/min versus 99 +/- 22 in the Aza-treated group, P less than 0.05). The carboxyterminal parathyroid hormone (C-PTH) was within the normal range in both groups, although CyA-treated patients had significantly higher concentrations (P less than 0.01). The urinary excretion of mineral ions, cations and protein was similar in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Macronutrient intake and utilization by rats: interactions with type I adrenocorticoid receptor stimulation.

Corticosterone-free (adrenalectomized, ADX) and intact rats were offered experimentally compounded diets in which 65% of available calories were supplied by a single macronutrient (single-diet study). ADX impaired the intake, weight gain (especially as body fat), and efficient utilization of high-protein and high-fat diets. In contrast, no behavioral, metabolic, or compositional changes could be found among ADX rats maintained on a diet high in carbohydrates. When ADX rats were given separate sources of macronutrients (self-selection study) they did not self-select a high-carbohydrate diet. Instead, they displayed a strong fat avoidance and a relative increase in protein intake, the macronutrient they utilize least efficiently. Separate groups of ADX animals were continuously infused with 25 or 125 micrograms.kg-1.day-1 aldosterone, a specific type I adrenocorticoid receptor agonist. Type I receptor stimulation eliminated all ADX-related deficiencies found in the single-diet and self-selection studies: caloric intake, feeding efficiency, carcass composition, and macronutrient preferences were restored to or beyond the corresponding values of adrenal-intact rats. The normal rat's ability to ingest and utilize macronutrients optimally is dependent on corticosterone's stimulation of type I receptors.

Acute, chronic, and interactive effects of type I and II corticosteroid receptor stimulation on feeding and weight gain.

Type I (aldosterone) and/or type II (dexamethasone or RU28362) corticosterone receptor agonists were continuously infused in adrenalectomized Sprague-Dawley rats for 28 days at doses of 3.4, 17.2, or 86.2 nmol/day. Additional groups received combined agonist infusions, blank infusions, or sham operations. The type I agonist stimulated body weight gain, and the type II agonists were both suppressive, differing mainly in degree. Although there were a few early effects of these hormones (usually a stage of exaggerated activity), once passed, chronic stimulation was marked by steady or slightly increasing steroid influence on body weight. Throughout the chronic phase of this study there was no departure from a simple opponent model of type I and II ligand actions, and their combination approximated an arithmetic summation of the two separate agonists. This was generally true of feeding as well, although steroid effects on intake were always less pronounced. In contrast to chronic administration, acute combinations of these agonists were highly interactive, producing slight losses than large gains for the aldosterone and RU28362 combinations, but a large gain then small loss for the aldosterone and dexamethasone combination. These results imply that RU28362 and dexamethasone differ in more respects than potency. Because normal endogenous type II stimulation is acute and occurs against a background of type I receptor occupation, mixed agonist interactions are probably the rule for everyday physiological activity, not the exception.

Corticosterone's dual metabolic actions.

Corticosterone possesses two distinctly opposite metabolic actions. The actions are strictly dose-dependent and are linked to type I and type II corticosteroid receptor binding. These conclusions are drawn from continuous infusion studies where corticosterone yields a bitonic dose-response curve for body weight gain and feeding efficiency. Anabolic at low serum levels, corticosterone concentrations above 2 micrograms/dl bring about an opponent catabolic process that intensifies and eventually masks the anabolic action. Relatively pure type I (aldosterone) and type II (RU28362 and dexamethasone) corticosterone receptor agonists produce opposite monotonic functions that respectively mimic the ascending and descending arms of the corticosterone dose-response curve. Stimulation of either receptor increases the proportion of carcass fat to lean body mass by either increasing carcass lipids (type I) or by reducing protein (type II).

Aldosterone and the mobilization of energy.

Aldosterone diminishes the ability to endure starvation. Its exogenous administration to adrenalectomized rats advances the onset of hypothermia and death. The impairment seems to lie in an inability to mobilize energy stores fully: animals given the steroid are unable to lose weight at a normal rate. The findings help to establish the significance of mineralocorticoids in the regulation of energy exchange and solve some theoretical questions as to their general mode of action.

Environmental control of energy metabolism in rats.

Food availability was arranged so that episodes of feeding were separated by long periods of deprivation. Distinctly different contexts were associated with each condition. For other animals, relatively short periods of deprivation stood in contrast to relatively long opportunities to free-feed, and were also embedded in widely differing physical contexts. These temporal relationships among the conditions were adjusted to sharpen the saliency of each metabolic condition and thereby enhance its associability with the distinctive environment in which each occurred. To avoid the possibility of circadian entrainment, the feeding or deprivation episodes occurred at unpredictable times according to a variable-time schedule. Following several training cycles and an extended period of free-feeding in a neutral environment, the animals were reexposed to the various contexts and sacrificed for metabolite assays. The environment predictive of feeding elevated adipocyte lipoprotein lipase activity and lowered the levels of serum free fatty acids. The deprivation context boosted serum triglycerides and blood urea nitrogen. The conditioned responses were all of a compensatory nature: Feeding cues resulted in accelerated caloric deposition, deprivation cues elicited conditioned mobilization of stored energy. While protein catabolism and several indices of fat metabolism appear to be conditionable, no evidence of environmental control of glycemic responses was observed.

Primary germinoma of the brain. Immunocytochemical demonstration of tumour cells in the cerebrospinal fluid.

A patient is presented, who developed a suprasellar tumour. Stereotactical biopsy of the tumour revealed the diagnosis of a dysgerminoma. Immunocytochemical examination of the CSF showed neoplastic cells staining for human chorionic gonadotropin and for alpha-fetoprotein. The authors stress the possibility to diagnose primary intracranial germ cell tumours without operation.

Effects of fructose feeding on lipid parameters in obese and lean, diabetic and nondiabetic Zucker rats.

Effects of fructose feeding in moderate amounts on lipid metabolism of obese versus lean, and diabetic versus nondiabetic Zucker rats, were studied. Forty pairs of male lean and obese animals were assigned to two dietary groups, fructose and glucose. For each diet, one-half of lean and obese animals were injected with streptozotocin intraperitoneally (i.p.) to induce diabetes, and the other half were injected with buffer i.p. as a nondiabetic control group. After 9 wk of feeding, animals were fasted overnight, decapitated and exsanguinated. Organs were removed and weighed. Blood glucose, insulin, lactic acid, triglycerides, cholesterol, total liver lipids and urinary glucose were determined. Hyperphagia was observed in obese, non-diabetic and lean-diabetic animals. Streptozotocin injection drastically reduced insulin levels, and produced an impairment of growth, hyperglycemia, glucosuria, polydipsia and polyuria. Fructose feeding increased organ weights in kidney, liver and retroperitoneal adipose tissue, regardless of diabetic state. However, lactic acid levels were lower in fructose-fed groups than glucose-fed groups. In obese rats serum triglyceride levels were also lower in fructose-fed groups than in glucose-fed groups. Serum cholesterol was not affected by fructose feeding. The results indicated that fructose feeding did not produce hyperlipemia and lactic acidosis in the blood circulation in Zucker rats. However, fructose feeding did not improve glucose intolerance in diabetic animals, rather fructose feeding produced hyperinsulinemia in nondiabetic, obese animals.