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<title>FitMarker</title>
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<description>Stories posted in Research</description>
<language>en-us</language>
<pubDate>Mon, 21 May 2012 15:13:52 -0500</pubDate>
<item>
<title>Differential effects of strength training leading to failure versus not to failure on hormonal responses, strength, and muscle         power gains</title>
<link>http://fitmarker.com/weight-training/differential-effects-of-strength-training-leading-to-failure-versus-not-to-failure-on-hormonal-responses-strength-and-muscle-power-gains/</link>
<description><![CDATA[ The purpose of this study was to examine the efficacy of 11 wk of resistance training to failure vs. nonfailure, followed by an identical 5-wk peaking period of maximal strength and power training for both groups as well as to examine the underlying physiological changes in basal circulating anabolic and catabolic hormones. Forty-two physically active men were matched and then randomly assigned to either a training to failure (RF; n = 14), nonfailure (NRF; n = 15), or control groups (C; n = 13). Muscular and power testing and blood draws to determine basal hormonal concentrations were conducted before the initiation of training (T0), after 6 wk of training (T1), after 11 wk of training (T2), and after 16 wk of training (T3). Both RF and NRF resulted in similar gains in 1-repetition maximum bench press (23 and 23%) and parallel squat (22 and 23%), muscle power output of the arm (27 and 28%) and leg extensor muscles (26 and 29%), and maximal number of repetitions performed during parallel squat (66 and 69%). RF group experienced larger gains in the maximal number of repetitions performed during the bench press. The peaking phase (T2 to T3) after NRF resulted in larger gains in muscle power output of the lower extremities, whereas after RF it resulted in larger gains in the maximal number of repetitions performed during the bench press. Strength training leading to RF resulted in reductions in resting concentrations of IGF-1 and elevations in IGFBP-3, whereas NRF resulted in reduced resting cortisol concentrations and an elevation in resting serum total testosterone concentration. This investigation demonstrated a potential beneficial stimulus of NRF for improving strength and power, especially during the subsequent peaking training period, whereas performing sets to failure resulted in greater gains in local muscular endurance. Elevation in IGFBP-3 after resistance training may have been compensatory to accommodate the reduction in IGF-1 to preserve IGF availability. ]]></description>
<pubDate>Mon, 14 May 2012 01:53:53 -0500</pubDate>
<guid>http://fitmarker.com/weight-training/differential-effects-of-strength-training-leading-to-failure-versus-not-to-failure-on-hormonal-responses-strength-and-muscle-power-gains/</guid>
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<title>effects on mixed muscle protein synthesis at rest and following resistance exercise in young men</title>
<link>http://fitmarker.com/supplementation/effects-on-mixed-muscle-protein-synthesis-at-rest-and-following-resistance-exercise-in-young-men/</link>
<description><![CDATA[ This study was designed to compare the acute response of mixed muscle protein synthesis (MPS) to rapidly (i.e., whey hydrolysate and soy) and slowly (i.e., micellar casein) digested proteins both at rest and after resistance exercise. Three groups of healthy young men (n = 6 per group) performed a bout of unilateral leg resistance exercise followed by the consumption of a drink containing an equivalent content of essential amino acids (10 g) as either whey hydrolysate, micellar casein, or soy protein isolate. Mixed MPS was determined by a primed constant infusion of L-[ring-13C6]phenylalanine. Ingestion of whey protein resulted in a larger increase in blood essential amino acid, branched-chain amino acid, and leucine concentrations than either casein or soy (P &amp;lt; 0.05). Mixed MPS at rest (determined in the nonexercised leg) was higher with ingestion of faster proteins (whey = 0.091 ± 0.015, soy = 0.078 ± 0.014, casein = 0.047 ± 0.008%/h); MPS after consumption of whey was ∼93% greater than casein (P &amp;lt; 0.01) and ∼18% greater than soy (P = 0.067). A similar result was observed after exercise (whey &amp;gt; soy &amp;gt; casein); MPS following whey consumption was ∼122% greater than casein (P &amp;lt; 0.01) and 31% greater than soy (P &amp;lt; 0.05). MPS was also greater with soy consumption at rest (64%) and following resistance exercise (69%) compared with casein (both P &amp;lt; 0.01). We conclude that the feeding-induced simulation of MPS in young men is greater after whey hydrolysate or soy protein consumption than casein both at rest and after resistance exercise; moreover, despite both being fast proteins, whey hydrolysate stimulated MPS to a greater degree than soy after resistance exercise. These differences may be related to how quickly the proteins are digested (i.e., fast vs. slow) or possibly to small differences in leucine content of each protein. ]]></description>
<pubDate>Sat, 12 May 2012 18:59:00 -0500</pubDate>
<guid>http://fitmarker.com/supplementation/effects-on-mixed-muscle-protein-synthesis-at-rest-and-following-resistance-exercise-in-young-men/</guid>
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<title>The acute effects of the thermogenic supplement Meltdown on energy expenditure, fat oxidation, and hemodynamic responses in young, healthy males</title>
<link>http://fitmarker.com/supplementation/the-acute-effects-of-the-thermogenic-supplement-meltdown-on-energy-expenditure-fat-oxidation-and-hemodynamic-responses-in-young-healthy-males/</link>
<description><![CDATA[ <b>Results:</b>
Hemodynamic variables (HR and BP) were not significantly affected prior to exercise with either supplement (p &amp;gt; 0.05) and the expected exercise-induced increases observed in HR and BP that decreased into recovery were not different between supplements (p &amp;gt; 0.05). Relative to any supplement-induced differences in exercise performance, VO2max assessed at each of the testing sessions demonstrated no significant differences between Meltdown and placebo (45.31 ± 6.10 vs. 41.69 ± 9.98 ml O2/kg/min, p = 0.185).
Meltdown increased REE significantly more than placebo at 45 min (1.44 ± 0.25 vs. 1.28 ± 0.23 kcal/min; p = 0.003) and 60 min (1.49 ± 0.28 vs. 1.30 ± 0.22 kcal/min; p = 0.025) post-ingestion. Furthermore, REE 60 min post-exercise (120 min following supplement administration) was significantly higher in the Meltdown group (1.51 ± 0.26 vs. 1.33 ± 0.27 kcals/min; p = 0.014) (Figure ​(Figure1).1). Over the course of the evaluation period, AUC analysis demonstrated that REE was significantly increased with Meltdown compared to placebo (992.5 ± 133.1 vs. 895.1 ± 296.1 kcals; p = 0.043) (Figure ​(Figure22). ]]></description>
<pubDate>Thu, 10 May 2012 03:46:11 -0500</pubDate>
<guid>http://fitmarker.com/supplementation/the-acute-effects-of-the-thermogenic-supplement-meltdown-on-energy-expenditure-fat-oxidation-and-hemodynamic-responses-in-young-healthy-males/</guid>
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<title>beta-Alanine supplementation augments muscle carnosine content and attenuates fatigue during repeated isokinetic contraction bouts in trained sprinters.</title>
<link>http://fitmarker.com/supplementation/beta-alanine-supplementation-augments-muscle-carnosine-content-and-attenuates-fatigue-during-repeated-isokinetic-contraction-bouts-in-trained-sprinters/</link>
<description><![CDATA[ Abstract
Carnosine (beta-alanyl-l-histidine) is present in high concentrations in human skeletal muscle. The ingestion of beta-alanine, the rate-limiting precursor of carnosine, has been shown to elevate the muscle carnosine content. We aimed to investigate, using proton magnetic resonance spectroscopy (proton MRS), whether oral supplementation with beta-alanine during 4 wk would elevate the calf muscle carnosine content and affect exercise performance in 400-m sprint-trained competitive athletes. Fifteen male athletes participated in a placebo-controlled, double-blind study and were supplemented orally for 4 wk with either 4.8 g/day beta-alanine or placebo. Muscle carnosine concentration was quantified in soleus and gastrocnemius by proton MRS. Performance was evaluated by isokinetic testing during five bouts of 30 maximal voluntary knee extensions, by endurance during isometric contraction at 45% maximal voluntary contraction, and by the indoor 400-m running time. beta-Alanine supplementation significantly increased the carnosine content in both the soleus (+47%) and gastrocnemius (+37%). In placebo, carnosine remained stable in soleus, while a small and significant increase of +16% occurred in gastrocnemius. Dynamic knee extension torque during the fourth and fifth bout was significantly improved with beta-alanine but not with placebo. Isometric endurance and 400-m race time were not affected by treatment. In conclusion, 1) proton MRS can be used to noninvasively quantify human muscle carnosine content; 2) muscle carnosine is increased by oral beta-alanine supplementation in sprint-trained athletes; 3) carnosine loading slightly but significantly attenuated fatigue in repeated bouts of exhaustive dynamic contractions; and 4) the increase in muscle carnosine did not improve isometric endurance or 400-m race time. ]]></description>
<pubDate>Wed, 09 May 2012 14:34:08 -0500</pubDate>
<guid>http://fitmarker.com/supplementation/beta-alanine-supplementation-augments-muscle-carnosine-content-and-attenuates-fatigue-during-repeated-isokinetic-contraction-bouts-in-trained-sprinters/</guid>
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<title>Protein Ingestion Prior To Sleep Improves Post-Exercise Overnight Recovery.</title>
<link>http://fitmarker.com/supplementation/protein-ingestion-prior-to-sleep-improves-post-exercise-overnight-recovery/</link>
<description><![CDATA[ The role of nutrition in modulating post-exercise overnight recovery remains to be elucidated. We assessed the impact of protein ingestion immediately prior to sleep on digestion and absorption kinetics and protein metabolism during overnight recovery from a single bout of resistance type exercise.
METHODS:
16 healthy young males performed a single bout of resistance type exercise in the evening (20:00) after a full day of dietary standardization. All subjects were provided with appropriate recovery nutrition (20 g protein, 60 g carbohydrate) immediately after exercise (21:00). Thereafter, 30 min prior to sleep (23:30 h) subjects ingested a beverage with (PRO) or without (PLA) 40 g specifically produced intrinsically [1-C]phenylalanine labeled casein protein. Continuous intravenous infusions with [ring-H5]phenylalanine and [ring-H2]tyrosine were applied with blood and muscle samples collected to assess protein digestion and absorption kinetics, whole-body protein balance and mixed muscle protein synthesis rates throughout the night (7.5 h).
RESULTS:
During sleep casein protein was effectively digested and absorbed resulting in a rapid rise in circulating amino acid levels which were sustained throughout the remainder of the night. Protein ingestion prior to sleep increased whole-body protein synthesis rates (311±8 vs 246±9 ∼mol·kg·7.5 h ) and improved net protein balance (61±5 vs -11±6 μmol·kg·7.5 h ) in the PRO vs PLA experiment, respectively; P&amp;lt;0.01). Mixed muscle protein synthesis rates were ∼22% higher in the PRO vs PLA experiment, which reached borderline significance (0.059±0.005 vs 0.048±0.004 %·h; P=0.05).
CONCLUSION:
This is the first study to show that protein ingested immediately prior to sleep is effectively digested and absorbed, thereby stimulating muscle protein synthesis and improving whole-body protein balance during post-exercise, overnight recovery. ]]></description>
<pubDate>Wed, 09 May 2012 04:15:13 -0500</pubDate>
<guid>http://fitmarker.com/supplementation/protein-ingestion-prior-to-sleep-improves-post-exercise-overnight-recovery/</guid>
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<item>
<title>Placebos Are Getting More Effective. Drugmakers Are Desperate to Know Why.</title>
<link>http://fitmarker.com/supplementation/placebos-are-getting-more-effective-drugmakers-are-desperate-to-know-why/</link>
<description><![CDATA[ Merck was in trouble. In 2002, the pharmaceutical giant was falling behind its rivals in sales. Even worse, patents on five blockbuster drugs were about to expire, which would allow cheaper generics to flood the market. The company hadn't introduced a truly new product in three years, and its stock price was plummeting.

In interviews with the press, Edward Scolnick, Merck's research director, laid out his battle plan to restore the firm to preeminence. Key to his strategy was expanding the company's reach into the antidepressant market, where Merck had lagged while competitors like Pfizer and GlaxoSmithKline created some of the best-selling drugs in the world. "To remain dominant in the future," he told Forbes, "we need to dominate the central nervous system."

His plan hinged on the success of an experimental antidepressant codenamed MK-869. Still in clinical trials, it looked like every pharma executive's dream: a new kind of medication that exploited brain chemistry in innovative ways to promote feelings of well-being. The drug tested brilliantly early on, with minimal side effects, and Merck touted its game-changing potential at a meeting of 300 securities analysts.... ]]></description>
<pubDate>Tue, 08 May 2012 23:31:06 -0500</pubDate>
<guid>http://fitmarker.com/supplementation/placebos-are-getting-more-effective-drugmakers-are-desperate-to-know-why/</guid>
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<title>Functional Performance and Inflammatory Cytokines after Squat Exercises and Whole-Body Vibration in Elderly Individuals With Knee Osteoarthritis.</title>
<link>http://fitmarker.com/weight-training/functional-performance-and-inflammatory-cytokines-after-squat-exercises-and-whole-body-vibration-in-elderly-individuals-with-knee-osteoarthritis/</link>
<description><![CDATA[ OBJECTIVE:
To investigate the effects of squat exercises combined with whole-body vibration on the plasma concentration of inflammatory markers and the functional performance of elderly individuals with knee osteoarthritis.
DESIGN:
Clinical, prospective, randomized, single-blinded study.
SETTING:
Exercise Physiology Laboratory.
PARTICIPANTS:
Thirty-two elderly subjects with knee osteoarthritis were divided into three groups [i.e., squat exercises on a vibratory platform (platform group N= 11), squat exercises without vibration (squat group N= 10) and the control group (N=11)].
INTERVENTIONS:
The structured program of squat exercises in the platform and squat groups was conducted three times per week, on alternate days, for 12 weeks.
MAIN OUTCOME MEASURES:
Plasma sTNFR1 and sTNFR2 were measured using immunoassays (the ELISA method). The Western Ontario and McMaster University Osteoarthritis Index (WOMAC) questionnaire was used to evaluate self-reported physical function, pain and stiffness. The 6-minute walk test, the Berg balance scale, and gait speed were used to evaluate physical function.
RESULTS:
In the group that performed squat exercises on a vibratory platform, there were significant reductions in the plasma concentrations of the inflammatory markers sTNFR1 and sTNFR2 (p&amp;lt;0.001 and p&amp;lt;0.05, respectively) and self-reported pain (p&amp;lt;0.05) compared with the control group; however, there was an increase in balance (p&amp;lt;0.05) and speed and distance walked (p&amp;lt;0.05 and p&amp;lt;0.001, respectively). In addition, the group that performed squat exercises on a vibratory platform walked faster than the group that only performed squat exercises (p&amp;lt;0.01).
CONCLUSION:
The results suggest that whole-body vibration training improves self-perception of pain, balance, gait quality and inflammatory markers in elderly subjects with knee osteoarthritis.
Copyright © 2012 the American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved. ]]></description>
<pubDate>Tue, 08 May 2012 14:35:11 -0500</pubDate>
<guid>http://fitmarker.com/weight-training/functional-performance-and-inflammatory-cytokines-after-squat-exercises-and-whole-body-vibration-in-elderly-individuals-with-knee-osteoarthritis/</guid>
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<title>Associations of Maximal Strength and Muscular Endurance Test Scores with Cardiorespiratiory Fitness and Body Composition</title>
<link>http://fitmarker.com/weight-training/associations-of-maximal-strength-and-muscular-endurance-test-scores-with-cardiorespiratiory-fitness-and-body-composition/</link>
<description><![CDATA[ Abstract
The purpose of the present study was to assess the relationships between maximal strength and muscular endurance test scores additionally to previously widely studied measures of body composition and maximal aerobic capacity. 846 young men (25.5±5.0 yrs) participated in the study. Maximal strength was measured using isometric bench press, leg extension and grip strength. Muscular endurance tests consisted of push-ups, sit-ups and repeated squats. An indirect graded cycle ergometer test was used to estimate maximal aerobic capacity (VO2max). Body composition was determined with bioelectrical impedance. Moreover, waist circumference (WC) and height were measured and body mass index (BMI) calculated. Maximal bench press was positively correlated with push-ups (R=0.37, p&amp;lt;0.001), grip strength (R=0.12, p&amp;lt;0.001) and sit-ups (R=0.12, p&amp;lt;0.001) while maximal leg extension force revealed only a weak positive correlation with repeated squats (R=0.05, p&amp;lt;0.001,). However, moderate correlation between repeated squats and VO2max was found (R=0.30, p&amp;lt;0.001) In addition, BM and body fat correlated negatively with muscular endurance (R=0.10-0.22, p&amp;lt;0.001), while FFM and maximal isometric strength correlated positively (R=0.13-0.20, p&amp;lt;0.001). In conclusion, muscular endurance test scores were related to maximal aerobic capacity and body fat content, while fat free mass was associated with maximal strength test scores and thus is a major determinant for maximal strength. A contributive role of maximal strength to muscular endurance tests could be indentified for the upper, but not the lower extremities. These findings suggest that push-up test is not only indicative of body fat content and maximal aerobic capacity but also maximal strength of upper body, whereas repeated squat test is mainly indicative of body fat content and maximal aerobic capacity, but not maximal strength of lower extremities. ]]></description>
<pubDate>Tue, 08 May 2012 13:56:55 -0500</pubDate>
<guid>http://fitmarker.com/weight-training/associations-of-maximal-strength-and-muscular-endurance-test-scores-with-cardiorespiratiory-fitness-and-body-composition/</guid>
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<title>Glycemia and insulinemia in healthy subjects after lactose-equivalent meals of milk and other food proteins: the role of plasma         amino acids and incretins</title>
<link>http://fitmarker.com/foodnutrition/glycemia-and-insulinemia-in-healthy-subjects-after-lactose-equivalent-meals-of-milk-and-other-food-proteins-the-role-of-plasma-amino-acids-and-incretins/</link>
<description><![CDATA[ ABSTRACT
Background: Milk products deviate from other carbohydrate-containing foods in that they produce high insulin responses, despite their low GI. The insulinotropic mechanism of milk has not been elucidated.

Objective: The objective was to evaluate the effect of common dietary sources of animal or vegetable proteins on concentrations of postprandial blood glucose, insulin, amino acids, and incretin hormones [glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1] in healthy subjects.

Design: Twelve healthy volunteers were served test meals consisting of reconstituted milk, cheese, whey, cod, and wheat gluten with equivalent amounts of lactose. An equicarbohydrate load of white-wheat bread was used as a reference meal.

Results: A correlation was found between postprandial insulin responses and early increments in plasma amino acids; the strongest correlations were seen for leucine, valine, lysine, and isoleucine. A correlation was also obtained between responses of insulin and GIP concentrations. Reconstituted milk powder and whey had substantially lower postprandial glucose areas under the curve (AUCs) than did the bread reference (–62% and –57%, respectively). Whey meal was accompanied by higher AUCs for insulin (90%) and GIP (54%).

Conclusions: It can be concluded that food proteins differ in their capacity to stimulate insulin release, possibly by differently affecting the early release of incretin hormones and insulinotropic amino acids. Milk proteins have insulinotropic properties; the whey fraction contains the predominating insulin secretagogue. ]]></description>
<pubDate>Sat, 05 May 2012 16:40:30 -0500</pubDate>
<guid>http://fitmarker.com/foodnutrition/glycemia-and-insulinemia-in-healthy-subjects-after-lactose-equivalent-meals-of-milk-and-other-food-proteins-the-role-of-plasma-amino-acids-and-incretins/</guid>
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<title>Differences in insulin resistance do not predict weight loss in response to hypocaloric diets in healthy obese women.</title>
<link>http://fitmarker.com/weight-loss/differences-in-insulin-resistance-do-not-predict-weight-loss-in-response-to-hypocaloric-diets-in-healthy-obese-women/</link>
<description><![CDATA[ Abstract
The current study was initiated to determine whether insulin resistance and/or hyperinsulinemia affected the ability of obese individuals to lose weight in response to hypocaloric diets. Thirty-one obese, nondiabetic women, with values for body mass index ranging from 28.0-35.0 kg/m2, volunteered for this program. Resistance to insulin-mediated glucose disposal was assessed by determining their steady state plasma insulin and glucose concentration during the last 30 min of a 180-min infusion of somatostatin, insulin, and glucose. The total integrated insulin response to breakfast and lunch was also determined. After the baseline measurements, volunteers were placed on a hypocaloric diet calculated to lead to a minimum weekly loss of 1% of ideal body weight. Individuals who met the criteria after 30 days of dieting were defined as weight loss successes (n = 20) and continued on the diet for another 30 days. Individuals not meeting the criteria were designated as weight loss failures (n = 12) and were discharged from the study. There was a mean (+/-SEM) weight loss at 60 days of 9.2 +/- 0.4 kg in the 20 individuals defined as weight loss successes, but there was no correlation between weight loss and either steady state plasma glucose or the total integrated insulin response (r &amp;lt; 0.1; P &amp;gt; 0.83). Furthermore, using the same criteria to define insulin sensitivity and insulin resistance as those for therapeutic successes, the therapeutic failures comprised six insulin-sensitive and five insulin-resistant subjects. In summary, insulin-mediated glucose disposal varied widely in nondiabetic, obese women, and there was no relationship between baseline insulin resistance or total integrated insulin response and weight loss. It is concluded that the ability to lose weight on a calorie-restricted diet over a short time period does not vary in obese, healthy women as a function of insulin resistance or hyperinsulinemia. ]]></description>
<pubDate>Sat, 05 May 2012 16:38:28 -0500</pubDate>
<guid>http://fitmarker.com/weight-loss/differences-in-insulin-resistance-do-not-predict-weight-loss-in-response-to-hypocaloric-diets-in-healthy-obese-women/</guid>
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