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Nathan Goodyear

Muscle Hypertrophy 2011 - 0 views

www.unm.edu/...hypertrophy2011UNM.html

resistance training weight lifting muscle exercise weight training

shared by Nathan Goodyear on 20 Mar 15 - No Cached
  • mechanical tension, muscle damage and metabolic stress are the three primary factors that promote hypertrophy from exercise
  • The mechanical tension is directly related to intensity of the exercise, which is the key to stimulating muscle growth
  • Muscle damage, that leads to muscle soreness, from exercise training initiates an inflammatory response, which activates satellite cells growth processes
  • ...6 more annotations...
  • metabolic stress that is a result of the byproducts of anaerobic metabolism (i.e., hydrogen ions, lactate, inorganic phosphates) is now also believed to promote hormonal factors leading to muscle hypertrophy
  • The upper extremities tend to show more growth earlier then the lower body
  • Maximal growth occurs with loads between 80-95% of 1 repetition maximum
  • weightlifters and powerlifters show more favorable hypertrophy of type II (fast twitch) muscle fibers
  • body builders appear to have comparable hypertrophy in both the type I (slow twitch) and type II muscle fibers
  • Multi-joint exercises have been shown to produce larger increases of anabolic hormones than single-joint exercises
  • Nathan Goodyear on 20 Mar 15
     
    Review of the physiology of muscle building.  The authors review the evidence behind the types of muscle building exercises and the physiology responsible for muscle hypertrophy.  The authors point to Schoenfeld's description of mechanical tension, muscle damage, and metabolic stress to build muscle.
Nathan Goodyear

JISSN | Full text | International Society of Sports Nutrition position stand: creatine ... - 0 views

www.jissn.com/6

creatine sports nutrition exercise

shared by Nathan Goodyear on 27 Jan 14 - No Cached
  • the energy supplied to rephosphorylate adenosine diphosphate (ADP) to adenosine triphosphate (ATP) during and following intense exercise is largely dependent on the amount of phosphocreatine (PCr) stored in the muscle
  • Creatine is chemically known as a non-protein nitrogen
  • It is synthesized in the liver and pancreas from the amino acids arginine, glycine, and methionine
  • ...26 more annotations...
  • Approximately 95% of the body's creatine is stored in skeletal muscle
  • About two thirds of the creatine found in skeletal muscle is stored as phosphocreatine (PCr) while the remaining amount of creatine is stored as free creatine
  • The body breaks down about 1 – 2% of the creatine pool per day (about 1–2 grams/day) into creatinine in the skeletal muscle
  • The magnitude of the increase in skeletal muscle creatine content is important because studies have reported performance changes to be correlated to this increase
  • "loading" protocol. This protocol is characterized by ingesting approximately 0.3 grams/kg/day of CM for 5 – 7 days (e.g., ≃5 grams taken four times per day) and 3–5 grams/day thereafter [18,22]. Research has shown a 10–40% increase in muscle creatine and PCr stores using this protocol
  • Additional research has reported that the loading protocol may only need to be 2–3 days in length to be beneficial, particularly if the ingestion coincides with protein and/or carbohydrate
  • A few studies have reported protocols with no loading period to be sufficient for increasing muscle creatine (3 g/d for 28 days)
  • Cycling protocols involve the consumption of "loading" doses for 3–5 days every 3 to 4 weeks
  • Most of these forms of creatine have been reported to be no better than traditional CM in terms of increasing strength or performance
  • Recent studies do suggest, however, that adding β-alanine to CM may produce greater effects than CM alone
  • These investigations indicate that the combination may have greater effects on strength, lean mass, and body fat percentage; in addition to delaying neuromuscular fatigue
  • creatine phosphate has been reported to be as effective as CM at improving LBM and strength
  • Green et al. [24] reported that adding 93 g of carbohydrate to 5 g of CM increased total muscle creatine by 60%
  • Steenge et al. [23] reported that adding 47 g of carbohydrate and 50 g of protein to CM was as effective at promoting muscle retention of creatine as adding 96 g of carbohydrate.
  • It appears that combining CM with carbohydrate or carbohydrate and protein produces optimal results
  • Studies suggest that increasing skeletal muscle creatine uptake may enhance the benefits of training
  • Nearly 70% of these studies have reported a significant improvement in exercise capacity,
  • Long-term CM supplementation appears to enhance the overall quality of training, leading to 5 to 15% greater gains in strength and performance
  • Nearly all studies indicate that "proper" CM supplementation increases body mass by about 1 to 2 kg in the first week of loading
  • short-term adaptations reported from CM supplementation include increased cycling power, total work performed on the bench press and jump squat, as well as improved sport performance in sprinting, swimming, and soccer
  • Long-term adaptations when combining CM supplementation with training include increased muscle creatine and PCr content, lean body mass, strength, sprint performance, power, rate of force development, and muscle diameter
  • subjects taking CM typically gain about twice as much body mass and/or fat free mass (i.e., an extra 2 to 4 pounds of muscle mass during 4 to 12 weeks of training) than subjects taking a placebo
  • The gains in muscle mass appear to be a result of an improved ability to perform high-intensity exercise via increased PCr availability and enhanced ATP synthesis, thereby enabling an athlete to train harder
  • there is no evidence to support the notion that normal creatine intakes (< 25 g/d) in healthy adults cause renal dysfunction
  • no long-term side effects have been observed in athletes (up to 5 years),
  • One cohort of patients taking 1.5 – 3 grams/day of CM has been monitored since 1981 with no significant side effects
  • Nathan Goodyear on 27 Jan 14
     
    Nice review of the data, up to the publication date, on creatine.
Nathan Goodyear

Relationship between Low Free Testosterone Levels and Loss of Muscle Mass : Scientific ... - 0 views

www.nature.com/...srep01818.html

muscle men male hormone Testosterone free Testosterone low T low Testosterone

shared by Nathan Goodyear on 05 Mar 15 - No Cached
  • Our data confirm that a low FT level is a significant predictor of a risk for loss of appendicular muscle
  • Total lean mass is associated with bioavailable T in postmenopausal women
  • Further studies are needed to determine the role of androgens in preserving muscle mass in women
  • ...11 more annotations...
  • Approximately 1% to 2% of T in the blood exists as FT
  • appendicular muscle loss was significantly associated with low levels of FT
  • These results suggest that a threshold level of FT exists for muscle loss, rather than a dose-response relationship
  • In the previous cross-sectional and longitudinal studies of French and American men, no dose-response relationships were reported between T and muscle mass
  • A minimal serum level of FT may be needed to preserve muscle mass in men, regardless of race/ethnicity.
  • Our result is in line with previous studies that reported a relationship between low FT and low muscle mass in men
  • T stimulates protein synthesis and inhibits protein degradation in muscle cells
  • T also increases satellite cell replication and activation in older men
  • In this study, no significant association between TT levels and muscle loss were observed
  • Although a progressive decrease in TT levels with ageing is observed in middle-aged and elderly American men16, 17, the TT levels do not change during ageing in Japanese men
  • FT levels may be a good marker for the loss of muscle mas
  • Nathan Goodyear on 05 Mar 15
     
    study of Japanese men finds that low free Testosterone was a predictor of decrease in muscle mass.
Nathan Goodyear

Effect of resistance exercise on muscle steroidogenesis | Journal of Applied Physiology - 0 views

jap.physiology.org/...1754

resistance resistance training training exercise Testosterone male female hormone hormones muscle

shared by Nathan Goodyear on 03 Sep 14 - No Cached
  • skeletal muscle cell cultures incubated with DHEA produced testosterone in a DHEA dose-dependent manner
  • Muscle joins a growing list of tissues found to be capable of steroidogenesis
  • testosterone appears to have a role in the maintenance of muscle mass in women, although the importance of this role has not yet been fully established.
  • ...7 more annotations...
  • Circulating testosterone concentrations are generally elevated following a bout of resistance exercise in men (24, 31, 46, 52), whereas findings for the effect of resistance exercise on circulating testosterone in women are equivocal, with increases (10, 42) and no changes observed (22, 31)
  • swimming (51) and treadmill running (2) can significantly increase muscle testosterone concentrations in male and female rats
  • This upregulation of muscle testosterone in rats appears, at least in part, to be due to an increase in 3β-HSD and 17β-HSD type 1 expression
  • The primary finding in this study was that muscle steroidogenesis (i.e., testosterone production) in highly resistance-trained humans was not affected by an acute bout of heavy resistance exercise
  • A secondary finding was that the apparent molecular mass of 17β-HSD type 3 was increased following a single bout of heavy resistance exercise.
  • No differences were found for muscle testosterone or steroidogenic enzyme (17β-HSD type 3 and 3β-HSD types 1 and 2) concentrations between sexes or in response to resistance exercise
  • In conclusion, heavy resistance exercise did not induce changes in muscle steroidogenesis as measured by muscle concentrations of testosterone, 3β-HSD types 1 and 2, and 17β-HSD type 3 in highly resistance-trained young men and women.
  • Nathan Goodyear on 03 Sep 14
     
    Resistance exercise did not increase muscle concentrations of Testosterone in men or women.  The individuals in this study were actively training.  These were not sedentary individuals.
Nathan Goodyear

Cell Metabolism - The Ubiquitin Ligase Mul1 Induces Mitophagy in Skeletal Muscle in Res... - 0 views

www.cell.com/...S1550413112004056

muscle wasting mitochondria energy metabolism

shared by Nathan Goodyear on 02 Jan 13 - No Cached
  • Nathan Goodyear on 02 Jan 13
     
    loss of mitochondria leads to muscle wasting.  Kind of makes sense.  The muscles lose the ability to make energy and thus the muscle cells die and waste.  Thus, preserve mitochondrial function and you will slow muscle wasting.
Nathan Goodyear

An integrative analysis reveals coordinated reprogramming of the epigenome and the tran... - 0 views

www.ncbi.nlm.nih.gov/...PMC4622000

exercise epigenetics muscle

shared by Nathan Goodyear on 03 Oct 17 - No Cached
  • contribution to the training response of the epigenome as a mediator between genes and environment
  • Differential DNA methylation was predominantly observed in enhancers, gene bodies and intergenic regions and less in CpG islands or promoters
  • highly consistent and associated modifications in methylation and expression, concordant with observed health-enhancing phenotypic adaptations, are induced by a physiological stimulus
  • ...34 more annotations...
  • The health benefits following exercise training are elicited by gene expression changes in skeletal muscle, which are fundamental to the remodeling process
  • there is increasing evidence that more short-term environmental factors can influence DNA methylation
  • dietary factors have the potency to alter the degree of DNA methylation in different tissues, 9,10 including skeletal muscle
  • In one study, a single bout of endurance-type exercise was shown to affect methylation at a few promoter CpG sites
  • In the context of diabetes, exercise training has been shown to affect genome-wide methylation pattern in skeletal muscle,13 as well as in adipose tissue.
  • physiological stressors can indeed affect DNA methylation
  • training intervention reshapes the epigenome and induces significant changes in DNA methylation
  • the findings from this tightly controlled human study strongly suggest that the regulation and maintenance of exercise training adaptation is to a large degree associated to epigenetic changes, especially in regulatory enhancer regions
  • Endurance training [after training (T2) vs. before training (T1)] induced significant (false discovery rate, FDR< 0.05) methylation changes at 4919 sites across the genome in the trained leg
  • identified 4076 differentially expressed genes
  • a complementary approach revealed that over 600 CpG sites correlated to the increase in citrate synthase activity, an objective measure of training response (Figure S4 and Dataset S14). This might imply that some of these sites could influence the degree of training response.
  • As expected by a physiological environmental trigger on adult tissue, the observed effect size on DNA methylation was small in comparison to disease states such as cancer
  • a preferential localization outside of CpG Islands/Shelves/Shores
  • endurance training especially influences enhancers
  • negative correlation was more prominent for probes in promoter/5′UTR/1st exon regions, while gene bodies had a stronger peak of positive correlation
  • The significant changes in DNA methylation, that primarily occurred in enhancer regions, were to a large extent associated with relevant changes in gene expression
  • The main findings of this study were that 3 months of endurance training in healthy human volunteers induced significant methylation changes at almost 5000 sites across the genome and significant differential expression of approximately 4000 genes
  • DMPs that increased in methylation were mainly associated to structural remodeling of the muscle and glucose metabolism, while the DMPs with decreased methylation were associated to inflammatory/immunological processes and transcriptional regulation
  • This suggests that the changes in methylation seen with training were not a random effect across the genome but rather a controlled process that likely contributes to skeletal muscle adaptation to endurance training
  • Correlation of the changes in DNA methylation to the changes in gene expression showed that the majority of significant methylation/expression pairs were found in the groups representing either increases in expression with a concomitant decrease in methylation or vice versa
  • The fraction of genes showing both significant decrease in methylation and upregulation was 7.5% of the DEGs or 2.3% of all genes detected in muscle tissue with at least one measured DNA methylation position. Correspondingly, 7.0% of the DEGs or 2.1% of all genes showed both significant increase in methylation and downregulation
  • we show that DNA methylation changes are associated to gene expression changes in roughly 20% of unique genes that significantly changed with training
  • Examples of structural genes include COL4A1, COL4A2 and LAMA4. These genes have also been identified as important for differences in responsiveness to endurance training
  • methylation status could be part of the mechanism behind variable training response
  • Among the metabolic genes, MDH1 catalyzes the reversible oxidation of malate to oxaloacetate, utilizing the NAD/NADH cofactor system in the citric acid cycle and NDUFA8 plays an important role in transferring electrons from NADH to the respiratory chain
  • PPP1R12A,
  • In the present study, methylation predominantly changed in enhancer regions with enrichment for binding motifs for different transcription factors suggesting that enhancer methylation may be highly relevant also in exercise biology
  • Of special interest in the biology of endurance training may be that MRFs, through binding to the PGC-1α core promoter, can regulate this well-studied co-factor for mitochondrial biogenesis
  • That endurance training led to an increased methylation in enhancer regions containing motifs for the MRFs and MEFs is somewhat counterintuitive since it should lead to the repression of the action of the above discussed transcription factors
  • decrease with training in this study, including CDCH15, MYH3, TNNT2, RYR1 and SH3GLB1
  • expression of MEF2A itself decreased with training
  • this study demonstrates that the transcriptional alterations in skeletal muscle in response to a long-term endurance exercise intervention are coupled to DNA methylation changes
  • We suggest that the training-induced coordinated epigenetic reprogramming mainly targets enhancer regions, thus contributing to differences in individual response to lifestyle interventions
  • a physiological health-enhancing stimulus can induce highly consistent modifications in DNA methylation that are associated to gene expression changes concordant with observed phenotypic adaptations
  • Nathan Goodyear on 03 Oct 17
     
    Exercise alters gene expression via methylation--the power of epigenetics.  Interestingly, the majority of the methylation was outside the CPG island regions.  This 3 month study found methylation of 5,000 sites across the genome resulting in altered expression of apps 4,000 genes.  The altered muscle changes of the endurance training was linked to DNA methylation changes.
wheelchairindia9

Weight Cuff - 0 views

www.wheelchairindia.com/...Tynor-Weight-Cuff

The Best Exercise for Strengthening Shoulders improve muscle strength Iron pellets filled cuff multiple sclerosis patients rehab therapy programs allowing sufficient flexibility

shared by wheelchairindia9 on 06 Apr 16 - No Cached
  • wheelchairindia9 on 06 Apr 16
     
    Tynor Weight Cuff Tynor Weight cuffs are used to exercise ailing joints to build strength and aid recovery. Tynor Weight Cuff is flexible and cushion, so it does not injure. Recommended for use to improve muscle tone, muscle mass, strength and stamina. Tynor Weight Cuff Features Offers 1 kg resistance when wrapped around Weight is wrapped in comfortable and soft fabric Used to build muscles, flexibility or to lose weight Can be secured easily around to prevent injuries or accidents Cuff is safe to be used during everyday activities as well Tynor Weight Cuff Measurements Sizes Available: 1/2 Kg / 1Kg / 2 Kg
krsnaphysio1

Physiotherapist in Gurgaon - 0 views

krsnaphysioplus.com/...physiotherapist-in-gurgaon

physiotherapist physiotherapy

shared by krsnaphysio1 on 26 Nov 19 - No Cached
  • krsnaphysio1 on 26 Nov 19
     
    Since its establishment in the year 2011, Krshna Physio Plus is aimed to provide patients with comprehensive, high quality and professional physiotherapy treatments and rehabilitation to people in need. The efficient team of three, Dr. Ravi Sahauta - A very well-known complex trauma surgeon and Orthopaedician, Dr. Dharm Pal Sharma - an ex-Air force Physio trainer and Dr. Parmila Sharma - an experienced and talented physio expert, Krshna Physio Plus is counted among the well-known Physiotherapy clinic in Gurgaon and Delhi/NCR regions.  This clinic is one of the oldest organizations which was started with a vision to help people suffering from diverse dysfunctionalities with proper guidance and treatment which encompasses mainly physical, psychological, emotional, and social well being. With 8 centers in Delhi/NCR and Bihar, we are aimed at setting over 300 centers across Asia by 2020 and become the Physiotherapy clinic in Gurgaon.  Moreover, KRSNA Physio Plus is well equipped with various advanced facilities and equipment used to treat people to assure patient satisfaction and fast recovery. We have with us Top Physiotherapist in Gurgaon and Delhi/NCR regions with us who are specialized in offering treatment in physiotherapy dealing with Orthopedic, Neurological, Pediatric, Cardio-pulmonary, and Sports Injury, etc. All the experts here put their best for providing the best results.  Our experienced team of doctors and physiotherapists in Gurgaon who would be better able to diagnose what might be making it impossible for you to crane your neck, or pick articles off the floor, or simply kneel before your deity. Sports-Related Injuries Could Happen to Anyone It could be just that badminton match on a winter evening, or an office football match. Before you realize what is happening you've pulled a back muscle or your hamstring. Playing tug-of-war in colleges and office parties is fraught with the risk of a rotator cuff injury. Cricketers diving to save
Nathan Goodyear

Testosterone and the Cardiovascular System: A Comprehensive Review of the Clinical Lite... - 0 views

jaha.ahajournals.org/...e000272.full

Testosterone men male cardiovascular disease low T

shared by Nathan Goodyear on 20 Nov 13 - No Cached
  • Low endogenous bioavailable testosterone levels have been shown to be associated with higher rates of all‐cause and cardiovascular‐related mortality.39,41,46–47 Patients suffering from CAD,13–18 CHF,137 T2DM,25–26 and obesity27–28
  • have all been shown to have lower levels of endogenous testosterone compared with those in healthy controls. In addition, the severity of CAD15,17,29–30 and CHF137 correlates with the degree of testosterone deficiency
  • In patients with CHF, testosterone replacement therapy has been shown to significantly improve exercise tolerance while having no effect on LVEF
  • ...66 more annotations...
  • testosterone therapy causes a shift in the skeletal muscle of CHF patients toward a higher concentration of type I muscle fibers
  • Testosterone replacement therapy has also been shown to improve the homeostatic model of insulin resistance and hemoglobin A1c in diabetics26,68–69 and to lower the BMI in obese patients.
  • Lower levels of endogenous testosterone have been associated with longer duration of the QTc interval
  • testosterone replacement has been shown to shorten the QTc interval
  • negative correlation has been demonstrated between endogenous testosterone levels and IMT of the carotid arteries, abdominal aorta, and thoracic aorta
  • These findings suggest that men with lower levels of endogenous testosterone may be at a higher risk of developing atherosclerosis.
  • Current guidelines from the Endocrine Society make no recommendations on whether patients with heart disease should be screened for hypogonadism and do not recommend supplementing patients with heart disease to improve survival.
  • The Massachusetts Male Aging Study also projects ≈481 000 new cases of hypogonadism annually in US men within the same age group
  • since 1993 prescriptions for testosterone, regardless of the formulation, have increased nearly 500%
  • Testosterone levels are lower in patients with chronic illnesses such as end‐stage renal disease, human immunodeficiency virus, chronic obstructive pulmonary disease, type 2 diabetes mellitus (T2DM), obesity, and several genetic conditions such as Klinefelter syndrome
  • A growing body of evidence suggests that men with lower levels of endogenous testosterone are more prone to develop CAD during their lifetimes
  • There are 2 major potential confounding factors that the older studies generally failed to account for. These factors are the subfraction of testosterone used to perform the analysis and the method used to account for subclinical CAD.
  • The biologically inactive form of testosterone is tightly bound to SHBG and is therefore unable to bind to androgen receptors
  • The biologically inactive fraction of testosterone comprises nearly 68% of the total testosterone in human serum
  • The biologically active subfraction of testosterone, also referred to as bioavailable testosterone, is either loosely bound to albumin or circulates freely in the blood, the latter referred to as free testosterone
  • It is estimated that ≈30% of total serum testosterone is bound to albumin, whereas the remaining 1% to 3% circulates as free testosterone
  • it can be argued that using the biologically active form of testosterone to evaluate the association with CAD will produce the most reliable results
  • English et al14 found statistically significant lower levels of bioavailable testosterone, free testosterone, and free androgen index in patients with catheterization‐proven CAD compared with controls with normal coronary arteries
  • patients with catheterization‐proven CAD had statistically significant lower levels of bioavailable testosterone
  • In conclusion, existing evidence suggests that men with CAD have lower levels of endogenous testosterone,13–18 and more specifically lower levels of bioavailable testosterone
  • low testosterone levels are associated with risk factors for CAD such as T2DM25–26 and obesity
  • In a meta‐analysis of these 7 population‐based studies, Araujo et al41 showed a trend toward increased cardiovascular mortality associated with lower levels of total testosterone, but statistical significance was not achieved (RR, 1.25
  • the authors showed that a decrease of 2.1 standard deviations in levels of total testosterone was associated with a 25% increase in the risk of cardiovascular mortality
  • the relative risk of all‐cause mortality in men with lower levels of total testosterone was calculated to be 1.35
  • higher risk of cardiovascular mortality is associated with lower levels of bioavailable testosterone
  • Existing evidence seems to suggest that lower levels of endogenous testosterone are associated with higher rates of all‐cause mortality and cardiovascular mortality
  • studies have shown that lower levels of endogenous bioavailable testosterone are associated with higher rates of all‐cause and cardiovascular mortality
  • It may be possible that using bioavailable testosterone to perform mortality analysis will yield more accurate results because it prevents the biologically inactive subfraction of testosterone from playing a potential confounding role in the analysis
  • The earliest published material on this matter dates to the late 1930s
  • the concept that testosterone replacement therapy improves angina has yet to be proven wrong
  • In more recent studies, 3 randomized, placebo‐controlled trials demonstrated that administration of testosterone improves myocardial ischemia in men with CAD
  • The improvement in myocardial ischemia was shown to occur in response to both acute and chronic testosterone therapy and seemed to be independent of whether an intravenous or transdermal formulation of testosterone was used.
  • testosterone had no effect on endothelial nitric oxide activity
  • There is growing evidence from in vivo animal models and in vitro models that testosterone induces coronary vasodilation by modulating the activity of ion channels, such as potassium and calcium channels, on the surface of vascular smooth muscle cells
  • Experimental studies suggest that the most likely mechanism of action for testosterone on vascular smooth muscle cells is via modulation of action of non‐ATP‐sensitive potassium ion channels, calcium‐activated potassium ion channels, voltage‐sensitive potassium ion channels, and finally L‐type calcium ion channels
  • Corona et al confirmed those results by demonstrating that not only total testosterone levels are lower among diabetics, but also the levels of free testosterone and SHBG are lower in diabetic patients
  • Laaksonen et al65 followed 702 Finnish men for 11 years and demonstrated that men in the lowest quartile of total testosterone, free testosterone, and SHBG were more likely to develop T2DM and metabolic syndrome.
  • Vikan et al followed 1454 Swedish men for 11 years and discovered that men in the highest quartile of total testosterone were significantly less likely to develop T2DM
  • authors demonstrated a statistically significant increase in the incidence of T2DM in subjects receiving gonadotropin‐releasing hormone antagonist therapy. In addition, a significant increase in the rate of myocardial infarction, stroke, sudden cardiac death, and development of cardiovascular disease was noted in patients receiving antiandrogen therapy.67
  • Several authors have demonstrated that the administration of testosterone in diabetic men improves the homeostatic model of insulin resistance, hemoglobin A1c, and fasting plasma glucose
  • Existing evidence strongly suggests that the levels of total and free testosterone are lower among diabetic patients compared with those in nondiabetics
  • insulin seems to be acting as a stimulant for the hypothalamus to secret gonadotropin‐releasing hormone, which consequently results in increased testosterone production. It can be argued that decreased stimulation of the hypothalamus in diabetics secondary to insulin deficiency could result in hypogonadotropic hypogonadism
  • BMI has been shown to be inversely associated with testosterone levels
  • This interaction may be a result of the promotion of lipolysis in abdominal adipose tissue by testosterone, which may in turn cause reduced abdominal adiposity. On the other hand, given that adipose tissue has a higher concentration of the enzyme aromatase, it could be that increased adipose tissue results in more testosterone being converted to estrogen, thereby causing hypogonadism. Third, increased abdominal obesity may cause reduced testosterone secretion by negatively affecting the hypothalamus‐pituitary‐testicular axis. Finally, testosterone may be the key factor in activating the enzyme 11‐hydroxysteroid dehydrogenase in adipose tissue, which transforms glucocorticoids into their inactive form.
  • increasing age may alter the association between testosterone and CRP. Another possible explanation for the association between testosterone level and CRP is central obesity and waist circumference
  • Bai et al have provided convincing evidence that testosterone might be able to shorten the QTc interval by augmenting the activity of slowly activating delayed rectifier potassium channels while simultaneously slowing the activity of L‐type calcium channels
  • consistent evidence that supplemental testosterone shortens the QTc interval.
  • Intima‐media thickness (IMT) of the carotid artery is considered a marker for preclinical atherosclerosis
  • Studies have shown that levels of endogenous testosterone are inversely associated with IMT of the carotid artery,126–128,32,129–130 as well as both the thoracic134 and the abdominal aorta
  • 1 study has demonstrated that lower levels of free testosterone are associated with accelerated progression of carotid artery IMT
  • another study has reported that decreased levels of total and bioavailable testosterone are associated with progression of atherosclerosis in the abdominal aorta
  • These findings suggest that normal physiologic testosterone levels may help to protect men from the development of atherosclerosis
  • Czesla et al successfully demonstrated that the muscle specimens that were exposed to metenolone had a significant shift in their composition toward type I muscle fibers
  • Type I muscle fibers, also known as slow‐twitch or oxidative fibers, are associated with enhanced strength and physical capability
  • It has been shown that those with advanced CHF have a higher percentage of type II muscle fibers, based on muscle biopsy
  • Studies have shown that men with CHF suffer from reduced levels of total and free testosterone.137 It has also been shown that reduced testosterone levels in men with CHF portends a poor prognosis and is associated with increased CHF mortality.138 Reduced testosterone has also been shown to correlate negatively with exercise capacity in CHF patients.
  • Testosterone replacement therapy has been shown to significantly improve exercise capacity, without affecting LVEF
  • the results of the 3 meta‐analyses seem to indicate that testosterone replacement therapy does not cause an increase in the rate of adverse cardiovascular events
  • Data from 3 meta‐analyses seem to contradict the commonly held belief that testosterone administration may increase the risk of developing prostate cancer
  • One meta‐analysis reported an increase in all prostate‐related adverse events with testosterone administration.146 However, when each prostate‐related event, including prostate cancer and a rise in PSA, was analyzed separately, no differences were observed between the testosterone group and the placebo group
  • the existing data from the 3 meta‐analyses seem to indicate that testosterone replacement therapy does not increase the risk of adverse cardiovascular events
  • the authors correctly point out the weaknesses of their study which include retrospective study design and lack of randomization, small sample size at extremes of follow‐up, lack of outcome validation by chart review and poor generalizability of the results given that only male veterans with CAD were included in this study
    • Nathan Goodyear
      Nathan Goodyear on 04 Dec 13
       
      The authors here present Total Testosterone as a "confounding" value
    • Nathan Goodyear
      Nathan Goodyear on 09 Dec 13
       
      This would be HSD-II
  • the studies that failed to find an association between testosterone and CRP used an older population group
  • low testosterone may influence the severity of CAD by adversely affecting the mediators of the inflammatory response such as high‐sensitivity C‐reactive protein, interleukin‐6, and tumor necrosis factor–α
  • Nathan Goodyear on 20 Nov 13
     
    Good review of Testosterone and CHD.  Low T is associated with increased all cause mortality and cardiovascular mortality, CAD, CHF, type II diabetes, obesity, increased IMT,  increased severity of CAD and CHF.  Testosterone replacement in men with low T has been shown to improve exercise tolerance in CHF, improve insulin resistance, improve HgbA1c and lower BMI in the obese.
Nathan Goodyear

Impact of an Exercise Intervention on DNA Methylation in Skeletal Muscle From First-Deg... - 0 views

www.ncbi.nlm.nih.gov/...PMC3501844

exercise diabetes epigenetics muscle mitochondria VO2max

shared by Nathan Goodyear on 03 Oct 17 - No Cached
  • epigenetic modifications of single genes have been shown to affect the pathogenesis of T2D
  • An FH of T2D is an independent predictor of future risk for the disease
  • exercise for 6 months is associated with epigenetic changes, e.g., decreased DNA methylation of RUNX1 and MEF2A, two key transcription factors involved in exercise training (42–44), of THADA, previously associated with T2D (1), and of NDUFC2, which is part of the respiratory chain (45) was observed after exercise
  • ...4 more annotations...
  • exercise changed both DNA methylation and expression of a number of genes, including ADIPOR1, ADIPOR2, and BDKRB2, encoding receptors for adiponectin and bradykinin, respectively, which both regulate metabolism in muscle
  • we cannot draw a conclusion as to whether differential expression is a consequence rather than a cause of changes in methylation
  • ageing is associated with increased DNA methylation and decreased expression of genes involved in oxidative phosphorylation in human muscle
  • exercise can induce genome-wide epigenetic changes in human muscle and that the response may differ in people with different genetic predispositions to metabolic disease
  • Nathan Goodyear on 03 Oct 17
     
    Six months of exercise induce epigenetic changes through decrease in methylation.  This study was designed to look at those with a family risk of DM.  They found a difference in the methylation status of muscle between those with a family h/o diabetes and those without.  This would have implications in therapeutic difference prior to diagnosis.  Even a increased VO2max and skeletal muscle mitochondrial density was found to be the result of decreased methylation of the NDUFC2 gene after exercise.
Nathan Goodyear

Counteracting muscle wasting in HIV-infected individuals - 0 views

trace.tennessee.edu/...viewcontent.cgi

muscle mass low T low testosterone HGH men male

shared by Nathan Goodyear on 12 Nov 12 - No Cached
  • Nathan Goodyear on 12 Nov 12
     
    HIV/AIDS patients are plagues with muscle loss through varying mechanism. This article discusses the various contributors to the muscle mass found in these men. However, this can be applicable to other men with chronic muscle loss, low T, HGH deficiency...
Nathan Goodyear

Exercise-Associated Muscle Cramps - 0 views

www.ncbi.nlm.nih.gov/...PMC3445088

EAMC exercise associated muscle cramps athletes muscle cramps

shared by Nathan Goodyear on 27 Jan 15 - No Cached
  • athletes who develop EAMC often ingest similar amounts of fluid during exercise as do their noncramping counterparts
  • Oral fluid ingestion may be ineffective, and intravenous fluid may provide a faster delivery for athletes suffering from acute EAMC
  • It is interesting that stretching the affected muscle almost immediately relieves EAMC
  • ...9 more annotations...
  • Stretching, the primary treatment for acute EAMC
  • National Athletic Trainers’ Association recommends that athletes prone to muscle cramping add 0.3 to 0.7 g/L of salt to their drinks to stave off muscle cramps
  • Others have recommended adding higher amounts of sodium (about 3.0 to 6.0 g/L) to sports drinks based on the frequency of EAMC
  • intravenous infusion of fluids removes this delay, and it has been used to aid athletes who develop acute EAMC
  • maintaining hydration and adequate electrolyte levels is a good prevention strategy for individuals susceptible to EAMC
  • Fluid volumes of 1.8 L per hour have been well tolerated by tennis athletes who are susceptible to EAMC
  • Monitoring an athlete’s body weight is an easy method of ensuring adequate fluid replacement and individualizes each athlete’s fluid needs
  • the National Athletic Trainers’ Association and the American College of Sports Medicine recommend a volume of fluid that allows for less than a 2% body weight reduction
  • Endurance training may also serve as an effective means of preventing EAMC by expanding plasma volume and the extracellular fluid compartment15 and delaying neuromuscular fatigue
  • Nathan Goodyear on 27 Jan 15
     
    Exercise associated muscle cramps or EAMC is not worked out.  The theories include dehydration, mineral/electrolyte deficiencies, and neuromuscular activity.
wheelchairindia9

Hip Cycle - 0 views

www.wheelchairindia.com/...Hip-Cycle

Hip Cycle buy hip cycle exerciser hip cycle exerciser Vissco Hip Cycle Exerciser Vissco Hip Cycle hip cycles new hip cycle exerciser new hip cycle hip cycle home exerciser

shared by wheelchairindia9 on 24 Feb 16 - No Cached
  • wheelchairindia9 on 24 Feb 16
     
    Hip Cycle is a stationary regular cycle exerciser used in physical therapy and as a sports fitness aid. Cycling is a low-impact exercise to increase muscle strength and mobility of the hips and knees. Cycling assists in hip toning by muscle growth and burning of calories. Hip Cycle Features Pedaling uses thigh muscles: quadriceps to push down, and hamstrings to pull up during the circular motion Cycling workout results in isometric engagement of the abdomen as a supporting muscle group Range of motion exercises help improve joint function Reduce hip pain caused by bone diseases such as osteoarthritis and necrosis Hip Cycle can be used in preferably recumbent position or in sitting position
Nathan Goodyear

Estrogenic regulation of skeletal muscle proteome: a study of premenopausal women and p... - 0 views

onlinelibrary.wiley.com/...full

estradiol menopause muscle hormones mitochondria aging female

shared by Nathan Goodyear on 10 Oct 17 - No Cached
  • Female aging is characterized by menopausal change in sex steroid hormones concomitant to increase in aging-related decrements in skeletal muscle performance that can be attenuated by HRT use
  • The major canonical pathways found to be differentially regulated included mitochondrial dysfunction, oxidative phosphorylation, glycolysis, and TCA-cycle, strong indicators for affected energy metabolism
  • E2 to exert anti-apoptotic effects in muscle progenitor cells by improving mitochondrial function
  • ...2 more annotations...
  • E2 is a major regulator of human skeletal muscle signaling in women
  • After menopause, when ovarian E2 production is ceased, the prevalence of cardio-metabolic diseases increases. Our result that different trajectories of the energy pathways in the skeletal muscle may be regulated by E2 provides candidate molecules as key targets for future interventions to prevent or treat postmenopausal metabolic dysregulation
  • Nathan Goodyear on 10 Oct 17
     
    Study finds Estradiol regulates human skeletal muscle cell signaling (mitochondrial function, oxidative phosphorylation, glycolysis, and TCA cycle) in study of pre/post menopause women through proteome analysis. This study would have been complete if they had carried to search beyond that of protein to epigenetics.
Nathan Goodyear

Branched-chain amino acids and muscle ammoni... [Metab Brain Dis. 2013] - PubMed - NCBI - 0 views

www.ncbi.nlm.nih.gov/...23315357

NH3 muscle brain urea cycle metabolism BCAA branched chain amino acids liver cirrhosis disease

shared by Nathan Goodyear on 10 Feb 14 - No Cached
  • BCAA metabolism may improve muscle net ammonia removal by supplying carbon skeletons for formation of alfa-ketoglutarate that combines with two ammonia molecules to become glutamine
  • Nathan Goodyear on 10 Feb 14
     
    Muscle becomes the primary mode of NH3 metabolism in liver cirrhosis.  The authors here propose that it is via an increase in muscle mass rather than specifically lowering NH3.  In fact, there is an early increase in NH3 production.
Nathan Goodyear

The Effects of Pre-Exercise Ginger Supplementation on Muscle Damage and Delayed Onset M... - 0 views

www.ncbi.nlm.nih.gov/...25787877

ginger muscle sports medicine sports sports injury

shared by Nathan Goodyear on 28 Aug 15 - No Cached
  • Nathan Goodyear on 28 Aug 15
     
    Could Ginger be aid in recovery?  Results are mixed.  Study finds 4 g of ginger improves strength in muscle recovery, yet no change in muscle biomarkers.
Nathan Goodyear

Predictors of skeletal muscle mass in elderly men and women - 0 views

www.sciencedirect.com/...S0047637498001304

Testosterone free Testosterone muscle muscle mass men women male female hormone hormones

shared by Nathan Goodyear on 05 Mar 15 - No Cached
  • Nathan Goodyear on 05 Mar 15
     
    Study of men and women finds that low free Testosterone, physical activity, and IGF1 is associated with muscle mass in men; no such relationship between sex hormone and muscle mass in women was found.
Nathan Goodyear

Regulation of muscle mass by growth hormone and IGF-I - 0 views

www.ncbi.nlm.nih.gov/...PMC2439518

muscle hormones muscle mass GH growth hormone IGF-1

shared by Nathan Goodyear on 14 Apr 15 - No Cached
  • Nathan Goodyear on 14 Apr 15
     
    good review of GH and IGF-1 impact on muscle growth/muscle loss.
wheelchairindia9

Chest Binder - 0 views

www.wheelchairindia.com/...Tynor-Chest-Binder

The Best Exercise for Strengthening Shoulders improve muscle strength Iron pellets filled cuff multiple sclerosis patients rehab therapy programs allowing sufficient flexibility

shared by wheelchairindia9 on 06 Apr 16 - No Cached
  • wheelchairindia9 on 06 Apr 16
     
    Tynor Chest Binder Chest Binder is applied to the thoracic region to compress and bind the rib cage and provide splinting to the sternum while allowing sufficient flexibility for comfortable breathing. Anatomic chest pad. Controlled compression. Optimum chest splinting. Soft feel. Tynor Chest Binder Features 50 mm thick PUF pad hold and binds the fractured sternum without compromising on patient comfort. Strong elastic band gives good grip and helps in equidistribution of pressure. Reduces post operative pain and discomfiture. Facilitates phlegm expulsion after cardio thoracic surgery. Tynor Chest Binder Measurements Measure circumference around the chest.
Nathan Goodyear

Frontiers | Branched-Chain Amino Acid Ingestion Stimulates Muscle Myofibrillar Protein ... - 1 views

journal.frontiersin.org/...full

BCAA amino acids resistance training exercise recovery exercise muscle

shared by Nathan Goodyear on 18 Jul 17 - No Cached
  • BCAAs exhibit the capacity to stimulate myofibrillar-MPS, however a full complement of EAA could be necessary to stimulate a maximal response of myofibrillar-MPS following resistance exercise
  • This information potentially has important nutritional implications for selecting amino acid supplements to facilitate skeletal muscle hypertrophy in response to resistance exercise training and the maintenance of muscle mass during aging, unloading, or disease
  • results from the present study suggest that ingesting BCAAs alone, without the other EAA, provides limited substrate for protein synthesis in exercised muscles
  • ...3 more annotations...
  • the overall response of MPS is not maximized. Instead, the limited availability of EAA likely explains the qualitative difference in magnitude of the MPS response to ingestion of BCAAs alone and ingestion of similar amounts of BCAAs as part of intact whey protein
  • decreased EAA concentrations following leucine ingestion
  • these data support the notion that EAA availability is the rate-limiting factor for stimulating a maximal MPS response to resistance exercise with BCAA ingestion
  • Nathan Goodyear on 18 Jul 17
     
    Complete amino acid supplementation exceeds muscle building capacity (myofibrillar-MPS) over BCAA alone.
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