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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

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.
fitspresso

https://www.thefastleanpro.us/ - 0 views

www.thefastleanpro.us

the fast lean pro us usa fastlean fastleanpro caps drops uk buy jar get customer benefits 2023 work scam pros ebay pro2023 drop price

shared by fitspresso on 27 Sep 23 - No Cached
  • fitspresso on 27 Sep 23
     
    Fast Lean Pro™ (official) | weight lose Formula thefastleanpro.us · by Fast Lean Pro Fast Lean Pro Only $49/Bottle Limited Time Offer! Fast Lean Pro Special Deal + Special 51% Discount Save $300 + 180 Days Money Back Guarantee FastLeanPro The #1 Solution To natural metabolism booster helps you lose weight quickly without starving yourself. Fast Lean Pro is a natural powder supplement for weight loss that has recently been developed by Japanese scientists. Regular Price: $99/per bottle Only for: $49/per bottle What Is Fast Lean Pro? Fast Lean Pro is a powdered dietary powdery supplement designed to aid in weight loss. It contains a unique combination of ingredients that are believed to activate the body's "fasting switch" to optimize results. This product focuses not only on weight loss but also on promoting cellular rejuvenation, fasting, and a healthy metabolism. The concept behind Fast Lean Pro is that incorporating fasting into one's lifestyle can lead to positive outcomes irrespective of individual food choices and eating habits. To comprehend the mechanism of the Fast Lean Pro process, it is necessary to delve into its specific details. One of the few weight loss pills on the market that contains Fibersol is Fast Lean Pro. This safe, specialized fiber adds bulk to its weight when combined with water, curbing your appetite before it throws off your meal plan. If you're trying to lose weight or curb your appetite, Fast Lean Pro can help. Supporting substances such as niacin and chromium contribute to this. The body can further benefit from these nutrients, such as through improved metabolic regulation. Fast lean Pro is non-GMO, vegan friendly, and contains no artificial ingredients or stimulants. Fast Lean Pro is a weight loss product that promotes the body's natural self-feeding process. The body naturally removes old, damaged cells through a process known as autophagy to encourage cell regeneration and repair. Recent studies by a group
Nathan Goodyear

Weekly Versus Monthly Testosterone Administration on Fast and Slow ... - PubMed - NCBI - 0 views

www.ncbi.nlm.nih.gov/...25387260

Testosterone muscle sarcopenia low T low Testosterone low T men male hormones

shared by Nathan Goodyear on 24 Nov 14 - No Cached
  • Nathan Goodyear on 24 Nov 14
     
    Weekly Testosterone injections increase type 1 slow muscle fibers more than type II fast twitch muscle fibers compared to monthly injections.  The study looked at older men with sarcopenia and low T.
Nathan Goodyear

Nature vs. nurture: can exercise really alter fiber type composition in human skeletal ... - 0 views

jap.physiology.org/...1591

muscle muscle fiber physiology

shared by Nathan Goodyear on 20 Mar 15 - No Cached
  • Nathan Goodyear on 20 Mar 15
     
    Muscle fiber types exist on a continuum.
Nathan Goodyear

Frontiers | Sarcopenia and Androgens: A Link between Pathology and Treatment | Endocrin... - 0 views

journal.frontiersin.org/...full

sarcopenia muscle loss

shared by Nathan Goodyear on 16 Apr 15 - No Cached
  • sarcopenia induces a change in the proportion of skeletal muscle fibers, inducing a shift from type II (fast) to type I (slow) fibers as well as preferential loss of type II fibers
  • testosterone stimulates protein synthesis by both a short-term mechanism-rapid activation of pre-existing components of the translational apparatus- and a long-term mechanism-increase in cell or tissue capacity at the protein synthesis level leading to increase in ribosome quantity
  • testosterone induces an increase in cross-sectional area (CSA) in type I and II muscle fibers and in myonuclear quantity, indicating that testosterone exerts more of a hypertrophic than a hyperplasic effect on skeletal muscle
  • Nathan Goodyear on 16 Apr 15
     
    good discussion of sarcopenia.
Nathan Goodyear

PLOS ONE: Overexpression of the Mitochondrial T3 Receptor p43 Induces a Shift in Skelet... - 0 views

www.plosone.org/...journal.pone.0002501

mitochondria T3 thyroid hormone hormones muscle PPAR-gamma PPAR PGC1-alpha

shared by Nathan Goodyear on 29 Jun 13 - No Cached
  • Nathan Goodyear on 29 Jun 13
     
    T3 induces beneficial oxidative changes in muscles through its interaction with mitochondrial receptors.  PGC-1alpha and PPAR-gamma were involved in this process.  The important point here is that T3 is increasing oxidative function of muscle through interaction with mitochondria.
Nathan Goodyear

The nutritional biochemistry of creatine - 0 views

www.jnutbio.com/...abstract

creatine sports performance exercise

shared by Nathan Goodyear on 27 Jan 14 - No Cached
  • Nathan Goodyear on 27 Jan 14
     
    Loading dose of creatine, 20 grams/day, over 5-6 days increases total muscle creatine levels.  This has been shown to improve athletic performance.  The phosphocreatine  in Type II muscle fibers are particularly increased.  This can be maintained at 2 grams/day.
Nathan Goodyear

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

jaha.ahajournals.org/...e000272

low T Testosterone cardiovascular disease CAD CHF insulin resistance type II diabetes diabetes obesity men male hormone hormones therapy

shared by Nathan Goodyear on 13 May 14 - No Cached
  • Nathan Goodyear on 13 May 14
     
    Some startling statistics in this 2013 review on Testosterone in men.  Studies reflect an inverse relationship between Testosterone and CAD severity.  That is, the lower the Testosterone levels, the increase in severity of CAD. This same association was also found with CHF.  Low Testosterone is common in those with CAD, CHF, type II diabetes, increased IMT in carotids and aorta, and obesity when compared to "healthy" individuals.  Testosterone therapy in those with CAD found benefits: prolongation of ST segment depression, coronary vasodilation, improved exercise capacity in those with CHF, shift to type I muscle fibers, shorten the QTc interval.  Testosterone therapy has been shown to improve insulin resistance, improve HgbA1c and decrease waist circumference and fat loss in obese individuals.  Otherwise, a good review of the association between a declining Testosterone and cardiovascular disease.
wheelchairindia9

Tynor Ankle Binder - 0 views

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

Get Happy Feet With The Right Walking Boots orthopedic walking boot boot type walkers decrease pain and edema comfort to the lower leg rocking motion of the foot boots provide support to the ankle

shared by wheelchairindia9 on 23 Mar 16 - No Cached
  • wheelchairindia9 on 23 Mar 16
     
    The boot type walkers can be provided in a fixed mode or with ankle joints to provide articulation. Pneumatic support is also available. The brace has a lightweight, durable, semi rigid shell that will support the limb and provide protection. Incorporated are medial and lateral uprights, heel and rocker sole. Closure is achieved with Velcro. The strapping system provides full circumferential compression of the limb. The breathable fiber liner is washable. The articulated boot allows range of motion (ROM) usually from approximately 20 degrees dorsiflexion to 40 degrees plantar flexion. Tynor Walker Boot is designed by the Tynor to rehabilitate the person after injury or fracture. It allows easy movement as well as supports the ankle and leg. This can be a great substitute for cast and also useful during early cast removal. It can also be used during sprain in the foot and this walker gives great relief to the pain. It can easily do any mild activity. It also works for the persons with a lower leg and will give an equal level of the lower feet as well as reduces the pressure. It effectively enclosed the muscles of the leg or foot during the fracture and gives comfort without disturbing the recovery process. This walker boot is made up from the good quality material. It has Aluminum lateral bars that are corrosion free. It is light in weight and provides enhanced mobility. It gives sturdy support to feet and leg. Its Hook Loop system allows to adjust it according to the comfort. It is also infused with Foam liner and Pad set that gives soft feet and also provides great support. It is available in different sizes. Tynor Walker Boot is designed for rehabilitation after injury, fracture , sprains or surgery of foot, ankle or lower leg. The boots provide support to the ankle and leg without inhibiting mobility. They can be a substitute for cast or can be used in case of early cast removal. With a wider rocker bottom, these boots promote a natural gait, reduced
Nathan Goodyear

Frontiers | Nitrate Intake Promotes Shift in Muscle Fiber Type Composition during Sprin... - 0 views

journal.frontiersin.org/...full

nitrates vegetables nutrition diet muscle training exercise athletes

shared by Nathan Goodyear on 10 Oct 16 - No Cached
  • Nathan Goodyear on 10 Oct 16
     
    Nitrates from greens aid in athletic training.
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