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1.  Exercise Physiology versus Inactivity Physiology: An Essential Concept for Understanding Lipoprotein Lipase Regulation 
Some health-related proteins such as lipoprotein lipase may be regulated by qualitatively different processes over the physical activity continuum, sometimes with very high sensitivity to inactivity. The most powerful process known to regulate lipoprotein lipase protein and activity in muscle capillaries may be initiated by inhibitory signals during physical inactivity, independent of changes in lipoprotein lipase messenger RNA.
PMCID: PMC4312662  PMID: 15604935
dose response; coronary heart disease (CHD); transcription; posttranslational; signaling; sedentary; aging
2.  Exercise, Stress Resistance, and Central Serotonergic Systems 
Voluntary exercise reduces the incidence of stress-related psychiatric disorders in humans and prevents serotonin-dependent behavioral consequences of stress in rodents. Evidence reviewed herein is consistent with the hypothesis that exercise increases stress resistance by producing neuroplasticity at multiple sites of the central serotonergic system, which all help to limit the behavioral impact of acute increases in serotonin during stressor exposure.
PMCID: PMC4303035  PMID: 21508844
wheel running; learned helplessness; anxiety; depression; prefrontal cortex; dorsal raphe nucleus
3.  Electron Paramagnetic Resonance Resolves Effects of Oxidative Stress on Muscle Proteins 
We have used site-directed spin labeling and electron paramagnetic resonance (EPR) to explore the effects of oxidation on muscle function, with particular focus on the actin-myosin interaction. EPR measurements show that aging or oxidative modification cause a decrease in the fraction of myosins in the strong-binding state, which can be traced to the actin-binding cleft of the myosin catalytic domain.
PMCID: PMC3934098  PMID: 24188980
myosin; actin; muscle; Reactive Oxygen Species (ROS); methionine; aging
4.  MRI reveals brain abnormalities in drug-naïve Parkinson’s disease 
Exercise and sport sciences reviews  2014;42(1):10.1249/JES.0000000000000003.
Most brain studies of Parkinson’s disease (PD) focus on patients who are already taking anti-parkinsonian medication. This makes it difficult to isolate the effects of disease from those of treatment. We review MRI evidence supporting the hypothesis that early-stage, untreated PD patients have structural and functional abnormalities in the brain, some of which are related to motor symptoms.
PMCID: PMC3885158  PMID: 24188978
diffusion tensor imaging (DTI); functional magnetic resonance imaging (fMRI); parkinsonism; grip force; subtype; de novo; movement
5.  The Effects of Practice on Coordination 
We review practice-induced changes in two variance components defined based on the uncontrolled manifold hypothesis: One of them affects task performance while the other one does not. Practice leads to a drop in the former component (higher accuracy), while the latter can drop, stay unchanged, or even increase. The last scenario can be achieved with practice that challenges performance stability.
PMCID: PMC3897239  PMID: 24188981
Synergy; practice; variability; redundancy; abundance
6.  Exercise and nutrition to target protein synthesis impairments in aging skeletal muscle 
The loss of skeletal muscle size and function with aging, sarcopenia, may be related, in part, to an age-related muscle protein synthesis impairment. In this review, we discuss to what extent aging affects skeletal muscle protein synthesis and how nutrition and exercise can be strategically employed to overcome age-related protein synthesis impairments and slow the progression of sarcopenia.
PMCID: PMC3790587  PMID: 23873131
Aging; Sarcopenia; Exercise; Protein; Insulin; Muscle Protein Synthesis; mTORC1
7.  How tendons buffer energy dissipation by muscle 
Exercise and sport sciences reviews  2013;41(4):10.1097/JES.0b013e3182a4e6d5.
To decelerate the body and limbs, muscles actively lengthen to dissipate energy. During rapid energy-dissipating events, tendons buffer the work done on muscle by temporarily storing elastic energy, then releasing this energy to do work on the muscle. This elastic mechanism may reduce the risk of muscle damage by reducing peak forces and lengthening rates of active muscle.
PMCID: PMC3836820  PMID: 23873133
Muscle; tendon; elastic energy; energy dissipation; deceleration
8.  Early Exercise Rehabilitation of Muscle Weakness in Acute Respiratory Failure Patients 
Acute Respiratory Failure patients experience significant muscle weakness which contributes to prolonged hospitalization and functional impairments post-hospital discharge. Based on our previous work, we hypothesize that an exercise intervention initiated early in the intensive care unit aimed at improving skeletal muscle strength could decrease hospital stay and attenuate the deconditioning and skeletal muscle weakness experienced by these patients.
Early exercise has the potential to decrease hospital length of stay and improve function in Acute Respiratory Failure patients.
PMCID: PMC3792856  PMID: 23873130
Length of Stay; Physical Function; Mobility; Intensive Care Unit; Strength Training
9.  Circadian Rhythms, skeletal muscle molecular clocks and exercise 
Exercise and sport sciences reviews  2013;41(4):10.1097/JES.0b013e3182a58a70.
Skeletal muscle comprises approximately 40 % of total body mass and, as such, contributes to maintenance of human health. In this review we will discuss the current state of knowledge regarding the role of molecular clocks in skeletal muscle. In addition we discuss a new function for exercise as a time setting cue for muscle and other peripheral tissues.
PMCID: PMC3866019  PMID: 23917214
circadian; skeletal muscle; exercise; peripheral tissues; zeitgeber
10.  Myofilament Protein Alterations Promote Physical Disability in Aging and Disease 
Skeletal muscle contractile function declines with age and age-associated diseases. Although muscle atrophy undoubtedly contributes to this decrease, recent findings suggest that reduced myofilament protein content and function also may participate. Based on these data, we propose that age- and disease-related alterations in myofilament proteins represent one molecular mechanism contributing to the development of physical disability.
PMCID: PMC4171103  PMID: 23392279
myosin; actin; muscle; human; fiber; molecular
11.  The Mechanistic Connection Between the Trunk, Knee, and Anterior Cruciate Ligament Injury 
Neuromuscular control of the trunk and knee predicts anterior cruciate ligament injury risk with high sensitivity and specificity. These predictors are linked, as lateral trunk positioning creates high knee abduction torque (load). The hypotheses explored are that lateral trunk motion increases load and that neuromuscular training that increases trunk control will decrease load.
PMCID: PMC4168968  PMID: 21799427
knee injury; high risk biomechanics; ACL injury prevention; neuromuscular control; female sports injuries; identification of knee injury risk factors
12.  Unraveling the complexities of SIRT1-mediated mitochondrial regulation in skeletal muscle 
SIRT1 is a purported central regulator of skeletal muscle mitochondrial biogenesis. Herein we discuss our recent work utilizing conditional mouse models, which highlight the complexities of SIRT1 biology in vivo, and question its role in regulating mitochondrial function and mitochondrial adaptions to endurance exercise. Further, we discuss the possible contribution of proposed SIRT1 substrates to muscle mitochondrial biogenesis.
PMCID: PMC3707796  PMID: 23792490
Exercise; sirtuins; acetylation; transcription; adaptation
13.  Insulin and Contraction-induced GLUT4 Traffic in Muscle: Insights from a Novel Imaging Approach 
Insulin and contraction-mediated glucose transporter 4 (GLUT4) trafficking have different kinetics in mature skeletal muscle. Intravital imaging indicates that insulin-stimulated GLUT4 trafficking differs between t-tubules and sarcolemma. In contrast, contraction-induced GLUT4 trafficking does not differ between membrane surfaces. This distinction is likely due to differences in the underlying signaling pathways regulating GLUT4 vesicle depletion, GLUT4 membrane fusion and GLUT4 re-internalization.
PMCID: PMC3602324  PMID: 23072821
Living mice; Intravital; In-Vivo; PI3-Kinase; AMP-Kinase; LKB1
14.  Task-Dependent Postural Control Throughout The Lifespan 
Routine activities performed while standing and walking require the ability to appropriately and continuously modulate postural movements as a function of a concurrent task. Changes in task-dependent postural control contribute to the emergence, maturation, and decline of complex motor skills and stability throughout the lifespan.
PMCID: PMC3608710  PMID: 23364347
Postural Control; Stability; Lifespan Development; Multi-task behavior; Mobility; Load Handling; Adaptive Locomotion
15.  Slowed Reaction Time During Exercise: What is the Mechanism? 
PMCID: PMC3661292  PMID: 23392281
16.  Measuring protein synthesis with SUnSET: a valid alternative to traditional techniques? 
Protein synthesis rates are commonly measured by using isotopic tracers to quantify the incorporation of a labelled amino acid into muscle proteins. Here we provide evidence supporting our hypothesis that the non-isotopic SUnSET technique is a valid and accurate method for the measurement of in vivo changes in protein synthesis at the whole muscle and single muscle fiber levels.
PMCID: PMC3951011  PMID: 23089927
skeletal muscle; translation; hypertrophy; atrophy; puromycin; muscle fiber type; myosin heavy chain
17.  The Importance of Pre and Postoperative Physical Activity Counseling in Bariatric Surgery 
There is increasing evidence that physical activity (PA) can enhance weight loss and other outcomes after bariatric surgery. However, most preoperative patients are insufficiently active, and without support, fail to make substantial increases in their PA postoperatively. This review provides the rationale for PA counseling in bariatric surgery and describes how to appropriately tailor strategies to pre- and postoperative patients.
PMCID: PMC3529741  PMID: 22710705
exercise; severe obesity; treatment; clinical care; gastric bypass; laparoscopic adjustable gastric band
18.  Exercise Ventilatory Limitation: The Role Of Expiratory Flow Limitation 
Ventilatory limitation to exercise remains an important unresolved clinical issue; as a result, many individuals misinterpret the effects of expiratory flow limitation as an all-or-nothing phenomenon. Expiratory flow limitation is not all-or-none; approaching maximal expiratory flow can have important effects not only on ventilatory capacity but also on breathing mechanics, ventilatory control, and possibly exertional dyspnea and exercise intolerance.
PMCID: PMC3529766  PMID: 23038244
dynamic compression of the airways; maximal expiratory flow; breathing mechanics; ventilatory limitations to exercise; ventilatory limitations; ventilatory constraints; cardiopulmonary exercise testing
19.  Mobility decline in old age: A time to intervene 
PMCID: PMC3530168  PMID: 23262463
20.  Are there Race-Dependent Endothelial Cell Responses to Exercise? 
African Americans have endothelial dysfunction which likely contributes to their high prevalence of hypertension. Endothelial cell responses to stimuli could play a role in the development of endothelial dysfunction and hypertension. High physiological levels of vascular laminar shear stress can profoundly alter endothelial cell phenotype. It is not known whether there are race-dependent endothelial cell responses to laminar shear stress.
PMCID: PMC3577070  PMID: 23262464
Endothelial cell; shear stress; exercise; African American; oxidative stress; inflammation
21.  Basal and exercise-induced regulation of skeletal muscle capillarization 
Exercise and sport sciences reviews  2009;37(2):10.1097/JES.0b013e31819c2e9b.
Regulation of skeletal muscle capillarization involves distinct signaling pathways and growth factors including nitric oxide and vascular endothelial growth factor. Our understanding of this complex regulation continues to expand with the identification of new angiogenic growth factors. Future work needs to increase the use of advanced molecular techniques to expand our knowledge of the regulation of basal and exercise-induced capillarization.
PMCID: PMC3836628  PMID: 19305200
capillaries; exercise; mitochondria; muscle fiber size; VEGF; nitric oxide; 5′-AMP activated protein kinase
22.  A Role for Myokines in Muscle-Bone Interactions 
This review presents the hypothesis that muscle is a source of secreted factors (myokines) that can influence bone mass in both positive and negative ways. Growth factor secretion by muscle may therefore be one pathway through which mechanical signals are transduced biologically.
PMCID: PMC3791922  PMID: 21088601
IGF-1; FGF-2; Myostatin; periosteum; muscle injury
23.  Severe Obesity: Evidence for a Deranged Metabolic Program in Skeletal Muscle? 
Severe obesity is increasing at a disproportionate rate compared to milder grade obesity. Our research group has obtained evidence indicative of an “obesity metabolic program” in the skeletal muscle of severely obese individuals which may be genetically or epigenetically determined. We believe this represents a paradigm shift in thinking about metabolic regulation in obesity.
PMCID: PMC3458185  PMID: 22710702
Bariatric surgery; Exercise training; Fat oxidation; Class III obesity; Insulin action; Mitochondria; Obesity
24.  Effect of Statins on Skeletal Muscle: Exercise, Myopathy, and Muscle Outcomes 
Statins are effective for reducing low-density lipoprotein cholesterol and cardiac events, but can produce muscle side effects. We have hypothesized that statin-related muscle complaints are exacerbated by exercise and influenced by factors including mitochondrial dysfunction, membrane disruption and/or calcium handling. The interaction between statins, exercise and muscle symptoms may be more effectively diagnosed and treated as rigorous scientific studies accumulate.
PMCID: PMC3463373  PMID: 23000957
cholesterol-lowering medication; muscle strength; aerobic capacity; myalgia; Vitamin D; HMG CoA Reductase Inhibitor
25.  Altered Mechanisms of Thermoregulatory Vasoconstriction in Aged Human Skin 
Human exposure to cold stimulates cutaneous vasoconstriction by activating both sympathetic reflex and locally mediated pathways. Older humans are vulnerable to hypothermia because primary aging impairs thermoregulatory cutaneous vasoconstriction. This article highlights recent findings discussing how age-related decrements in sympathetic neurotransmission contribute directly to thermoregulatory impairment, whereas changes in local cold-induced intracellular signaling suggest a more generalized age-associated vascular dysfunction.
PMCID: PMC3756318  PMID: 18580292
skin blood flow; aging; temperature regulation; adrenergic; Rho kinase; cold

Results 1-25 (70)