Question:
In muscle modelling, how do I compute the width parameter?
I am working over different muscle models to compute muscle forces and most of them include the so-called "width" parameter, but it is not referenced ...
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I am working over different muscle models to compute muscle forces and most of them include the so-called "width" parameter, but it is not referenced how to compute it, nor its meaning, just a simple value on a table. I would appreciate any help on this.
By Francisco Romero
·
Universidad de Extremadura
Question:
Can anyone suggest references for fiber type distributions?
I am designing a study to investigate neuromuscular function in two different muscle groups in untrained individuals; one that is predominantly fast t...
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I am designing a study to investigate neuromuscular function in two different muscle groups in untrained individuals; one that is predominantly fast twitch, and one that is a similar mix of slow and fast twitch. The quadriceps seem to be a good option for latter, but struggling on the former. I have seen authors state that the Triceps Brachii are predominantly fast twitch but can't find many references specifically documenting this. Can any body recommend some good references documenting the mean +/- SD of fiber types of different muscle groups in untrained (not sedentry) humans? I appreciate SD will be fairly large for most muscles.
By Neale Tillin
·
University of Roehampton
Question:
Why does horse serum induce differentiation of C2C12 myoblasts better than FBS?
I currently use 2% HS to induce differentiation, as many people commonly do, and it works very well. What mechanistic quality of HS makes it better?
I currently use 2% HS to induce differentiation, as many people commonly do, and it works very well. What mechanistic quality of HS makes it better?
By Nicholas Hatch
·
University of California, Los Angeles
Question:
Coupling molecular signals to physiological output measures - is discordance a sign of redundancy or does it serve a function?
Molecular signalling is often used as a surrogate measure for various outputs like glucose uptake and protein synthesis. However in the case of gluocs...
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Molecular signalling is often used as a surrogate measure for various outputs like glucose uptake and protein synthesis. However in the case of gluocse uptake only 30% of maximal PKB activity is required to saturate GLUT4 translocation (Bilan et al, 2009 - attached). In the case of protein synthesis, 30% of maximal S6K1 phosphorylation associates with saturated protein synthesis (Crozier et al, 2005 http://jn.nutrition.org/content/135/3/376.long). These data suggest that there is a reserve capacity built into signalling pathways. This raises the question "is this reserve capacity important and physiologically relevant?"
In feeding induced time course studies S6K1 switch off occurs more slowly than the switch off of protein synthesis (Atherton et al, http://ajcn.nutrition.org/content/92/5/1080.long) and in response to intermittent protein feeding the S6K1 phosphorylation response does not correlate with protein synthesis (Areta et al, 2013 http://www.ncbi.nlm.nih.gov/pubmed/23459753). Despite the lack of correlation between S6K1 and protein synthesis in response to feeding, the S6K1 response to resistance exericse correlates highly with hypertrophy in response to training (Baar and Esser, 1999 and Terzis et al, 2008) suggesting that it is a good read out of growth. What is the function of the residual S6K1 activity and why isn't there a correlation between S6K1 and feeding induced protein synthesis? Is this a feedforward mechanism?
How do we begin to reconcile the discordant data and do we need to develop new theories and methods to assess the molecular control of muslce metabolism and growth?
By David Hamilton
·
University of Stirling
Question:
Open
Does anyone know of studies that have investigated the mechanism(s) of myoglobin oxygenation?
Struggling to find literature investigating the mechanism(s) behind myoglobin oxygenation
Struggling to find literature investigating the mechanism(s) behind myoglobin oxygenation
By Taylor Thurston
·
California State University, Fullerton
Question:
Does anyone have references regarding series and parallel elastic components and countermovement jump height?
In particular, length-tension relationship and the utilization of elastic/strain energy.
In particular, length-tension relationship and the utilization of elastic/strain energy.
By Josh Conlon
·
University of Wisconsin - Milwaukee
Question:
What is the best way to perform non linear curve regression on sigmaplot?
I am attempting to attain mean response times, time constants and the amplitude of vo2kinetics data, and i have sigmaplot however am struggling to gai...
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I am attempting to attain mean response times, time constants and the amplitude of vo2kinetics data, and i have sigmaplot however am struggling to gain results as i have never used the software before.
By Danny Egleton
·
University of Bedfordshire
Question:
At what age does the process of sarcopenia start?
Research is mixed; most say third or fourth decades...
Research is mixed; most say third or fourth decades...
By Alex Munro
·
Newcastle University
Question:
Resistance exercise and the hormonal Ghost.
Recent work from the Phillips lab has shown that the hormonal response to resistance exercise plays little role in either the acute protein synthesis,...
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Recent work from the Phillips lab has shown that the hormonal response to resistance exercise plays little role in either the acute protein synthesis, signalling or the hypertrophy response to resistance exericse. Additionally a number of studies have brought into question the role of IGF-1 signalling in response to resistance exercise adaptations. However, these hormonal responses to resistance exercise are real and robust - so if they don't impact upon resistance exercise adaptations, what have they evolved to do?
By David Hamilton
·
University of Stirling
Question:
What is the easiest way to roughly estimate muscle forces?
Inverse dynamics are quite complicate and time consuming. So I would prefer for a rough estimation a method using EMG and perhaps cross section determ...
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Inverse dynamics are quite complicate and time consuming. So I would prefer for a rough estimation a method using EMG and perhaps cross section determination using MRI. Any suggestions?
By Lutz Dürselen
·
Universität Ulm
Question:
Does anybody have experience how to measure a muscle at work?
For my further research I need to measure a muscle work. The purpose of my research is to measure the activity of muscles while riding a canoe C1.
Tha...
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For my further research I need to measure a muscle work. The purpose of my research is to measure the activity of muscles while riding a canoe C1.
Thank you for response
Radim Sryncl
By Radim Stryncl
·
FTVS Prague
Question:
Relationship between muscle force and calcium influx in skeletal muscle excitation-contraction coupling
Is force strictly determined by muscle cell calcium alone? Can the same muscle force be achieved with different intracellular calcium concentrations? ...
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Is force strictly determined by muscle cell calcium alone? Can the same muscle force be achieved with different intracellular calcium concentrations? I don't mean long term changes in muscle structure, of course. For example, dantrolene reduces calcium efflux from the sarcoplasmic reticulum and reduces grip strength in mice. Does a 20% reduction in peak force mean a 20% reduction in intracellular peak calcium? Can the same force be achieved with different calcium concentrations? If there are other factors, what are they? Can anyone recommend an article discussing such quantitative aspects?
By Alexander Wolf
·
Nippon Medical School
