Treningsforum

en kamerat av meg i militæret hevder at en lege fortalte han at det ikke går ann å øke anntallet muskelceller i kroppen, bare at de man har fra før kan øke i størrelse, derav økt muskelvolum.
Jeg har alltid trodd at man kunne bygge nye muskelceller.
hva er riktig?
 ???

Nå skal ikke jeg være helt påståelig men jeg tror du blander litt sammen muskelceller og muskelfibre. Du kan ikke øke antall muskelfibre men volumet på muskelfibrene.

nei, jeg blander ikke. kompisen sa at man ikke kunne bygge fler muskelceller. at man er født med et visst anntall og at disse kun kan bli større, ikke flere...

Man kan ikke bygge flere muskelceller, bare øke størrelsen på de en allerede har.

muskelfibre= muskeceller ;)

Og kameraten din har rett - man kan ikke bygge mer muskelceller/ fibre, men de kan øke i volum, og ja antall muskelceller er medføtt samme som fettceller.

ok. takk for opplysningene.

Hver muskelfiber er bygget opp av mange myofibriller. Om jeg har forstått det riktig etter det jeg har lært innen faget "treningslære" så kan man øke antall myofibriller slik at muskelfiberen får et større tverrsnitt, som igjen gjør at muskelen ser større ut.

Jo, det er mulig:

"J Appl Physiol. 1993 Apr;74(4):1893-8.
"Title: Effects of anabolic steroids on the muscle cells of strength-trained athletes.

Researchers: Kadi F, Eriksson A, Holmner S, Thornell LE Department of Integrative Medical Biology, Umea University, Sweden.

Source: Med Sci Sports Exerc 1999 Nov;31(11):1528-34

Summary:

Athletes who use anabolic steroids get larger and stronger muscles. How this is reflected at the level of the muscle fibers has not yet been established and was the topic of this investigation. METHODS: Muscle biopsies were obtained from the trapezius muscles of high-level power lifters who have reported the use of anabolic steroids in high doses for several years and from high-level power lifters who have never used these drugs. Enzyme-immunohistochemical investigation was performed to assess muscle fiber types, fiber area, myonuclear number, frequency of satellite cells, and fibers expressing developmental protein isoforms.

RESULTS: The overall muscle fiber composition was the same in both groups. The mean area for each fiber type in the reported steroid users was larger than that in the nonsteroid users (P < 0.05). The number of myonuclei and the proportion of central nuclei were also significantly higher in the reported steroid users (P < 0.05). Likewise, the frequency of fibers expressing developmental protein isoforms was significantly higher in the reported steroid users group (P < 0.05). [these researchers found embryonic fiber development in the nonsteroid using group as well...just not as much as in the group using.]

CONCLUSION: Intake of anabolic steroids and strength-training induce an increase in muscle size by both hypertrophy and the formation of new muscle fibers (hyperplasia). We propose that activation of satellite cells is a key process and is enhanced by the steroid use. The incorporation of the satellite cells into preexisting fibers to maintain a constant nuclear to cytoplasmic ratio seems to be a fundamental mechanism for muscle fiber growth. Although all the subjects in this study have the same level of performance, the possibility of genetic differences between the two groups cannot be completely excluded."

Jeg tror ikke alle vil bruke anabole steroider for å få større muskler.. Det er juks, og det skal vi ikke ha noe av. Uten bruk av AS vil man ikke kunne få flere fibrer i en muskelbunt.

dette er sant jeg så på et bodybuilder-show (der folk går og briefer med kroppen sin) der viste de en bicept, bicepten var mange tråder. detsto mer du trener bicepten desto større blir disse trådene skjønner?

Ja nettopp. De blir større men ikke flere...

Poenget mitt var at denne legen tar feil.

Du har jo rett i forhold til dette. Det er mulig. Men det er tross alt mye som er mulig, om man vil ta i bruk det aller meste......  ::)

Konklusjonen blir vel at det uten noe "ekstra tilskudd" ikke er mulig ;)

Det står ikke at det ikke er mulig uten AAS.

Men heller ikke at det er mulig uten!!

Antar at dersom det hadde vært mulig, hadde det nok finnes et paper på det også vel ?

Det er ikke noe magisk som skjer når steroider tas i bruk. Muskeloppbygging foregår på samme måte, bare hurtigere og mer effektivt pga unaturlige hormonnivå. Det er derfor naturlig å anta at hyperplasia også er mulig uten AAS.

Kan jo hende at disse hormonnivåene er det som gjør at det kan vokse frem også vel ?? Så vidt jeg leser dette du la ut, er det ingenting som konkluderer med at det er AAS eller ikke. Altså er jeg litt enig, men egentlig umulig å si. Desverre...

Er det noen her som VET 100% sikkert som kan svare på dette?

Den artikkelen Lureper posten viser jo nettopp at man IKKE KAN VITE dette 100 %.

Får vel mer konkrete svar på det i fremtiden antar jeg.. Så man får mene hva man vil til den tid, selv om jeg mener det ikke er mulig da.. ;D

hyperplasia (flere muskelfibre) og hypertrofi (større eksisterende muskelfibre) har det de seneste årene vært forsket mye på. Det har enda ikke blitt bevist at hyperplasia kan forekomme.

når en muskel har vokst er det en kombinasjon av disse faktorene so har forekommet:

-økning i aktin filamenter

-økning i myosinfilamenter

-flere myofibriller

-større sarkoplasma

-mer bindevev

håper dette gjord ting noe klarere.. :)

Noe definitivt svar er vanskelig å gi, men jeg tror Ossie har oppsummert det viktigste. Jeg sakser fra en artikkel om temaet (første del av artikkelen).

Muscle Hypertrophy
Tetsuro Tamaki
Department of Physiology
Tokai University School of Medicine
Kanagawa, Japan

   Skeletal muscle hypertrophy is one of the adaptation mechanisms of the living system to the environment.  Muscle hypertrophy is observed in both skeletal muscle and cardiac muscle.  However, in this section, special attention is devoted to skeletal muscle hypertrophy.  It is generally accepted that mammalian skeletal muscle is enlarged  by exercise overloads and is reduced by disuse, as suggested by the famous words of Albert Szent-Gyorgyi "Living systems are worn out by inactivity and developed by use".  It is also recognized that the most popular method of inducing muscle hypertrophy and increased muscle strength is high-intensity, short-duration, progressive overload exercise such as weight-lifting.  This muscle hypertrophy is called exercise- or work-induced hypertrophy.  
   Muscle hypertrophy is a volumetrical change in muscle tissues covered by fascia, and may be observed within 2 or 3 months after the onset of training. Structural, neural and enzymatic adaptations of the muscle appear at this time.  
   The purpose of this section is to understand the physiological mechanisms of muscle hypertrophy including structural, neural and enzymatic adaptations.  In addition, various stimulations which result in various forms of muscle hypertrophy are discussed. Skeletal muscle is a tough, plastic and multiple tissue.

What Is The Muscle Hypertrophy ?

   Skeletal muscle is composed of muscle fibers, connective tissue surrounding muscle fibers, blood vessels and intra- and extracellular water, and all of these components are covered by fascia. These structure shows in Fig. 1.  Therefore, it is considered that increases in mass or volume of skeletal muscle are mainly caused by four factors as follows;  
• Transverse enlargement of individual fibers (increases in individual fiber cross-sectional area; muscle fiber hypertrophy).
• Increases in fiber number (formation of new muscle fiber; muscle fiber hyperplasia).
• Increases in connective tissues surrounding muscle fibers.
• Increases in extracellular water  

Muscle Fiber Hypertrophy

   The muscle fibers are enclosed in a membrane called the sarcolemma, and each muscle fiber contains many myofibrils which are arranged in parallel in the sarcoplasm.  Increases in existing individual fiber cross-sectional areas are brought about by increases in these myofibrils within the fibers, which is  of course, functionally significant. It enables the muscle to produce additional force because contractile proteins such as myosin and actin also increase and total muscle contraction force becomes higher.   For the increase in contractile proteins, protein  synthesis is necessary.  Protein synthesis and degradation always occur in the living cells, and they are regulated at the same rate to maintain the total protein concentration in the cells.  The muscle fiber hypertrophy described above arises from a net increase in the protein synthesis rate(protein synthesis / protein degradation) within the muscle cells, and increased synthesis of RNA (ribonucleic acid) occurs at the same time.  There is also an increase in the density or amount of ribosomal RNA polymerase, which lags behind the increase in RNA synthesis.   Little is known about the factors which affect the activity of RNA polymerase, but it is known that polyamines have the ability to stimulate RNA synthesis in vitro.  In any case, the increase in RNA appears to be an essential aspect of the hypertrophic process.

Muscle Fiber Hyperplasia

   It has generally been accepted that the number of muscle fibers does not change once embryonic differentiation of the tissue is complete.  The increase in girth of the muscle is therefore the result of existing muscle fiber hypertrophy as mentioned previously.  Recently, however, many findings have indicated that muscle enlargement following resistance training may be the result of an increase in both cross-sectional fiber area and an increase in fiber number.  The complete details of muscle fiber hyperplasia are dealt with in the essay, "Muscle Hyperplasia".

Increases In Connective Tissue Surrounding Muscle Fibers

   Connective tissue surrounding muscle fibers is mainly concerned with preservation of muscle structures and protection of muscle cells(fibers) rather than with the active function of the muscle.  Increases in connective tissue are usually observed in regenerating muscles after various muscle injuries induced by crushing, forced stretching, ischemia or anoxia of the muscle and in cases of myopathy such as muscular dystrophy.  However, they are also observed in cases of "stretch induced muscle hypertrophy " (described in detail later), after prolonged training mainly using eccentric contraction (forced stretching of near maximally  contracted muscle) and the extremely enlarged muscle of elite bodybuilders.  Active functional improvement of the muscle can not be expected in such cases.  It may be suggested that these muscles are affected by some repetitive damage, and connective tissue increases to protect the muscle cells(fibers).

Forrseten, jeg glemte å legge ved en link til en annen artikkel om samme tema (dette er som dere kan se av linken kontroversielt - men skal vi tro dette tro dette, var nok ikke Mike Mentzer helt borte).

http://home.hia.no/~stephens/hypplas.htm ::)

Igf-1 er det stoffet som trolig har evnen til å forårsake hyperplasi. Utover dette er det kun hypertrofi som er aktuelt.

Hvis IGF-1 er det stoffet(veksthormon) som kan forårsake hyperplasia og tung trening sammen med et skikkelig kosthold med riktige fettsyrer kan trigge produksjonen av dette hormonet så påstår jeg at kroppsbygging er en aktivitet som indirekte sørger for at hyperplasia finner sted ;D

Soje

Det er omdiskutert, men enno ikkje bevist/ motbevist, trur eg. Eg skal sjekke om eg finn nokre rapportar når eg gidder.

-Kven var det forresten som gav meg en honnør? Kunne vere kjekt å vite kva eg skreiv som var populært...-

Her er en rapport på CEM, lagt inn av Nandi12:

*****************
Med Sci Sports Exerc. 1999 Nov;31(11):1528-34.

Effects of anabolic steroids on the muscle cells of strength-trained athletes.

Kadi F, Eriksson A, Holmner S, Thornell LE.

Department of Integrative Medical Biology, Umea University, Sweden. Fawzi.Kadi@anatomy.umu.se

PURPOSE: Athletes who use anabolic steroids get larger and stronger muscles. How this is reflected at the level of the muscle fibers has not yet been established and was the topic of this investigation. METHODS: Muscle biopsies were obtained from the trapezius muscles of high-level power lifters who have reported the use of anabolic steroids in high doses for several years and from high-level power lifters who have never used these drugs. Enzyme-immunohistochemical investigation was performed to assess muscle fiber types, fiber area, myonuclear number, frequency of satellite cells, and fibers expressing developmental protein isoforms. RESULTS: The overall muscle fiber composition was the same in both groups. The mean area for each fiber type in the reported steroid users was larger than that in the nonsteroid users (P < 0.05). The number of myonuclei and the proportion of central nuclei were also significantly higher in the reported steroid users (P < 0.05). Likewise, the frequency of fibers expressing developmental protein isoforms was significantly higher in the reported steroid users group (P < 0.05). CONCLUSION: Intake of anabolic steroids and strength-training induce an increase in muscle size by both hypertrophy and the formation of new muscle fibers. We propose that activation of satellite cells is a key process and is enhanced by the steroid use. The incorporation of the satellite cells into preexisting fibers to maintain a constant nuclear to cytoplasmic ratio seems to be a fundamental mechanism for muscle fiber growth. Although all the subjects in this study have the same level of performance, the possibility of genetic differences between the two groups cannot be completely excluded.
*******************

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