Fredrik's studiehjørne

[Sondre Aalbotsjord]

Hva mener du med 'overskuddsprotein'?

Uansett; Termodynamikkens første hovedsetning forklarer at energi kan aldri oppstå og aldri tilintetgjøres, men kan kun gå over i andre former. Dette gjelder også i kroppen vår - Energi/kalorier kan ikke 'forsvinne'.

Overskuddsprotein som i protein som kroppen ikke bruker til proteinsyntesen.

Jeg vet det angående Glukoneogenese men jeg har vanskeligheter for å finne studier angående dette.

Når jeg diskuterer med dvs folk med utdannelser innen dette så er det jo alltid finfint å ha studier som backer opp det jeg sier.

Har søkt rundt på pubmed men jeg finner ikke noe angående dette.

[Fredrik Gyllensten]

Overskuddsprotein som i protein som kroppen ikke bruker til proteinsyntesen.

Jeg vet det angående Glukoneogenese men jeg har vanskeligheter for å finne studier angående dette.

Når jeg diskuterer med dvs folk med utdannelser innen dette så er det jo alltid finfint å ha studier som backer opp det jeg sier.

Har søkt rundt på pubmed men jeg finner ikke noe angående dette.

Kort forklart: Proteiner som ikke blir brukt til proteinsyntese blir lagret som glukose.

Lyle McDonald har skrevet litt om dette her: Excess Protein and Fat Storage - Q&A | BodyRecomposition - The Home of Lyle McDonald

[Sondre Aalbotsjord]

Kort forklart: Proteiner som ikke blir brukt til proteinsyntese blir lagret som glukose.

Lyle McDonald har skrevet litt om dette her: Excess Protein and Fat Storage - Q&A | BodyRecomposition - The Home of Lyle McDonald

Lyle Mcdonald... Hvorfor tenkte jeg ikke på han.

Tusen takk

[Fredrik Gyllensten]

HVA ER STIMULI FOR MUSKELVEKST? OPPSUMMERING AV KAPITTEL 4 I Styrketrening - i teori og praksis (Raastad, T. m.fl.)

- Oppsummering: "Et stort mekanisk drag i muskelaturen ser ut til å være en av de viktigste stimuliene for de prosessene som leder til hypertrofi i muskelaturen som belastes ved styrketrening. Både størrelsen på det mekaniske draget (hvor tungt vi løfter) og tiden dette draget varer (hvor mange repetisjoner og serier vi gjør) påvirker størrelsen på signalet til muskelvekst. I tillegg er det metabolske stresset i muskelcellene en viktig stimulus for muskelvekst. Vi vet i dag at økt metabolsk stress, som ved redusert bodtilførsel til den muskelen som arbeider, i stor grad kan kompensere for suboptimalt mekanisk drag. Treningsprotokoller som gir både et stort mekanisk drag, og som gir et metabolsk stress, er derfor gode protokoller å følge hvis muskelvekst er hovedmålet med styrketreningen.

Ulike styrketreningsprotokoller påvirker akutte endringer i konsentrasjonen av viktige hormoner som testosteron, kortisol og GH forskjellig. Det ser imidlertid ikke ut til at de akutte endringene i blodkonsentrasjonen av disse hormonene under styrketreningsøktene er av avgjørende betydning for stimulering til muskelvekst. Det er i første rekke de lokale påvirkningen som skjer i den belastende muskelaturen som har betydning.

De prosessene som settes igang under en treningsøkt som involverer et stor mekanisk drag og/eller et stort metabolsk stess, involverer aktivering av lokale vekstfaktorer som IGF-1 (MGF), HGF og FGF, nedreguelring av myostatin og igangsetting av en rekke intracellulære prosesser som regulerer både den generelle translasjonshastigheten og mer spesifikt transkripsjonen av bestemte gener involvert i hypertrofiprosessen. Disse signalene går både i muskelfibrene og parallelt i satelittceller, slik at et økt antall aktiverte satelittceller etter hvert bidrar med flere cellekjerner til de muskelfibrene som øker i volum. På denne måten økes kapasiteten til proteinsyntese i takt med at muskelfibrene vokser i størrelse. Selv om de akutte endringene skjer i viktige hormoner under en styrketreningsøkt, ikke ser ut til å spille en viktig rolle for muskelveksten, så vil endringer i de basale nivåene av testosteron, kortisol, GH og insulin kunne påvirke vår totale muskelmasse i en treningsperiode. Generelt vil et godt kosthold og en fornuftig kontrollert treningsbelastning være de viktigte faktorene som påvirker basalnivåene av disse hormonene. Kostholdets betydning er nærmere beskrevet i kapittel 17."

* Referanser: s. 105-106: Ref. 1-92, Kapittel 4, Styrketrening - i teori og praksis (Raastad, T. m.fl.).

[Fredrik Gyllensten]

ET PAR SPESIELLE STUDIER RUNDT SEX ETC. - KOS DERE

En studie fra 2004 undersøkte korrelasjonen mellom antall ejakulasjoner/utløsninger både gjennom sex og masturbasjon, og risiko for prostatakreft/prostate cancer. Det var totalt sett ingen statisstisk betydelig assosiasjon i de fleste kategoriene av ejakulasjoner, men høy frekvens var assosiert med en senket risiko for prostatakreft; "...The multivariate relative risks for men reporting 21 or more ejaculations per month compared with men reporting 4 to 7 ejaculations per month at ages 20 to 29 years were 0.89 (95% confidence interval [CI], 0.73-1.10); ages 40 to 49 years, 0.68 (95% CI, 0.53-0.86); previous year, 0.49 (95% CI, 0.27-0.88); and averaged across a lifetime, 0.67 (95% CI, 0.51-0.89)..."

* Leitzmann MF, Platz EA, Stampfer MJ, Willett WC, Giovannucci E. Ejaculation frequency and subsequent risk of prostate cancer. JAMA. 2004 Apr 7;291(13):1578-86. Pubmed.

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En studie fra desember 2010 undersøkte testosteron-nivåene hos menn ved en Sex Club i USA, og fant en betydelig økning på 36 % i menn etter besøket. Økningen var større hos de som deltok i seksuell aktivitet (72 %) sammenlignet med de som kun observerte (11 %). (notater: anabole hormoner, seksualitet, pornografi)

* Escasa MJ, Casey JF, Gray PB. Salivary Testosterone Levels in Men at a U.S. Sex Club. Arch Sex Behav. 2010 Dec 17. [Epub ahead of print]. Pubmed.

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Forskning viser at fargen rød kan øke hastighet/kraft og styrke av reksjoner (1), samt ha en rekke andre effekter; blant annet utpsyking av konkurrenter (2), og røde klær kan oppfattes mer attraktivt av det motsatte skjønn (3, 4). (notater: red, attraktivitet, pen, sex, power, utseende).

* prnewswire.com; Color Red Increases the Speed and Strength of Reactions.

1) Elliot AJ, Aarts H. Perception of the color red enhances the force and velocity of motor output. Emotion. 2011 Apr;11(2):445-9. Pubmed.

2) Feltman R, Elliot AJ. The influence of red on perceptions of relative dominance and threat in a competitive context. J Sport Exerc Psychol. 2011 Apr;33(2):308-14. Pubmed.

3) Elliot AJ, Niesta D. Romantic red: red enhances men's attraction to women. J Pers Soc Psychol. 2008 Nov;95(5):1150-64.Pubmed.

4) Elliot AJ, Kayser DN, Greitemeyer T, Lichtenfeld S, Gramzow RH, Maier MA, Liu H. Red, rank, and romance in women viewing men. J Exp Psychol Gen. 2010 Aug;139(3):399-417. Pubmed.

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En studie fra januar 2011 fant at å lukte på kvinners tårer reduserer selv-rapportert seksuell opphisselse, fysiologiske målinger av opphisselse, og testosteron nivåer. (notater: hormoner, testosterone, sex).

* Mens Health.

Gelstein S et al. Human tears contain a chemosignal. Science. 2011 Jan 14;331(6014):226-30. Epub 2011 Jan 6. Pubmed.

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[Gjest Jester]

Apropos: forskning.no > Et napp for helsa

[M. M]

Syntes denne var interessant. Ikke en studie i seg selv, men henviser til noen. Nutrient Timing Endures: Circadian Rhythm Protein Timing

[Fredrik Gyllensten]

En studie fra oktober 2010 sammenlignet effekten av periodisk energirestriksjon med kuntinuerlig energirestriksjon, og dets effekter på vekttap og risikofaktorer for metabolsk sykdom. Studien fant et periodisk energirestriksjon og kontinuerlig kalorirestriksjon var like effektive på de fleste punkter, men overraskende nok var kontinuerlig restriksjon bedre likt av deltakerne; flere rapporterte at de ville fortsette dietten etter studien (85 % vs. 58 %), og færre rapporterte bivirkninger og ukomfortable fysiske og psykologiske effekter. (Notater: slanking, vekttap, periodisk kaloriunderskudd, kontinuerlig kaloriunderskudd, intermittent energy restriction (IER), continuous energy restriction (CER).)

* Referanser: Alan Aragon -> aarr-Feb_2011.pdf.

Harvie MN, et al. The effects of intermittent or continuous energy restriction on weight loss and metabolic disease risk markers: a randomized trial in young overweight women. Int J Obes (Lond). 2010 Oct 5. [Epub ahead of print] [Medline]

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Aspartame, Stevia, and Appetite: En studie fra august 2010 (1) så på effektene fra søtstoffene aspartam/aspartame og stevia, sammenlignet med sukrose/sucrose, og dets effekt på appetitt/metthetsfølelse/satiety. Personene som fikk stevia eller aspartam hadde et betydelig lavere kaloriinntak enn sukrose-gruppen, som kan forklares med det økte kaloriiinnholdet i sukrose-gruppen. Studien viser ikke noen korrelasjon mellom søtstoff og økt sultfølelse. Det er dog limitasjoner; dette var en korttidsstudie, og det kan tenkes at høyt bruk av søtstoffer over lang tid kan ha andre effekter.

James Krieger:

- A recent study indicates that non-caloric sweeteners like aspartame and stevia do not stimulate appetite over the short term. However, questions remain about heavy long-term consumption over many years. As with many things, moderation is important.

- Points of Interest

-- Subjects consumed a preload of tea and crackers with cream cheese that was sweetened with aspartame, stevia, or table sugar. They were then provided a lunch and a buffet dinner.

-- Subjects consumed more calories over the day when consuming sugar versus the non-caloric sweeteners. The extra calories were solely due to the added sugar

- Quotes

-- "This study does not support the idea that non-caloric sweeteners like aspartame stimulate appetite."

-- "The study was short-term, lasting only a day."

-- ...a lot of questions remain over whether artificial sweeteners could promote increased calorie intake over extremely long periods of time (i.e., years). If they do, it is likely only when consumed in large amounts."

* Referanser: James Krieger.

1) Anton, S.D., et al. Effects of stevia, aspartame, and sucrose on food intake, satiety, and postprandial glucose and insulin levels. Appetite. 55(1):37-43, 2010.

SECONDARY REFERENCES

- Fowler, S.P., et al. Fueling the obesity epidemic? Artificially sweetened beverage use and long-term weight gain. Obesity. 16(8):1894-1900, 2008.

- Gosnell, B.A., et al. Food presentation and energy intake in a feeding laboratory study of subjects with binge eating disorder. Int J Eat Disord. 30(4):441-446, 2001.

- Kissileff, H.R., et al. A quadratic equation adequately describes the cumulative food intake curve in man. Appetite. 3(3):255-272, 1982.

- Raben, A., et al. Sucrose compared with artificial sweeteners: different effects on ad libitum food intake and body weight after 10 wk of supplementation in overweight subjects. Am J Clin Nutr. 76(4):721-729, 2002.

- Swithers, E., and T.L. Davidson. A role for sweet taste: calorie predictive relations in energy regulation by rats. Behav Neurosci. 122(1):161-173, 2008.

- Yang, Q. Gain weight by “going diet?” Artificial sweeteners and the neurobiology of sugar cravings: Neuroscience 2010. Yale J Biol Med. 83(2):101-108, 2010.

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[Fredrik Gyllensten]

Studie 1: Mye alkohol er ikke bra, litt kan funke:

Alcohol and Body Weight: Lavt til moderat inntak av alkohol er assosiert med lavere kroppsvekt, mens høyt inntak (30+ g/d) er assosiert med høyere kroppsvekt. Alkohol før et måltid er også vist å øke kaloriinntaket fra måltider, og det er ikke kompansert for i neste måltid.

"- Article Summary: Light to moderate alcohol intake (1-2 drinks per day maximum) can be a part of any effective weight management program, as long as you are mindful of your calorie intake. Also, it is better to consume alcohol with a meal than before a meal to avoid any potential appetite stimulatory effects.

- Points of Interest:

-- Alcohol does inhibit fat burning during its metabolism, but does not affect fat balance over 24 hours if you do not consume more calories than you are burning

-- Alcohol only causes weight gain when consumed in excess of calorie needs

-- Moderate amounts of alcohol (10% of calories) does not impair weight loss

-- 24 or more grams of alcohol (2 or more drinks) may stimulate appetite if consumed before meals, but there does not appear to be any effect on appetite when consumed with a meal

- Quotes

-- "…individuals who believe this are making the same mistake that believers in the carbohydrate/insulin hypothesis of obesity make."

-- "…alcohol has a fat-sparing effect similar to that of carbohydrate and will only cause fat gain when consumed in excess of normal energy needs."

-- "The men consumed significantly more food at the buffet after having the alcoholic lager compared to the other conditions."

* Referanser: James Krieger.

1) Caton, S.J., et al. Dose-dependent effects of alcohol on appetite and food intake. Physiol Behav. 81(1):51-58, 2004.

2) Cordain, L., et al. Influence of moderate daily wine consumption on body weight regulation and metabolism in healthy free-living males. J Am Coll Nutr. 16(2):134-139, 1997.

3) Cordain, L., et al. Influence of moderate chronic wine consumption on insulin sensitivity and other correlates of syndrome X in moderately obese women. Metabolism. 49(11):1473-1478, 2000.

4) Flechtner-Mors, M., et al. Effects of moderate consumption of white wine on weight loss in overweight and obese subjects. Int J Obes Relat Metab Disord. 28(11):1420-1426, 2004.

5) Hetherington, M.M., et al. Stimulation of appetite by alcohol. Physiol Behav. 74(3):283-289, 2001.

6) Koh-Banerjee, P., et al. Prospective study of the association of changes in dietary intake, physical activity, alcohol consumption, and smoking with 9-y gain in waist circumference among 16 587 US men. Am J Clin Nutr. 78(4):719-727, 2003.

7) Mukamal, K.J., et al. Roles of drinking pattern and type of alcohol consumed in coronary heart disease in men. N Engl J Med. 348(2):109-118, 2003.

8) Raben, A., et al. Meals with similar energy densities but rich in protein, fat, carbohydrate, or alcohol have different effects on energy expenditure and substrate metabolism but not appetite and energy intake. Am J Clin Nutr. 77(1):91-100, 2003.

9) Sonko, B.J., et al. Effect of alcohol on postmeal fat storage. Am J Clin Nutr. 59(3):619-625, 1994.

10) Wannamethee, S.G., and A.G. Shaper. Alcohol, body weight, and weight gain in middle-aged men. Am J Clin Nutr. 77(5):1312-1317, 2003.

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Studie 2: Light-produkter "funker":

En Studie Fra Juli 2011 sammenlignet en diett med matvarer med naturlig sukrose og en diett med 'diet' produkter søtet med kunstige søtningsmidler/kusntig søtstoff. En rekke helsemarkører var betydelig dårligere i sukrose-gruppen etter 10 uker, men deres kaloriinntak var også 32 % høyere, og mens søtstoff-gruppen mistet 1,5 kg, så økte sukrose-gruppen med 1,4 kg - dette kan sannsynligvis forklare de forskjellige resultatene. (notat: Kunstig søtstoff vs. sukker)

* Referanser: Alan Aragon - aarr.jul..2011....pdf

Raben A, Møller BK, Flint A, Vasilaris TH, Christina Møller A, Juul Holst J, Astrup A. Increased postprandial glycaemia, insulinemia, and lipidemia after 10 weeks' sucrose-rich diet compared to an artificially sweetened diet: a randomised controlled trial. Food Nutr Res. 2011;55. doi: 10.3402/fnr.v55i0.5961. Epub 2011 Jul 20.

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Studie 3: Tigerbalsam?

Topiske applikasjoner/kremer med Mentol/Menthol og lignende stoffer, som f. eks Tigerbalsam/Tiger balm, er effektive alternativer til andre smertestillende (paracetamol etc.), og korttids bruk ser ut til å være trygt (1-5), men er blant annet vist å redusere blodstrøm/blood flow etter tung trening (2).

- Tigerbalsam (rød) inneholder 10 % mentol/menthol, 11 % Kamfer/camphor, 6 % dementolisert mynte/mint olje, 7 % cajuput olje, 5 % Kryddernellikolje/clove bud olje, 5 % Kassiakanel/cassia olje, og en base av vaselin/petroleum jelly og parafinvoks/paraffin (6).

(notater: Haw Par Healthcare, Non-steroidal anti-inflammatory drug: NSAIDs, skader, smerte, analgetikum/analgesic, κ-opioid receptors, kappa-opioid receptors.)

* Referanser:

1) Higashi Y, Kiuchi T, Furuta K. Efficacy and safety profile of a topical methyl salicylate and menthol patch in adult patients with mild to moderate muscle strain: a randomized, double-blind, parallel-group, placebo-controlled, multicenter study. Clin Ther. 2010 Jan;32(1):34-43. Pubmed.

2) Topp R, Winchester LJ, Schilero J, Jacks D. Effect of topical menthol on ipsilateral and contralateral superficial blood flow following a bout of maximum voluntary muscle contraction. Effect of topical menthol on ipsilateral and contralateral superficial blood flow following a bout of maximum voluntary muscle contraction. Pubmed.

3) Schattner P, Randerson D. Tiger Balm as a treatment of tension headache. A clinical trial in general practice. Aust Fam Physician. 1996 Feb;25(2):216, 218, 220 passim. Pubmed.

4) Guppy L, Lowes NR, Walker MJ. Effect of a proprietary rubefacient "Tiger Balm" on rabbit skin. Food Chem Toxicol. 1982 Feb;20(1):89-93. Pubmed.

5) Galeotti N, Di Cesare Mannelli L, Mazzanti G, Bartolini A, Ghelardini C. Menthol: a natural analgesic compound. Neurosci Lett. 2002 Apr 12;322(3):145-8. Pubmed.

6) Wikipedia: Tiger Balm.

[Oddis]

Studie 3: Tigerbalsam?

Topiske applikasjoner/kremer med Mentol/Menthol og lignende stoffer, som f. eks Tigerbalsam/Tiger balm, er effektive alternativer til andre smertestillende (paracetamol etc.), og korttids bruk ser ut til å være trygt (1-5), men er blant annet vist å redusere blodstrøm/blood flow etter tung trening (2).

Dette betyr vel at tigerbalsam da kun vil virke for opplevelsen av ubehaget (symptomene), men ikke være positivt for restitusjonen? Størst mulig blodgjennomstrømming er vel ønskelig i skadet vev?

Like greit. Tiger Balsam lukter skit....

[Fredrik Gyllensten]

Dette betyr vel at tigerbalsam da kun vil virke for opplevelsen av ubehaget (symptomene), men ikke være positivt for restitusjonen? Størst mulig blodgjennomstrømming er vel ønskelig i skadet vev?

Like greit. Tiger Balsam lukter skit....

Ikke mitt felt, men generelt er det svært lite folk 'tar' for å forbedre skaden. Man tar som regel ikke paracet, Voltarol etc. for å bli frisk - man tar det for å lindre symptomene, og gir gjerne faen i de store helserisikoene som kan være involvert i overnevnte rusmidler.

[Sondre Aalbotsjord]

http://www.nejm.org/doi/full/10.1056/NEJM199607043350101#t=article

The Effects of Supraphysiologic Doses of Testosterone on Muscle Size and Strength in Normal Men

"Body weight did not change significantly in the men in either placebo group . The men given testosterone without exercise had a significant mean increase in total body weight, and those in the testosterone-plus-exercise group had an average increase of 6.1 kg in body weight — a greater increase than in the other three groups.

Fat-free mass did not change significantly in the group assigned to placebo but no exercise. The men treated with testosterone but no exercise had an increase of 3.2 kg in fat-free mass, and those in the placebo-plus-exercise group had an increase of 1.9 kg. The increase in the testosterone-plus-exercise group was substantially greater (averaging 6.1 kg). The percentage of body fat did not change significantly in any group (data not shown)."

Nå er ikke jeg noe flink til å lese studier, så jeg forsto nok ikke alt som sto. Interessant likevel.

[wingeer]

MAKSIMAL STYRKE ER EKSTREMT VIKTIG I OLYMPISK VEKTLØFTING:

En studie fra juni 2005 undersøkte relasjonen mellom maks styrke (1RM knebøy og isometrisk styrke i midt-høy pull) og ytelse i olympisk vektløfting, og fant en sterk korrelasjon; "When collectively considering scaling methods, maximum strength is strongly related to weightlifting performance independent of body mass and height differences. Furthermore, men are stronger than women even when body mass and height are obviated by scaling methods."

- Nivået: Herrer: knebøy 1RM 188.1 +/- 48.6, Clean/vending: 139.8* +/- 29.8. Kvinner: 126.7 +/- 28.3, Clean/vending: 90.3 +/- 17.6.

- Korrelasjoner: Se bilde ---->

-- Knebøy og Rykk/Snatch: 0,94.

-- Knebøy og Vending/Clean: 0,95.

-- Knebøy Sinclair og Rykk Sinclair: 0,92.

-- Knebøy Sinclair og Vending Sinclair: 0,94.

-- IPF, isometric peak force og Rykk/Snatch: 0,83.

-- IPF og Vending/Clean: 0,84.

- Diskusjon:

-- "...Considering that peak power production is ap- parently the major contributing factor for performance suc- cess among elite weightlifters (13,15) and force production is a major contributor to peak power, then maximum strength would be expected to be a major factor influencing weightlifting success. Although body mass/size obviously affect strength and weightlifting performance (Table 3), it is not well understood as to the degree of influence...."

-- "...Although generally strong, the correlations between measures of maximum strength and weightlifting performance are lower for women than men. This suggests that the women’s performance may be relatively more dependent upon other factors such as, flexibility, technique, or speed under the bar. Furthermore, data indicate that men are stron- ger than women even when accounting for body mass/size differences...." (kvinner, damer).

- DISKUSJON KONKLUSJON: "Collectively these data indicate that maximum strength is a major contributor to weightlifting success. Although technique training is invaluable during the developmental stages of training (3), continuing to pri- oritize technique training as an athlete advances toward the elite level may be counterproductive. As with other strength–power techniques, it is apparent that weightlifting technique becomes stable after a few years of training (1)–- however, other contributing characteristics such as flexibil- ity, strength–endurance, power, and maximum strength can be trained and improved for many years after technique stabilizes (2). Therefore, as a weightlifter progresses, we would argue that more training time should be devoted to strength training (and other characteristics) rather than tech- nique. This does not mean, necessarily, that technique train- ing should be abandoned. However, these data suggest that extensive technique training should be reduced, so that sufficient training time can be devoted to the further devel- opment of characteristics, including maximum strength, that are more likely to influence performance in a positive manner. (4,12)..."

(notater: Olympic weightlifting, kraft, rykk, støt, snatch, clean and jerk).

[ATTACH=full]83640[/ATTACH]

Fra hvilken nasjon er utøverene hentet ifra?

[Fredrik Gyllensten]

Fra hvilken nasjon er utøverene hentet ifra?

USA.

These studies were conducted as part of service projects in conjunction with U.S. Weightlifting and the U.S. Olympic Committee; all athletes (and parents of juniors) attending the U.S. Olympic Training Centers provided con- sent for testing as part of their participation in sport at the Olympic Training Centers.

1) Stone MH et al. Relationship of maximum strength to weightlifting performance. Med Sci Sports Exerc. 2005 Jun;37(6):1037-43. Pubmed. 2005 - Relationship of maximum strength to weightlifting performance.pdf.

[wingeer]

USA.

1) Stone MH et al. Relationship of maximum strength to weightlifting performance. Med Sci Sports Exerc. 2005 Jun;37(6):1037-43. Pubmed. 2005 - Relationship of maximum strength to weightlifting performance.pdf.

Ikke så overraskende funn, da amerikanske vektløftere typisk er langt sterkere enn resultatene i rykk og støt skulle tilsi. Tilsvarende forskning fra Russland viser høy korrelasjon mellom rykk og hurtighet under stanga.

Forferdelig design på nettsiden, men utmerket informasjon:

http://www.sportivnypress.com/documents/97.htmlhttp://www.sportivnypress.com/documents/24.html

[Fredrik Gyllensten]

Ikke så overraskende funn, da amerikanske vektløftere typisk er langt sterkere enn resultatene i rykk og støt skulle tilsi. Tilsvarende forskning fra Russland viser høy korrelasjon mellom rykk og hurtighet under stanga.

Forferdelig design på nettsiden, men utmerket informasjon:

http://www.sportivnypress.com/documents/97.htmlhttp://www.sportivnypress.com/documents/24.html

Enig, men jeg tror fortsatt det er en stor korrelasjon andre steder. Og at hastighet under stangen er viktig er ingen overraskelse, men det er ikke en 'øvelse' du kan trene for å forbedre rykket, men en egen ferdighet. Knebøy er en øvelse du kan trene utenom selve rykket.

Fra lenken din:

..."For example, a high correlation has been established between the snatch and the squat (r = 0.875), between the snatch and the static pull (r = 0.87) and between the snatch and the vertical jump (r = 0.885). There are similar correlations with the clean and jerk. The best result in the snatch should average no less than 62% of the squat; the best result in the clean and jerk should average no less than 82% of the squat.(A. V. Chernyak’s data.)... In order to improve one’s results in the snatch or the clean and jerk you need to increase results in all of the indicated exercises above the (in the words of V. Diachkov) base levels. For example, in order to snatch 150 kg an athlete needs to squat an average of 250 kg, static pull 360 kg and be able to vertical jump 89 cm. In order to achieve 150 kg in the clean and jerk you should squat with an average of 186 kg, static pull 270 kg and vertical jump 80 cm."

[Fredrik Gyllensten]

The Knees Out Discussion: Bob Takano og Brendan M. Murray on pushing the knees out during squats and pulls: En meget interessant diskusjon rundt 'knær ut' og kollaps av knærne under knebøy etc.

"...That technique from and injury standpoint creates significant stress on the knee, hips and low back. What I see is many of these athletes don’t have good control or flexibility so they compensate by altering the technique to give the perception they are going deeper."

- Brendan M. Murray.

"I had a thought to why people might be doing this. Some people experience valgus collapse due to week abductors and overall leg strength. When this happens I’ve heard people, mostly in big commercial gyms, say push your knees out to compensate for valgus collapse. Not realizing that perhaps what they should do is lighten the load or modify it and work on proper technique and build overall leg strength. It could be that some people continue this, pushing the knees out, because it is now a natural habit for them and have not been educated on proper squatting technique. Just my thought. Thanks."

- Tim Gabriel CSCS.

"Knees out is an expression for creating stability (and safety) at the level of the hips and ankles. From an anatomical standpoint, it also un-impinges the hips allowing the femur to continue flexing without running into the pelvic bowl."

- Diane Fu / Co-Worker with Kelly Starrett.

"...Second is the idea that a valgus knee (aka knock-kneed or knees buckling in) will increase stress on the MCL and ACL. This is true in an extended knee (the greatest strain on the ACL is between ~30 degrees flexion to ~10 degrees hyperextension). However, the knee is more stable, and the ACL and MCL on slack with increased knee flexion (particularly at angles greater than 60 degrees). In a deep squat, the knees may “buckle in” without the knee joint actually going into valgus. In fact, a recent paper found that training to prevent the knees from “buckling in” does not change the actual valgus in the knee joint... A varus knee (aka bowed knees) has potential complications as does a valgus knee. Therefore, taking a knee in valgus to a varus position is just as dangerous. The varus knee will increase strain on the LCL, a wider stance will increase strain on the PCL, and extreme abduction + external rotation of the thigh is associated with hip labral tears."

"Incidentally, there is recent research that finds that a lack of leg dorsiflexion contributes to knee valgus. This is interesting on two fronts. First, most attempts to move the knee from valgus to varus are done by activating the hip external rotators and abductors. If the problem arises from the ankle, the use of these hip muscles is non-sensical as it activates muscles for a purpose they should not be used for. Second, it highlights the importance in achieving good leg dorsiflexion to perform a squat. From my research, I would say the leg should, at minimum, be rotated forward from the vertical 30 degrees to perform a squat. In proficient squatters, the angle is between 35-45 degrees. One of my grad students has a paper in press in the Journal of Strength and Conditioning Research that finds these angles occur when performing a clean, power clean and landing from a jump. There is plenty of research that associates a range of injuries with poor dorsiflexion, so it is critical that this range of motion is developed in athletes." (Ankelmobilitet, ankel flexibility, ankelfleksibilitet, ankel mobility, ankel dorsifleksjon.)

"I would also like to emphasize the importance of neutral elsewhere in the body when performing exercises. I see as much fervour in people overarching their back as in pushing their knees outward while lifting weights. While a flexed spine, particularly under load, is dangerous, a hyperextended spine is just as dangerous. Neutral is neutral, and a deviation from neutral, whether spine flexion or spine hyperextension increases the risk of injury, and reduces the mechanical efficiency. Lumbar spine hyperextension can lead to facet joint injuries, pars fractures, and nerve compression in the intervertebral foramen.."

"Although I didn’t understand it back then, the large extensor efforts from the erector spinae have to be balanced by flexor efforts from the abdominals to prevent the spine from hyperextending. Although sit-ups and crunches have fallen out of vogue in the S&C and fitness communities, they are exercises my athletes do regularly and this has contributed to keeping them healthy. Most of my athletes are volleyball players and this is a population where back problems from spine hyperextension are very common." (Crunches, sit-ups, magetrening.)

- Loren Chiu, PhD, CSCS.

"...In what I know of the knees out technique the goal is to increase external of the femur and hip. This would restrict motion at the hip during the movement....I would completely understand this technique change for power lifting since the range of motion in the hip, low back and knee is less then required for Olympic movements. My question is cross fit uses Oly lifts in the work outs so limiting mobility in the hip is not advantageous to these lifts. If you increase external rotation and abduction of the hip to increase stability you affect/limit mobility. Limited mobility in the hip requires increase movement and stress on the joints above and below the hip...When I have evaluated these athletes clinically the one consistent finding I have seen is restricted hip motion in internal rotation compared to external rotation. These findings match what has been reported in the literature."

- Brendan M. Murray D.C., D.A.C.B.S.P.

"...Many many many CrossFitters have mentioned that they are instructed to push the hips back and the knees out while performing a squat. This I feel promotes two things – 1.) a significant forward lean and 2.) an over exaggeration of the lumbar curve. The forward lean will put the lifter into more of a good morning position than a truly optimal back squat position which is that with more of a vertical torso. This also limits the motion from the two other joints required for a good back squat: the knee and the ankle. I believe the general view of someone “squatting on their toes” is over corrected by cueing the hips to go back instead of correcting what is possibly more of a lower leg mobility issue which would limit the lifters ability to remain flat footed with an upright torso during a squat. The same said lifter could also be creating an over exaggerated lumbar arch in attempt to get back on the heels, which essentially puts the lifter at the risk of just “hanging out” on that lumber spine in excessive extension past neutral.... However, I think it could all boil down to a lack of education on proper technique/biomechanics. Many of the new coaches especially in the CrossFit realm come from backgrounds unrelated to exercise or sport performance so when presented with a “coach knees out, hips back” as the proper way to instruct squatting it is applied across the board regardless of an individual lifter’s ability."

- Angie Sorensen.

...

"...From a performance standpoint, I’ve seen this promoted by geared powerlifters to maximize the stretch reflex in the squat. I believe the most influential advocates of the knees out style was Westside Barbell although I’m not certain. Regardless, it’s something I think came from powerlifting’s low bar style squats and spilled over into other domains of strength training."

- Niel Patel

CONCLUSION: "...the practice of turning the knees out in the squat and pull...Now this hypothetical model may be entirely correct with regards to generating torque but to to verify this, the model must be subjected to scientific testing. I have not seen such supportive evidence. And although it may be an accurate, testable hypothesis supported by scientific evidence at some point, it may not be providing what is necessary for some athletes to be more successful in their lifting and hence should not become a universal recommendation for all coaches working with all athletes...."

"...There are literally thousands of university trained, professional weightlifting coaches that have been coaching these athletes for the past several decades. They are employed by the ministries of sport in a wide variety of nations and are granted significant financial rewards and societal esteem for coaching athletes to the medal podium. If the simple act of turning the knees further out would have provided their lifters with an advantage in competition, it certainly would have been put into play by this time....So in conclusion, you are free to believe or support whatever beliefs you’d like. The initiator of this discussion, Dr. Murray, has provided some input that I think needs to be considered by coaches who are in the trenches working with athletes. He has found that the universal application of the “knees out” cue has led to a higher than normal number of knee and lower back injuries and that eliminating that cue has enabled his patients to train without pain in previously affected joints. All professional and most non-professional weightlifting coaches are not employing the “knees out” strategy, and no top lifters are finding it to be especially productive. The decision on this issue is yours."

- Bob Takano

* Referanser: Takanoathletics.com: Del 1, Del 2, Del 3, Del 4, Del 5, Del 6/Finale.

[wingeer]

Har nå lest alle 6 innleggene, men føler at de alle snakker forbi hverandre? Hva menes egentlig med "knær ut" og hvordan definerer de "to sidene" dette?

[Alexander V]

Har nå lest alle 6 innleggene, men føler at de alle snakker forbi hverandre? Hva menes egentlig med "knær ut" og hvordan definerer de "to sidene" dette?

Enig. Virker ikke som om partene egentlig er enig om hva som diskuteres. Leste gjennom alle innleggene, og synes det blir litt håpløst å fremstille det som det blir gjort. Tror at i en live debatt mellom Kelly Starrett/SFCF-folk og WL-coachene, ville de funnet ut at de egentlig er veldig enige.

All professional and most non-professional weightlifting coaches are not employing the “knees out” strategy, and no top lifters are finding it to be especially productive.

Dette er jo absurd, og tyder på at forfatteren ikke er kjent med Starretts ideer om hip-torque. Det er jo ingen tvil om at mange toppløftere bruker teknikker som passer veldig godt inn i det Starrett mener er ideelt. Han har jo bl.a. nevnt en del kinesiske løftere som nær "fasiten" når det kommer til posisjonering.

Knees out?

[wingeer]

Se også dyppen til overstøtet på tilnærmet alle vektløftere på elitenivå.