| ΠΡΟΕΠΙΣΚΟΠΗΣΗnbsp; ΘΕΜΑΤΟΣ |
| gtsig |
Δημοσιευτηκε - 24/10/2016 : 08:28:16
Έχει κάνει κανείς κρυοσάουνα/κρυοθεραπεία; Παλεύεται η θερμοκρασία; 
Επίσης, επειδή έχω κερδίσει μία συνεδρία, προτείνετε να την κάνω πριν ή μετά το μαραθώνιο; |
| 15 ΤΕΛΕΥΤΑΙΕΣ ΑΠΑΝΤΗΣΕΙΣ (Πρώτα η πιο πρόσφατη) |
| spiros tsi |
Posted - 27/11/2016 : 01:19:08
Ενα αλλο αρθρο -ανασκοπηση ερευνων απο την ιδια πηγη σχετικα με τις στατικες διατασεις πριν και μετα τις αθλητικες δραστηριοτητες .
Questioning the Use of Static Stretching Before and After Athletic Activities
Written by: Dr. Bahram Jam, PT
Advanced Physical Therapy Education Institute (APTEI), Thornhill, ON, Canada January 31, 2015;
Static stretching (SS) is performed by athletes and non-athletes, and is often strongly encouraged by personal trainers and coaches. SS is also frequently prescribed by health care providers such as physical therapists following various musculoskeletal injuries. The standard justifications given for doing SS on a regular basis is that it i) helps improve muscular and tendon flexibility ii) improves athletic performance iii) reduces post exercises soreness and most importantly, SS allegedly iv) reduces the risk of future injuries.
The purpose of this bound-to-be controversial paper is to demonstrate how the cumulative evidence to date in fact disproves all the above-mentioned hypothesized benefits of SS. To help clinicians make the transition away from SS focused interventions, this paper will also provide alternative evidence-based options to SS.
Assumption #1: The current evidence supports that SS lengthens muscles and tendons. ¤ True False
There is certainly evidence that SS improves flexibility and range of motion (ROM), but very often the changes appear to be shortlasting (i.e. 30 minutes) (de Weijer et al 2003, Ford et al 2007). A systematic literature review on hamstring stretching concludes that several weeks of SS does result in improvements in hamstring flexibility and increases in ROM (Decoster et al 2005). The automatic assumption may be that the improvements in
ROM are obviously a result of increased length of the muscle fibers and tendons. Questioning the theory that muscle fibers actually lengthen with SS, a study not only measured changes in ROM, but actually analyzed the effects of a 6 week SS program on gastrocnemius muscle and Achilles tendon fiber length (Konrad et al 2014). Although significant improvements in ROM were made following SS, fascicle length and tendon junction displacements as measured with ultrasound were unaltered. The authors hypothesize that the improvements in ROM could not therefore be explained by actual structural changes in the muscle and tendon units but the increase in flexibility may be due to adaptations of nociceptive nerve endings allowing for increased stretch tolerance.
Perhaps dancers, gymnasts and Yoga practitioners who stretch regularly, can gradually stretch further because either they have less pain while they stretch or they simply can tolerate more pain. A number of studies have proposed that the increased ROM following SS may be due to alterations in stretch sensation and tolerance, rather than alterations in actual muscle extensibility (Weppler & Magnusson 2010).
A clear example that muscle length is not necessarily the limiting factor to ROM is that
PTs, say “NO” to SS
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compared to being awake, a person under anesthetic can be stretched much further; obviously anesthesia has no effect on muscle or tendon fiber length. Similar to anaesthesia, at least in the short term, SS may have little effect on muscle, tendon and fascicle length.
Other options for lengthening muscles and tendons
Studies have demonstrated that eccentric strength training produces changes to the mechanical properties of the muscles and tendons resulting in increased fascicle length and improved flexibility (Mahieu et al 2008, Duclay et al 2009).
Clinical Conclusion #1: Based on the available evidence we can safely conclude that SS does improve joint and muscle flexibility, however the flexibility gained may not always be from actual tissue fiber lengthening. If muscle fiber lengthening is required, eccentric strengthening exercises to end of range may be more effective.
Assumption #2: The current evidence supports that SS improves athletic performance. ¤ True False
To date, SS has never been shown to actually improve athletic performance, yet it is almost preached by many as factual. Ironically studies have shown SS to have a slightly detrimental effect on performance. A study on elite college sprinters showed that pre-run SS significantly increased their 40 meter sprint time, meaning it actually inhibited sprint performance (Winchester et al 2008).
A systematic review based on 106 papers concluded that SS of 30-45 seconds has no positive or detrimental effects on muscle performance but SS of longer duration (>60 seconds) may have detrimental effects on eccentric muscle strength (Kay et al 2012). A meta-analysis based on 104 studies evaluating the effects of SS on muscular performance states, “We conclude that the usage of SS as the sole activity during warm-up routine should generally be avoided.” (Simic et al 2013).
Instead of discussing every one of the 104 studies mentioned above, here is a sample one where 30 recreational gym goers were given a standardized 10-week strength training protocol, then were randomly assigned to one of three groups. The first group was provided with no SS exercises, the second group was instructed on performing SS pre-workout and the third group was instructed on performing SS in between every training set. Here is the word by word conclusion of this study published in the Journal of Strength and Conditioning Research, “... strength training performed without any type of stretching exercise, regardless of whether the stretching is performed before or during the lifting session, can more effectively increase muscle strength” (Borges Bastos et al 2013).
To evaluate the potential effects of stretching on vertical jumping height, 100 athletes
Warmed-up pre-sprint
Stretched pre-sprint
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performed vertical jumps 2 minutes after various stretching protocols. They demonstrated that athletes who performed either static or proprioceptive neuromuscular facilitation (PNF) stretches had decreased vertical jump performance but on the other hand those who performed ballistic stretching had increased vertical jump performance (Place et al 2013).
In the past decade studies have either shown that SS has a negative influence or at best no influence on endurance performance of activities such as walking, running or cycling (Mojock et al 2011, Hayes et al 2007, Allison et al 2008). To quote another paper published in the Journal of Strength and Conditioning Research, “...static stretching should be avoided before a short endurance bout.” (Lowery et al 2014).
Other options for improving athletic performance
There are certainly hundreds of published studies on means of improving athletic performance such a adequate hydration (Maughan 2010), proper nutrition (Zoroob et al 2013), neuromuscular warm up (Herman et al 2012), strength training (McGuigan et al 2012), and psychological preparation (Luiselli 2010). The point is: there are several other more effective ways of potentially improving athletic performance and SS is not one of them!
Clinical Conclusion #2: Based on the available evidence, we can conclude that SS does not appear to improve muscular contractions and in some cases actually hinders them. Warm-ups and strength and endurance training involving functional movements simulating the athletic performance continue to be the best methods of improving athletic performance.
Assumption #3: The current evidence supports that SS reduces post-exercise muscle soreness. ¤ True False
The 2011 Cochrane review based on 12 studies published over the last 25 years concluded that SS does not prevent muscle soreness that occurs 8 to 24 hours after vigorous exercise.
“The evidence from randomised studies suggests that muscle stretching, whether conducted before, after, or before and after exercise, does not produce clinically important reductions in delayed-onset muscle soreness in healthy adults.” (Herbert et al 2011).
Other options for reducing post-exercise muscle soreness
A warm-up performed immediately before an unaccustomed eccentric exercise has been shown to have small reductions in delayedonset muscle soreness (Law & Herbert 2007, Ingham et al 2010). However the single most effective method of minimizing this soreness is the common sense approach of starting a novel exercise or activity gradually and progressing the intensity over a period of 1 or 2 weeks (Cheung et al 2003).
Clinical Conclusion #3: Based on the available evidence we can conclude that SS neither prevents nor reduces post exercise muscle soreness, whereas a warm-up and gradual exercise intensity progression appear to be the best methods of preventing this adverse effect.
Assumption #4: The current evidence supports that SS reduces the risk of injuries. ¤ True False
To reduce the risk of musculoskeletal injuries, it is common for professional and recreational athletes to perform various stretching routines
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prior to their athletic activities. Considering the extreme popularity of this hypothesis, one would believe in the existence of overwhelming evidence supporting the notion that SS reduces the risk of future injuries. The challenge in proving or disproving this hypothesis is that the risk factors for various musculoskeletal injuries are multi-factorial and complex.
Admittedly there are a few studies that do support tightness and restrictions in ROM to be risk factors in injury recurrences (Jonhagen et al 1994, Witvrouw et al 2001), however these studies still do not necessarily support SS for injury prevention. For example increased hamstring or quadriceps muscle tightness in soccer players has been shown to be a risk for subsequent musculoskeletal injuries (Witvrouw et al 2003), yet this finding does not automatically indicate that if the athletes had stretched their hamstring or quadriceps, they would have prevented their injuries.
A study on Australian footballers showed that the toe-touch test, measuring lumbar flexion and hamstring flexibility, was not a useful screening tool to identify footballers at risk for hamstring strain (Bennle et al 1999).
Another study on 30 elite Norwegian soccer teams demonstrated no difference in the incidence of hamstring strains between the teams that used a flexibility training program and those who did not (Arnason et al 2008).
This is one of largest studies on SS involving over 1500 new army recruits who were randomly allocated to either a daily warm-up and stretching exercises or only warm up exercises for 3 months. The stretching
exercises included 20 seconds of SS involving the six major lower extremity muscles (gluteals, hip flexors, quadriceps, hamstrings, adductors, and ankle plantar flexors) before their daily physical training sessions. During the 3 months of training, 333 lower limb injuries ranging from muscle strains to stress fractures were recorded, however there was no effect of pre-exercise stretching on injury risk. Interestingly the two factors that predicted injury risk, were pre-existing fitness test (20m shuttle run score) and age (Pope et al 2000).
Here is a quote from a paper published in the British Medical Journal “... muscle stretching before exercising does not produce meaningful reductions in the risk of injury.” (Herbert et al 2002) and another one published in the Medicine and Science in Sports and Exercise journal, “Stretching was not significantly associated with a reduction in total injuries” (Thacker et al 2004).
Thus far, 3 systematic reviews have all reached the same conclusion: SS exercises are proven to be not beneficial for sports injury prevention (Thacker et al 2004, Hart 2005, Lauersen et al 2014).
Other options for reducing the risk of future injuries
Based on the previously mentioned study on Norwegian soccer teams, although SS failed to work, they demonstrated significantly lower incidences of hamstring strains in teams who used an eccentric training program when compared to the teams that did not use the program. Thus, eccentric strengthening was an effective method of reducing the risk of hamstring injuries (Arnason et al 2007).
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Similarly, a study on Swedish soccer players who had sustained hamstring injuries demonstrated those who performed eccentrically focused exercises had almost half the recovery time when compared to those who received stretching and conventional exercises (Askling et al 2013).
There is now strong evidence that gradual progressive strength training performed consistently can greatly reduce the risk of occurrence and recurrence of various musculoskeletal injuries (Lauersen et al 2014). A paper published in the British Journal of Sports Medicine concluded that “Strength training reduced sports injuries to less than 1/3 and overuse injuries could be almost halved.” (Lauersen et al 2014).
Clinical Conclusion #4: Based on the available evidence, we can safely conclude that SS is not effective at reducing the risk of musculoskeletal injuries. On the other hand appropriate neuromuscular warm-up and eccentric strength training exercises appear to dramatically reduce the risk of injury and improve recovery following muscle and tendon injuries.
Grand Conclusion: Despite the growing worldwide popularity of SS over the past number of decades, personal trainers, coaches and health care providers must consider the overwhelming evidence that SS may not be an effective means of i) improving muscular and tendon flexibility ii) improving athletic performance iii) reducing post exercises soreness and most importantly, SS is not effective in iv) reducing the risk of future musculoskeletal injuries.
In contrast to SS, dynamic stretching and eccentric strengthening may stimulate mechanoreceptors, augment proprioception, and potentially reduce injury risk and improve athletic performance. Future studies should focus on the effects of dynamic stretching and neuromuscular warm-ups simulating the functional movement pattern of the particular activity or sport. Perhaps the time has come to put our obsession with static stretching to rest!
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| spiros tsi |
Posted - 27/11/2016 : 00:58:41
Εκ των προτερων να ζητησω την επιεικεια σας για τα παρακατω 2 αποσπασματα που ειναι στα Αγγλικα.Θα μου ηταν λιγο κουραστικο να τα μεταφρασω.Ελπιζω και λογω ηλικιας να ξερετε οι περισσοτεροι Αγγλικα.Σας μεταφερω το αποσπασμα ενος αρθρου του Dr. Bahram Jam, DScPT, MPhty, BScPT, CredMDT του Advanced Physical Therapy Education Institute (APTEI)στον Καναδα.
In this experimental study (Takagi et al 2011), the muscle belly of the extensor digitorum longus of anaesthetized rats was crushed for 30 seconds using forceps, to which a weight (500g) was attached. Immediately after the injury the rats were randomly divided into two groups, the no icing group and icing group where they lightly placed fine crushed ice in a tiny polyethylene bag on their injured hind leg for 20 minutes.
At 12 h and 1, 2, 3, 4, 5, 6, 7, 14 and 28 days after the injury, their injured muscles were microscopically and physiologically analyzed. I have summarized and have very much simplified the results of this study in the following chart.
Influence of Icing on Muscle Regeneration After Crush Injury to Skeletal Muscles in Rats
TIME AFTER INJURY NO ICING GROUP ICING GROUP
12 hours Macrophages were found within the necrotic muscle fibers (Macrophage migration to an injured site to phagocytose the necrotic muscle fibers is essential for “clean-up”) Less macrophages were found within the necrotic muscle fibers
Day 3 Regenerating muscle cells present Reduced regenerating muscle cells
Day 4 Normal sized muscle cells produced Smaller sized regenerating muscle cells
Day 14 Normal maturation of the regenerating muscle fibers Maturation of the regenerating was visibly reduced
Day 28 Cross-sectional area of the regenerating muscle was 65% greater than the icing groupCollagen fibers were seen only among the bundles of muscle fibers as it is seen in healthy muscles Regenerating muscle fibers was significantly less in the icing group (P < 0.01)Abnormal collagen formation where collagen fibers surrounded each muscle fiber
Takagi, R, et al. Influence of Icing on Muscle Regeneration After Crush Injury to Skeletal Muscles in Rats. J of App Phys. February 1, 2011 vol. 110 no. 2 382-388
http://jap.physiology.org/content/110/2/382
The final summary sentence from the above-mentioned study published in The Journal of Applied Physiology is,
No Cold Packs“Judging from these findings, it might be better to avoid icing, although it has been widely used in sports medicine.”
As health care providers we must ask ourselves if the temporary (20-30 minutes) pain reduction and numbness is worth the potential hindrance to the proper maturation and collagen formation.
You may be asking yourself; surely this is just one study, what about all the other studies supporting the use of ice? I will reply with,“what other studies?”
The Cochrane review on low back pain (French et al 2006) concludes that to date there is some evidence supporting the use of heatevidence on the use of cryotherapy.
An analysis of 11 trials involving 868 patients (van den Bekerom et al 2012) concludes that there is insufficient evidence from randomized controlled trials to determine the relative effectiveness of RICE therapy for acute ankle sprains.
The most recent systematic review (Bleakley et al 2012) based on 35 clinical trials suggests that athletes may in fact be at a performance disadvantage if they return to their athletic activity immediately after 20 minutes of icing.
Another systematic review (Bleakley et al 2004) based on 22 clinical trials concluded that the effect of cryotherapy on acute injuries such as muscle strains and contusions has not yet been shown. Here is a direct quote from the paper, “There was little evidence to suggest that the addition of ice to compression had any significant effect”.
Icing of sore muscles after a hard athletic workout is commonly thought to help recoveryand promote earlier return to activity. This experimental study in fact demonstrated the opposite to occur (Tseng et al 2013). After performing 6 sets of heavy eccentric triceps workout, half the athletes were randomly allocated to receive either 15 minutes of cooling ice pack or a sham pack. After 2 and 3 days the icing group had significantly greater creatine kinase and myoglobin (signs of muscle overload) and the athletes subjectively reported of having more triceps fatigue than the sham ice group.
Here is a quote from the above-mentioned paper published in the Journal of Strength & Conditioning Research,
“These data suggest that topical cooling, a commonly used clinical intervention, seems to not improve but rather delay recovery from eccentric exercise-induced muscle damage”.
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| Droulas13 |
Posted - 22/11/2016 : 15:40:22
Επίσης αν η ευλυγισία φεύγει, τους γιόγκερς πως τους εξηγείς; |
| Rigelian |
Posted - 22/11/2016 : 14:38:57
Σε κάθε τραυματισμό εκκρίνονται ενδορφίνες; |
| v_run |
Posted - 22/11/2016 : 14:26:45
spirostsi: Αυτό που λες ότι:
"Το αργοτερο σε μια μερα η ευλυγισια εχει φυγει"
το εννοείς;
γιατί η πραγματικότητα είναι διαφορετική..
Με διατάσεις το πόδι, ο μυς, ο τένοντας δεν ξέρω τι ακριβώς, υποθέτω όλα, είναι πιο ευλύγιστα
Χωρίς διατάσεις είναι λιγότερο ευλύγιστα.. |
| Droulas13 |
Posted - 22/11/2016 : 14:15:12
Ο πάγος και υποθέτω το κρύο νερό κακοποιεί το σώμα και αυτό παράγει ενδορφίνες και αυτές μας κάνουν προσωρινά χαρούμενους, ε;
Τότε λοιπόν πως εξηγείται το φαινόμενο (προσωπικά και σε πολλούς συναθλητές που ξέρω) μετά από long run να βρέχουν για τα πόδια τους με παγωμένο νερό και την επόμενη μέρα να τα νιώθουν, όπως ακριβώς θα τα ένιωθαν μετά από 2-3 μέρες αν δεν είχαν ρίξει κρύο νερό; |
| spiros tsi |
Posted - 22/11/2016 : 13:53:12
Τις στατικες διατασεις τις θελετε γιατι παιρνετε ευλυγισια και νιωθετε πιο ωραια μετα απο καθε φορα που τις κανετε.Ετσι δεν ειναι?Κοιτα τι παιζει τωρα.Την ευλυγισια δεν την παιρνετε απο τον μυ αλλα απο τους τενοντες.Αυτοι ειναι που τεντωνουν.Ο μυς προσπαθει να αντισταθει,ενεργοποιωντας το αντανακλαστικο διατασης και στην πραγματικοτητα κονταινει.Γι αυτο και καθε φορα που κανετε διαταση οι αντιθετες αυτες δυναμεις προκαλουν μικροτραυματισμους.Αυτοι προκαλουν την εκκριση ενδορφινων οπως καθε φορα που τραυματιζομαστε.Γι αυτο νιωθετε πιο ωραια.Το αργοτερο σε μια μερα η ευλυγισια εχει φυγει,οι ενδορφινες εχουν υποχωρησει, αλλα ο μυς αν δε δουλευτει μενει λιγο πιο κοντος.Και ο αθλητης νιωθει παλι την αναγκη να κανει διατασεις κοκ. |
| Deorum |
Posted - 22/11/2016 : 12:20:10
Εντάξει, έχεις την άποψή σου, αλλά μην επικαλείσαι αυτό που δεν αναμεταδόθηκε από το runningnews.gr ή τον αρχικό συγγραφέα γιατί είναι διαφορετικό. |
| spiros tsi |
Posted - 22/11/2016 : 12:03:24
Kαι για μετα το ιδιο ισχυει για αλλους λογους.Καποια στιγμη θα το καταλαβουμε και αυτο |
| Deorum |
Posted - 22/11/2016 : 11:25:53
Προφανως σου διεφυγε μια σημαντικη παραμετρος. Το "πριν το τρεξιμο". Οχι γενικα και καθολικα |
| spiros tsi |
Posted - 22/11/2016 : 10:17:28
Ριξτε μια ματια σημερα στο αρθρο του Kelly o Mara στο running news για να δειτε τη ζημια που κανουν οι στατικες διατασεις.Τα ιδια Θα βρειτε αλλου για τον παγο.Εγω το χρεος μου να μεταφερω τις γνωσεις αυτες και να βοηθησω οποιον θελει να βοηθηθει το εκανα.Ηδη πολλοι εχουν αναθεωρησει η τουλαχιστον προβληματιστει για το τι πραγματικα παιζει. |
| Rigelian |
Posted - 22/11/2016 : 09:46:08
quote:
Originally posted by spiros tsi
Αμφισβητεις και την 5000 χρονων ιατρικη των Κινεζων τωρα?Την πατησανε οι κινεζοι.
Ναι. Αμφισβητώ ο,τιδήποτε δεν μου δίνει σαφή σχέση αιτίου και αποτελέσματος. Δέχομαι την ιατρική, τους φυσιοθεραπευτές, τους φαρμακοποιούς, ο κάθε ένας στον ρόλο του, επιστήμονες, καταρτισμένους και εκεί πάω αν χρειαστώ κατι, αχρείαστοι νά'ναι!
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| spiros tsi |
Posted - 22/11/2016 : 09:35:57
Αμφισβητεις και την 5000 χρονων ιατρικη των Κινεζων τωρα?Την πατησανε οι κινεζοι. |
| Bloom |
Posted - 22/11/2016 : 09:33:20
quote:
Originally posted by spiros tsi
Πριν 15 χρονια εκανα μαθηματα κινεζικης ιατρικης στο πανεπιστημιο της τσεγκντου στην κινα.Οι κινεζοι ηταν σφοδρα εναντιον του παγου.
Όταν λοιπόν έγραφα για το τσάτρα και το πάτρα, το γινγκ και το γιανγκ δεν είχα καθόλου άδικο...
Και είναι απολύτως λογικό ο πάγος να είναι άχρηστος αν είναι τη θεραπεία να την αναλάβουν ο Γκάλνταφ και ο Σάρουμαν... |
| spiros tsi |
Posted - 22/11/2016 : 09:33:17
quote:
Originally posted by spiros tsi
Πριν 15 χρονια εκανα μαθηματα κινεζικης ιατρικης στο πανεπιστημιο της τσεγκντου στην κινα.Οι κινεζοι ηταν σφοδρα εναντιον του παγου.Εγω δεν μπορουσα να το δεχτω με τιποτα Ρωτησα ενα γερο μεγαλο δασκαλο:ουτε στα διαστρεμματα να μη βαζω?και μου απαντησε οτι ο παγος ειναι μονο για τους νεκρους.Περασαν πανω απο 10 χρονια για να συνειδητοποιησω οτι ειχε δικιο.
Προσφατα διαβασα μια ερευνα που ελεγε οτι το 30% οσων βαζουν παγο σε διαστρεμμα ενα χρονο μετα υποφερουν ακομη.
Δεν ειναι ευκολο να αλλαξουμε πραγματα που εχουμε δεδομενα για χρονια αλλα εκει βρισκεται και η ευφυια του καθενος.Το οτι εμενα μου πηρε 10 χρονια ελπιζω να μην με κατατασει στους βλακες.
Fanis δεν το πηρα αλλιως.Σε ευχαριστω για τα καλα σου λογια
Nrun εισαι πολυ σωστος.
Deorum δεν ειναι ετσι.Η βασικη αιτια που δεν ξεπρηζονται τα διαστρεμματα ειναι ο παγος. Παροτι αρχικα μειωνει το πρηξιμο μετα δεν το αφηνει να αποροφηθει.
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