Let's talk more about these "antagonistic pairs". A great example pair is your biceps brachii and triceps brachii. Before we go any further, we need to first review a few anatomical terms of motion. Contracting your biceps exhibits flexion, i.
So, your biceps is described as a "flexor" muscle. In the illustration below, the image on the right shows the biceps flexing. The opposing muscle of a flexor is called the "extensor" muscle. Your triceps is an extensor. When you contract your triceps your arm straightens and the angle between the forearm and the upper arm increases. You may have already guessed but this is called "extension" and you can see that in the left illustration below.
These designations are intrinsic, meaning they are an unchangeable property of the muscle. This means that contracting a flexor muscle will always exhibits flexion and never extension and vis versa for contracting extensor muscles. Okay, so now that we have our terms of motion established we can discuss these antagonistic pairs properly! The two muscles in an antagonistic pair are in opposition. That is, if one extends a limb during its contraction, the other will return the limb to its original position when flexed.
In each pair, depending on the movement, one muscle plays the role of the "agonist" and the other muscle plays the role of "antagonist".
The agonist is a muscle that contracts to cause the movement. The antagonist is an opposing muscle that relaxes relatively to stretch. These two roles, agonist and antagonist, can be exchanged back and forth. To visualize this, let's jump back to our biceps and triceps example.
Image waving at your best friend: when your hand is moving away from you, your triceps is an agonist, contracting to extend your arm. Your biceps is an antagonist, relaxing to allow elongation while possibly contracting ever-so-lightly to control the speed of that moving forearm. When your hand is moving back in during your waving motion your biceps is an agonist, flexing your arm towards you.
In this case, your triceps is an antagonist and must relax to stretch to allow the movement. So you can see that unlike the intrinsic designations of the flexors and extensors, the two roles of antagonistic pairs are dependent on the motion. If the motion is reversed, the agonist and the antagonist switch roles.
It's not always this simple though! In some movements, such as a push-up, the agonist doesn't change with the direction of motion. The damaged ends of the tendon are brought together with sutures to achieve a secure repair. If the tendon injury is severe, a graft may be required. A graft is a piece of tendon that is derived from other parts of the body such as a foot or toe. After the repositioning of the tendon, the incisions are closed with sutures and a dressing pad is placed over the surgical site.
Your surgeon will place your hand in a protective splint to restrict movements. Depending on the injury, you will be advised to start hand therapy for a few weeks following surgery.
This is to improve the movement of the finger. Possible complications of surgery include pain, bleeding, infection, stiffness, rupture of the repair, and damage to the surrounding nerves or blood vessels. A second surgery may be needed to release any excess scar tissue that interferes with finger movement. Flexor tendon injuries are common and usually result from a laceration type injury. These injuries are clinically problematic because they cannot heal without surgical treatment, which involves bringing the two ends of the broken tendon back together for healing to occur.
Flexor and Extensor Tendon Injuries. Causes Any cut or laceration to the arm, hand, or fingers can cause a flexor tendon injury.
Treatment A ruptured tendon cannot heal without surgery because the cut ends usually pull away after an injury. No significant differences between groups were found for peak torque, average torque, total and average work ratio of the elbow flexors and extensors at either speed. In addition, the muscle strength ratio did not differ significantly between the dominant hand and non-dominate hands in either group. The main findings of this study were that the elbow extensors produced greater torque and work than the elbow flexors.
Results showed peak torque ratio of 0. This is in agreement with previous studies: Maquet et al. Similar ratio findings were reported in studies of judo 0. Complimentary evidence regarding the strength of the elbow extensor vs. The physiological cross sectional area PCSA of the elbow muscles which defined as the muscle volume divided by the length of the muscle fibers measured in cadavers, showed that triceps brachii has the largest PCSA of the elbow muscles and can produce the greatest muscle force of all elbow muscles [ 3 , 25 ].
Another study used magnetic resonance imaging MRI and demonstrated that the triceps brachii has greater torque potential than any other elbow muscle and its PCSA is 1. A study in climbers, looking at shoulder flexor and extensor muscle strength, established the greater strength of the shoulder extensors over the flexors [ 27 ].
The triceps brachii is a synergist to shoulder extension movement, but it is also a strong elbow extensor. Therefore, it is possible that this dual role contributed to the fact the elbow extensors in climbers were stronger than the flexors. The results of these studies are in agreement with our findings, indicating that elbow extensors are stronger than elbow flexors.
This is consistent across other sports that involve the upper limbs. In addition, climbing can be regarded as a symmetrical, bilateral sport that requires participation of all 4 limbs. Accordingly, we hypothesized that climbers would exhibit symmetrical strength, which was indeed found. These findings are in agreement with previous findings in swimmers [ 17 ], and even in tennis players [ 21 ], suggesting that elbow flexor-extensor muscle strength is symmetric and is not influenced by lateral dominance in trained athletes.
In contrast to the study hypotheses, the results did not demonstrate significant differences in torque and work between climbers and nonclimbers. The fact that no differences were found between climbers and nonclimbers is consistent with previous studies that showed no differences in grip strength between recreational climbers and non-climbers [ 28 , 29 ]. However, since our climbers trained in average This can be explained by our assessment tool consisted of isokinetic dynamometer testing performed in an open kinetic chain, that is not functional testing for climbing.
Climbing involves a closed kinetic chain pattern. It may be that the isokinetic testing used in this study could not evaluate the relevant, unique muscle strength achieved by climbers. Further research is needed in a larger sample, including additional functional measures relevant to climbing, such as pull-ups, grip strength, and climbing grades.
To the best of our knowledge, this is the first study to investigate elbow muscle torque and work in climbers. Therefore, additional studies are needed to characterize strength ratios around the joints of the upper limb in climbers. This study did not support the assumption that climbers would have increased elbow strength as compared with non-climbers, but additional larger studies are needed to confirm this finding and to expand the investigation of this special population.
J Nov Physiother 9: DOI: This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Select your language of interest to view the total content in your interested language. Home Publications Conferences Register Contact. Journal of Novel Physiotherapies Open Access. Guidelines Upcoming Special Issues. Participants The climbers were recruited from climbing clubs in the city of Haifa, Israel.
Br J Sports Med Sports Med Maitland M Injuries associated with rock climbing. J Orthop Sports Phys Ther Scand J Med Sci Sports Bollen SR Soft tissue injury in extreme rock climbers. Int J Sports Med
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