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Simple Summary: This study compared the muscle fiber composition of working and companion dog breeds to understand how their muscles adapt to breed-specific tasks. By analyzing the triceps brachii and biceps femoris muscles of 12 dogs, we found that working dogs had larger muscle fibers, a higher proportion of endurance-related fibers (types IIa and I), and more nuclei per fiber, which support strength and endurance. Companion dogs, on the other hand, had more fibers suited for short bursts of activity (type IIb) and fewer nuclei per fiber, suggesting slower muscle regeneration. These results highlight the role of selective breeding in shaping muscle structure and function in dogs. The structural and functional characteristics of skeletal muscle fibers play a crucial role in understanding the physical capabilities of dogs, particularly in relation to their breed-specific roles. This study aimed to compare the muscle fiber composition of working and companion dog breeds by analyzing the triceps brachii and biceps femoris muscles, focusing on fiber morphology, myosin heavy chain (MYH) isoform distribution, and nuclei per fiber. A total of 12 dogs, divided equally into working and companion breed groups, were used in this study. Muscle samples were collected post-mortem and prepared for histological analysis using cryosectioning. Immunohistochemical staining was employed to identify the expression of MYH isoforms, including MYH2, MYH4, and MYH7, which correspond to type IIa, IIb, and type I fibers, respectively. The results demonstrated significant differences between the two breed groups. Working dogs exhibited larger muscle fibers, a higher proportion of type IIa (MYH2) and type I (MYH7) fibers, and a greater number of nuclei per fiber, suggesting adaptations for endurance and strength. In contrast, companion dogs showed a higher proportion of type IIb (MYH4) fibers, indicative of their capacity for short bursts of activity rather than sustained exertion. Companion breeds also displayed a higher fiber density but fewer nuclei per fiber, which may contribute to slower muscle regeneration. These findings may provide insights into the muscle adaptations of dogs based on their breed-specific functional demands and highlight the importance of considering these differences in veterinary care and rehabilitation. The study underscores the influence of selective breeding on muscle structure and function in dogs and suggests further research into breed-specific muscle recovery mechanisms. [ABSTRACT FROM AUTHOR]

The utilization of botulinum neurotoxin in the field of body contouring is on the rise. Body contouring procedures typically focus on specific muscle groups such as the superior trapezius, deltoid, and lateral head of the triceps brachii. The authors propose identifying optimal injection sites for botulinum neurotoxin to achieve desired aesthetic contouring of the shoulders and arms. The authors conducted a modified Sihler's staining method on specimens of the superior trapezius, deltoid, and lateral head of the triceps brachii muscles, totaling 16, 14, and 16 specimens, respectively. The neural distribution exhibited the most extensive branching patterns within the horizontal section (between 1/5 and 2/5) and the vertical section (between 2/4 and 4/4) of the superior trapezius muscle. In the deltoid muscle, the areas between the anterior and posterior deltoid bellies, specifically within the range of the horizontal 1/3 to 2/3 lines, showed significant intramuscular arborization. Furthermore, the middle deltoid muscle displayed arborization patterns between 2/3 and the axillary line. Regarding the triceps brachii muscle, the lateral heads demonstrated arborization between 4/10 and 7/10. The authors recommend targeting these regions, where maximum arborization occurs, as the optimal and safest points for injecting botulinum toxin. [ABSTRACT FROM AUTHOR]

Introduction: the muscular response on the main muscles of the propulsive phase of the upper limb in the crawl swimming style has been evaluated by means of tensiomyography (TMG), which was carried out through three parameters: activation time (Td), contraction time (Tc) and maximum deformation (Dm).The aim of this study is to evaluate the hypothesis of changes produced between lactic resistance training with passive rest and lactic resistance training with active rest. Material and methods: experimental study with ninety swimmers in the crawl stroke, with a mean age of 20 years. The session with passive recovery and the session with active recovery presented results with significant changes after the development of each of them in the Tc in the three muscles analysed, being in the Pectoralis Major (PM), p = 0.001, in the Latissimus Dorsi (LD), p = 0.01 and in the Tríceps Brachii (TB), p = 0.047. Conclusion: According to the results it can be deduced that lactic resistance training with passive rest and with active rest do not influence the muscle response if we compare both trainings. Only one of the Tc values changes, while the latissimus dorsi muscle also shows changes in Td.

Objective: The objective of this study was to investigate the impact of dietary deficiency and supplementation of calcium, zinc, copper, cobalt, manganese or selenium on minerals content in the longissimus dorsi (LD), biceps femoris (BF) and triceps brachii (TB) of grazing Mongolian sheep. Methods: We randomly divided 98 sheep into 7 treatment groups and fed them specific diets for 60 days: a total mineral nutrition diet (LCG), a calcium deficiency diet (LCa), a zinc deficiency diet (LZn), a copper deficiency diet (LCu), a cobalt deficiency diet (LCo), amanganese deficiency diet (LMn) and a selenium deficiency diet (LSe). Then 7 sheep from each group were slaughtered and samples of LD, BF and TB were collected for mineral content analysis. The remaining sheep in each group were subsequently fed specific diets for an additional 41 days: a totalmineral nutrition diet (SCG), a calciumsupplementation diet (SCa), a zinc supplementation diet (SZn), a copper supplementation diet (SCu), a cobalt supplementation diet (SCo), a manganese supplementation diet (SMn) and a selenium supplementation diet (SSe). Afterward, all sheep were slaughtered, and muscle samples were collected and analyzed. Results: Significant findings emerged that LCa decreased sulfur (S) content in BF and increased Ca content in LD and BF, while SCa increased S and Ca content in BF and TB, respectively (P<0.05). LZn decreased Zn, S, and potassium(K) content in LD and BF, while SZn increased Zn and S content in LD and BF, respectively (P < 0.05). LCu decreased Cu and iron (Fe) content in LD and TB, while SCu increased Fe content in TB (P < 0.05). LCo decreased phosphorus, S, K, Ca, Mn, Fe, Cu, and Zn content in LD (P < 0.05). LMn decreased Mn content and increased K content in TB, while SMn decreased K content in BF and TB (P < 0.05). LSe and SSe decreased and increased Se content in LD, BF, and TB, respectively (P < 0.05). Conclusion: Dietary mineral levels have varying effects on lamb meat minerals content. It is important to ensure an adequate intake of minerals in the diet to enhance the mineral nutrition of lamb meat. [ABSTRACT FROM AUTHOR]

Restoration of finger extension in mutilating hand injuries is crucial for restoring prehension and independent use of the hand. Patients often express desire to restore finger extension once finger flexion is achieved. However, the extensive forearm injury precludes use of any of conventional donors like the wrist or finger flexors for transfer to restore finger extension. Two patients with sequelae of mangled forearm injuries, underwent biceps and long head of triceps transfer to the finger extensors to improve opening up of the fingers. We discuss the treatment considerations while planning these transfers and provide the technical details, rehabilitation and outcome of these patients. Both the patients expressed dramatic improvement of their hand function and were satisfied with the outcome. Biceps and long head of triceps could serve as an effective second-line donor for restoration of finger extension when the conventional donors are not available. Level of Evidence: Level V (Therapeutic) [ABSTRACT FROM AUTHOR]

Despite the perceived importance of antagonist muscle activity, it is unknown if motor unit (MU) behavior at recruitment differs when a muscle acts as an antagonist versus agonist. Fourteen healthy participants performed ramped, isometric elbow flexor or extensor contractions to 50% or 100% maximal voluntary contraction (MVC) torque. Surface and fine-wire intramuscular electromyographic (EMG) recordings were sampled from biceps and triceps brachii. During agonist contractions, low-threshold MUs (recruited at <10% MVC torque) were sampled in all participants, with a total of 107 and 90 for biceps and triceps brachii, respectively. For ramped MVCs, antagonist surface EMG coactivation (% amplitude during agonist MVC) was 8.3 ± 6.6% for biceps and 15.2 ± 7.3% for triceps brachii. However, antagonist single MU activity was recorded from only four participants, with only one of these individuals having antagonist MUs recorded from both muscles. All antagonist MUs were successfully detected during agonist contractions, but many (~40%) had a recruitment threshold >10% MVC torque. For MUs recorded during both agonist and antagonist contractions, discharge rate at recruitment was seemingly lower for antagonist than agonist contractions. Coexistence of typical levels of surface EMG-derived coactivation with scant antagonist MU recordings suggests that coactivation in these muscles is primarily the result of cross talk. Based on the limited antagonist MU data detected, MUs recruited early during an agonist contraction are not necessarily among those first recruited during an antagonist contraction. These findings highlight the possibility of a modification of orderly recruitment when a motoneuron pool is acting as an antagonist. [ABSTRACT FROM AUTHOR]

Background: The radial groove is known as a sulcus on the posterior humerus and protects the radial nerve from adjacent muscle and soft tissue. In the literature, there exists heterogeneity regarding the presence of an actual radial groove and the radial nerve's interaction with the periosteum of the humerus. This study aimed to determine if there is a real radial groove, "sulcus," and define the relationship between the radial nerve and the periosteum of the posterior humerus. Methods: Eighteen fresh-frozen cadaveric specimens were dissected using a posterior triceps splitting approach. The radial nerve's interaction with the periosteum of the humerus was determined. The presence of a visible and palpable radial groove was also examined. Results: In 56% of specimens, the radial nerve was directly seated over the periosteum of the posterior humerus (direct contact between the nerve and bone). In comparison, 44% of specimens had a layer of the medial head of the triceps brachii muscle fibers interposition between the nerve and bone. 89% of specimens had no visible or palpable radial groove. In 11% of specimens, there was mild palpable depression. Conclusion: This study shows that the radial groove may not exist and is probably not a true anatomical structure. In addition, the nerve is in direct contact with the posterior periosteum of the humerus in most specimens. These anatomic relationships and findings add to the anatomical understanding of the radial nerve, which helps during operative approaches and fixation of the humerus. [ABSTRACT FROM AUTHOR]

The magnitude and duration of muscle force production are influenced by the fiber type proportion. In this work, surface electromyography (sEMG) signals of muscles with varied fiber type proportions, are generated. For this, relevant components of existing models reported in various literature have been adopted. Also, a method to calculate the motor unit size factor is proposed. sEMG signals of adductor pollicis (AP) and triceps brachii (TB) muscles are simulated from the onset of force production to muscle fatigue state at various percentages of maximal voluntary contraction (MVC) values. The model is validated using signals recorded from these muscles using well-defined isometric exercise protocols. Root mean square and mean power spectral density values extracted from the simulated and recorded signals are found to increase for TB and decrease for AP with time. A linear variation of the features with %MVC values is obtained for simulated and experimental results. The Bland-Altman plot is used to analyze the agreement between simulated and experimental feature values. Good agreement is obtained for the feature values at various %MVCs. The mean endurance time calculated using the model is found to be comparable to that of the experimental value. This method can be used to generate sEMG signals of different muscles with varying fiber type ratios under various neuromuscular conditions. [ABSTRACT FROM AUTHOR]

Targeted muscle strengthening might improve performance or help overcome training stagnation; therefore, the aim of the present study was to investigate changes in muscle activity patterns before and after six weeks of targeted resistance training. Twenty-seven resistance-trained men were divided into three groups according to their prime mover activity, as measured by surface electromyography during a bench press (BP). Each group underwent a six-week block of targeted exercises for one of the following muscles: anterior deltoid (AD), pectoralis major (PM) or triceps brachii (TB). ANOVA showed that each group increased their 1 repetition maximum (1RM) (p < 0.05) and the activity of the exercised muscle group during an isometric bench press (p < 0.01) and during a dynamic bench press (p < 0.01) at 85% of the 1RM. During the isometric BP, the TB training group had an increase in TB activity in comparison to the other groups. Targeted muscle training is a useful method for muscle activity increase and increasing the maximum strength in complex exercise, when applied in activity-deficient muscle groups. Strengthening the TB elicits changes in all prime movers and results in TB activity domination during a bench press. [ABSTRACT FROM AUTHOR]

Simple Summary: Chimpanzees and humans are both species of hominoid primates that are closely related phylogenetically. One of the key differences between these two species is their use of their upper extremities. Humans use this limb mainly in manipulative tasks, while chimpanzees also use it during locomotion. In this study, we have analyzed the muscle architecture and the expression of the myosin heavy chain isoforms in the two elbow extensor muscles, the triceps brachii and the anconeus, in humans and chimpanzees, in order to find differences that could be related to the different uses of the upper extremities in these species. We have found that the triceps brachii of chimpanzees is more prepared for strength and power as an adaptation to locomotion, while the same muscle in humans is more prepared for speed and resistance to fatigue as an adaptation to manipulative activities. Our results increase the knowledge we have of the musculoskeletal system of chimpanzees and can be applied in various fields, such as comparative anatomy, evolutionary anatomy or anthropology. The anatomical and functional characteristics of the elbow extensor muscles (triceps brachii and anconeus) have not been widely studied in non-human hominoid primates, despite their great functional importance. In the present study, we have analyzed the muscle architecture and the expression of the myosin heavy chain (MHC) isoforms in the elbow extensors in humans and chimpanzees. Our main objective was to identify differences in these muscles that could be related to the different uses of the upper extremity in the two species. In five humans and five chimpanzees, we have analyzed muscle mass (MM), muscle fascicle length (MFL), and the physiological cross-sectional area (PCSA). In addition, we have assessed the expression of the MHC isoforms by RT-PCR. We have found high MM and PCSA values and higher expression of the MHC-IIx isoform in the triceps brachii of chimpanzees, while in humans, the triceps brachii has high MFL values and a higher expression of the MHC-I and MHC-IIa isoforms. In contrast, there were no significant differences between humans and chimpanzees in any of the values for the anconeus. These findings could be related to the participation of the triceps brachii in the locomotion of chimpanzees and to the use of the upper extremity in manipulative functions in humans. The results obtained in the anconeus support its primary function as a stabilizer of the elbow joint in the two species. [ABSTRACT FROM AUTHOR]

Background: Tricipital aponeurosis (TA) has gained attraction as a constant and reliable landmark to identify the location of radial nerve in the setting of fracture distal humeri. The aponeurosis itself shows variant anatomical patterns. In this study, we intend to provide a comprehensive description and functional classification of observed anatomical variations with possible clinical implications. Materials and methods: Sixty arms belonging to 30 adult cadavers were studied. TA was examined grossly to document variations in its shape and classified accordingly. Subsequently, length and breadth of TA were measured. The distance of the radial nerve (RN) from the point of confluence and from the lateral border of TA was also measured (tricepso-radial distance [TRD]). These distances were correlated with the different patterns of TA obtained. Results: Based on the shape of the proximal apex of TA or point of confluence and frequency of their occurrence, we propose a new classification of 4 patterns for the TA anatomy. Pattern I: classically seen as the triangular proximal apex (76.67%); pattern II: tongue shaped or blunt proximal apex (18.33%); pattern III: bifurcated or dual proximal apex (3.33%); pattern IV: as the absence of TA (1.67%). The mean of length and breadth of TA was 16.58 ± 2.05 cm and 3.61 ± 0.61 cm, respectively. The mean distance of RN from point of confluence and lateral border of TA was 3.57 ± 0.19 cm and 2.04 ± 0.56 cm, respectively. The length, breadth of TA and TRD differs amongst the different patterns of TA. Conclusions: Anatomical variations in the shape and size of TA are frequently encountered. The proposed, hitherto undescribed, classification may make operating surgeon aware of these morphological variations and help prevent iatrogenic injury to RN. Such classification is simple and unique; however, its success relies upon universal acceptance. [ABSTRACT FROM AUTHOR]

Although many textbooks reported the innervation of three heads of the triceps muscle with the radial nerve, some studies showed the axillary nerve supply to this muscle. Herein, we report a 21-year-old male patients with a traumatic injury to the axillary nerve associated with paralysis of his triceps muscle. Based on the electrophysiological findings, it could be reasonable to conclude that the main branch innervating all heads of the triceps muscle originated from the axillary nerve. It is vital to look for concomitant paralysis of the triceps in patients with an axillary nerve injury in terms of surgical management, prognosis, and nerve repair. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to determine the position where the most activated and isolated individual muscles were. In the next steps, the selected limb positions will be used to determine the maximum values of isometric forces of the individual muscle heads based on the Hill model. Methods: In order to determine the sought muscle activation, an electromyograph was used. Isometric contraction measurements were carried out for seven series of tests. Isometric contraction was performed as 100% MVC. Results: For the long head of the biceps muscle, in the case of bending in the shoulder joint, angle of 75° was selected and for abduction in the shoulder joint -- 90°. Internal rotation in the shoulder joint was omitted because of lower activation values. For the short head of the biceps muscle, the angle characterized by the greatest activity of the head was the angle of 115° in flexion at the elbow joint. The selected angle was 30° for shoulder extension and 110° for shoulder adduction. For the lateral head of the triceps brachial muscle, measurements showed that the angle at which the lateral head was most activated is 115°. Conclusions: The aim of this study was to determine the positions of the arm muscles that activate and isolate individual heads the most. The research presented and achieved results concern one specific person for whom a personalized numerical model was developed to represent the flexion-extension movement at the elbow joint. The performed tests can also be a preliminary assessment of the upper limb positions, for which wider conclusions could be drawn in the case of measurements on a larger number of participants. [ABSTRACT FROM AUTHOR]

To characterize the scapular pitching biomechanics in symptomatic GIRD pitchers (SG) compared to asymptomatic GIRD (ASG) and healthy pitchers. The scapular kinematics and associated muscle activities during pitching were recorded in 33 high school pitchers. Compared to healthy, GIRD pitchers had less scapular posterior tilt in each pitching event (average difference, AD=14.4°, p<0.01) and ASG demonstrated less scapular upward rotation at ball release (AD=12.8°, p<0.01) and greater muscle activity in the triceps brachii in the early-cocking phase (AD=9.9%, p=0.015) and in the serratus anterior in the late-cocking phase (AD=30.8%, p<0.01). Additionally, SG had less muscular activity on triceps brachii in the acceleration phase and serratus anterior in the cocking phase (AD=37.8%, p=0.016; AD=15.5%, p<0.01, respectively) compared to ASG. GIRD pitchers exhibited less scapular posterior tilt during pitching, which may cause impingement. Since tightness of the anterior shoulder is a common cause of inadequacy of posterior tilt during arm elevation, stretching exercise of the anterior shoulder is recommended. Given the inadequate recruitment during pitching in the GIRD pitchers, symptoms may develop following potential impingement. [ABSTRACT FROM AUTHOR]

Introduction Triceps brachii muscle is the only muscle of posterior compartment of arm, consisting of three heads—long, lateral, and medial. Radial nerve and profunda brachii artery run in the radial groove that separate lateral and medial head. Evolutionarily, triceps has many subheads which either fused or disappeared. Therefore, the knowledge of muscle is essential anthropologically and clinically, and this study aims to study the anatomical variations of triceps brachii muscle. Case Report In the present case, during routine dissections of undergraduate MBBS students, a fourth head of origin of triceps brachii muscle was seen in a male cadaver in the right arm. The variation was seen only unilaterally in cadaver. The origin was tendinous arising from the posteromedial aspect of upper part of the shaft of the humerus close to the surgical neck above the radial groove. This tendon was arching over the neurovascular bundle containing radial nerve and profunda brachii artery. Discussion and Conclusion The variations of triceps brachii muscles are mentioned in literature but are uncommon and if tendinous fourth head is present over the neurovascular bundles, it may lead to compression syndrome. Hence, these variations are of great importance to the radiologists, surgeons, and orthopaedicians while dealing with posterior compartment of arm.

BACKGROUND: Passive stiffness of muscle is the basic data to guide the research and development of tissue engineering materials, injury transplantation and repair. However, the previous experimental data, such as material research and development, are mostly from animals, and there are few reports on the mechanical properties of human skeletal muscle. By comparing and analyzing the biomechanical properties of adult and pig flexor and extensor muscles, it provides basic human body data for the development of bionic material. OBJECTIVE: To evaluate the biomechanical properties of adult biceps and triceps muscularis under real-time dynamic stretching, and compare them with pig foreleg flexors and extensors to explore the biomechanical differences between human materials and animal materials. It provides reference for research and development of a bionic material. METHODS: The test specimens were taken from fresh forelegs of 10 pigs and 6 specimens of human upper limbs, and dissected along the direction of muscle fibers to obtain the largest flexors and extensors of the forelegs of pigs, as well as human biceps and triceps. Samples were sectioned to 10 mm thick, 10 mm wide, 50 mm long and nine black spots were marked on the surface of the sample for the quasi-static tensile testing. The optical non-contact method was adopted to calculate the distance change between the labeled points, measure the strain, and calculate the stress response. RESULTS AND CONCLUSION: The internal strain of biceps brachii, triceps brachii, flexor muscle and extensor muscle showed uneven distribution during stretching. Triceps brachii, biceps brachii and flexor Cauchy stress-strain showed a nonlinear “S”-type increase. The Cauchy stress-strain of extensor muscle increased linearly. When draw ratio >1.2, under the same strain, the stress of human muscle was much higher than pig muscle. For analysis of variance F=2 870.346, there was statistical significance between pairings of four kinds of muscles (P < 0.001). Under real-time dynamic stretching, there were statistically significant differences in the biomechanical properties of the maximum flexor and extensor muscles of the forelegs of pigs and adult biceps and triceps. The stiffness in descending order was the biceps brachii, triceps brachii, pig flexor, and pig extensor. The flexor stiffness of human rump is greater than that of extensor muscle. [ABSTRACT FROM AUTHOR]

Introduction/Aims: Hypertrophic triceps brachii contributes to ulnar nerve movement, but the location of the mass effect of the triceps brachii muscle is not known. In this study we aimed to determine the mass effect of the distal medial head of the triceps brachii (DMTB) muscle on ulnar nerve movement. Methods: In 48 arms, movement of the ulnar nerve at the medial epicondyle and muscle thickness (medial and long head of the triceps brachii [MLTB], medial head of the triceps brachii [MTB], DMTB, and biceps brachii [BB]) were measured using ultrasonography. Results: Ulnar nerve movement at the elbow was consistently correlated with the DMTB muscle thickness (horizontal ulnar nerve movement at the elbow [HM] / vertical ulnar nerve movement at the elbow [VM] with 90° elbow flexion: r = 0.668 / r = 0.313, HM/VM with full elbow flexion: r = 0.481 / r = 0.391). With multiple linear regression, the DMTB was the most important muscle with regard to contribution of thickness to ulnar nerve movement. Individuals with partial and complete dislocation showed a thicker DMTB than those without dislocation. Discussion Our data suggest that the mass effect of the triceps brachii muscle is exerted primarily by its distal portion. When ulnar nerve dislocation is observed, thickness and anatomical variation of DMTB in the retrocondylar area during elbow flexion should be assessed. [ABSTRACT FROM AUTHOR]

Introduction: The medial head of the triceps brachii flap is already described as a local muscular or as a free flap. It allows coverage of defects of the posterior cubital region. The aim of this study was to describe the vascular anatomy of the musculocutaneous medial triceps brachii pedicled flap. Methods: Eleven fresh–frozen upper limbs (6 come from women and 5 from men) were proximally injected with Indian ink agar solution. The medial head of the triceps brachii muscle was dissected and the superior ulnar collateral artery (SUCA) was isolated with its collaterals. The collateral arteries were dissected to determine whether there were septocutaneous or musculocutaneous arteries for vascularization of the skin in front of the medial head. Lengths of those collaterals arteries were measured. Results: The average number of collaterals arteries from the SUCA supplying the medial head of the triceps brachii is 4.5 (from 3 to 6 arteries). Among these collaterals' arteries, there are one average 1.5 (0.6–4.5) septocutaneous arteries and 3 (1–4.8) musculocutaneous arteries. Discussion and conclusion: A musculocutaneous flap with the medial head of the triceps brachii muscle can be described with the muscle. The SUCA gives perforator arteries musculocutaneous and septocutaneous for the vascularization of the triceps brachii medial head. The use of local pedicled flap with similar tissue maximizes healing with a minimal morbidity of the donor site. This study demonstrated the feasibility of the medial head triceps brachii musculocutaneous flap to cover defect of the posterior aspect of the elbow. [ABSTRACT FROM AUTHOR]

Objective: The bench press is a resistance training exercise that targets several upper body muscles, including the pectoralis major (PM), anterior deltoid (AD), and triceps brachii (TB). The purpose of this study was to influence the PM activity pattern during the bench press after a 10-week targeted resistance training intervention., Methods: Sixteen men with significant experience in strength training participated in this study. They were divided into two groups: experimental and control. The experimental group underwent targeted training of PM and bench press, while the control group only did bench press. Electromyography (EMG) was used to assess muscle activity before and after the intervention., Results: The experimental group had a significant increase in PM activity after the intervention (p=0.0002; ES=2.6), while the control group did not show any significant change (p=0.14). The activity of AD and TB remained relatively stable across both groups and time points., Conclusions: These findings indicate that focused resistance training can improve PM involvement in the bench press, potentially optimizing muscle excitation patterns and performance., Competing Interests: The authors have no conflict of interest.

To systematically review the effects of exercise on fascicle geometry and muscle size parameters of the upper extremity muscles, the CENTRAL, CINAHL, PubMed and OpenGrey databases were searched on 31 July 2021. Finally, 17 randomised controlled trials (RCTs) were included in this systematic review. High-intensity bench press training (g = 1.03) and 12 RM bench press exercises (g = 1.21) showed a large effect size on increasing pectoralis major muscle size. In the elbow extensors, large effects were reported for an increase in muscle size with isometric maximal voluntary co-contraction training (g = 1.97), lying triceps extension exercise (g = 1.25), and nonlinear periodised resistance training (g = 2.07). In addition, further large effects were achieved in the elbow flexors via traditional elbow flexion exercises (g = 0.93), concentric low-load forearm flexion-extension training (g = 0.94, g = 1), isometric maximal voluntary co-contraction training (g = 1.01), concentric low-load forearm flexion-extension training with blood flow restriction (g = 1.02, g = 1.07), and nonlinear periodised resistance training (g = 1.13, g = 1.34). Regarding the forearm muscles, isometric ulnar deviation training showed a large effect (g = 2.22) on increasing the flexor carpi ulnaris and radialis muscle size. Results show that these training modalities are suitable for gaining hypertrophy in the relevant muscles with at least four weeks of training duration. Future RCTs should investigate the effects of exercise modalities on the triceps brachii fascicle geometry, the infraspinatus muscle thickness (MT) and the subscapular MT due to their associations with sports performance. [ABSTRACT FROM AUTHOR]

Recent studies have reported that resistance training increases the cross-sectional areas (CSAs) of tendons; however, this finding has not been consistently observed across different studies. If tendon CSA increases through resistance training, resistancetrained individuals should have larger tendon CSAs as compared with untrained individuals. Therefore, in the current study, we aimed to investigate whether resistance training increases tendon CSAs by comparing resistance-trained and untrained individuals. Sixteen males, who were either body builders or rugby players, were recruited as the training group, and 11 males, who did not participate in regular resistance training, were recruited into the control group. Tendon CSAs and muscle volumes of the triceps brachii, quadriceps femoris, and triceps surae were calculated from images obtained by using magnetic resonance imaging. The volumes of the 3 muscles were significantly higher in the training group than in the control group (P < .001 for all muscles). However, a significant difference in tendon CSAs was found only for the distal portion of the triceps surae tendon (P - .041). These findings indicate that tendon CSA is not associated with muscle volume, suggesting that resistance training does not increase tendon CSA. [ABSTRACT FROM AUTHOR]

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Introduction: Little is known about potential differences in contractile properties of muscle fibers of the same type in arms and legs. Accordingly, the present study was designed to compare the force-generating capacity and Ca2+ sensitivity of fibers from arm and leg muscles of highly trained cross-country skiers. Method: Single muscle fibers of m. vastus lateralis and m. triceps brachii of eight highly trained cross-country skiers were analyzed with respect to maximal Ca2+-activated force, specific force and Ca2+ sensitivity. Result: The maximal Ca2+-activated force was greater for myosin heavy chain (MHC) II than MHC I fibers in both the arm (+62%, P < 0.001) and leg muscle (+77%, P < 0.001), with no differences between limbs for each MHC isoform. In addition, the specific force of MHC II fibers was higher than that of MHC I fibers in both arms (+41%, P = 0.002) and legs (+95%, P < 0.001). The specific force of MHC II fibers was the same in both limbs, whereas MHC I fibers from the m. triceps brachii were, on average, 39% stronger than fibers of the same type from the m. vastus lateralis (P = 0.003). pCa50 was not different between MHC I and II fibers in neither arms nor legs, but the MHC I fibers of m. triceps brachii demonstrated higher Ca2+ sensitivity than fibers of the same type from m. vastus lateralis (P = 0.007). Conclusion: Comparison of muscles in limbs equally well trained revealed that MHC I fibers in the arm muscle exhibited a higher specific force-generating capacity and greater Ca2+ sensitivity than the same type of fiber in the leg, with no such difference in the case of MHC II fibers. These distinct differences in the properties of fibers of the same type in equally well-trained muscles open new perspectives in muscle physiology. [ABSTRACT FROM AUTHOR]

Background: Knowledge of potential compression sites of peripheral nerves is important to the clinician and surgeon alike. One anatomical location for potential compression of the radial nerve, which is rarely mentioned in the literature, is at the proximal humeral attachment of the lateral head of the triceps brachii at the level of the proximal spiral groove. As no anatomical studies have been devoted to this band, the present study was conducted. Methods: Ten adult fresh-frozen cadavers were dissected and the lateral head's attachment onto the posterior humerus evaluated for a band. This anatomy and its relation to the radial nerve during range of motion of the elbow and forearm were evaluated. Results: A band was found on 15 of 20 arms. On five sides, the band was comprised of grossly muscle fibers of the lateral head of the triceps brachii and was not tendinous. The bands were crescent-shaped, straight, and duplicated on nine, five, and one arm, respectively. The length of the bands ranged from 1.1 to 2.2 cm (mean 1.54 cm). The width of the bands ranged from 0.5 to 1.1 cm (mean 0.8 cm). With elbow extension and the forearm in neutral, all bands were lax. With elbow extension and the forearm supinated, the bands became tauter less the muscular bands. In elbow extension and with the forearm in supination, the bands became most taut less the muscular bands. Conclusions: The presence of a fibrous band extending from the lateral head of the triceps brachii is common and should be among the differential diagnoses of anatomical sites for potential proximal radial nerve compression when other more common locations are ruled out. [ABSTRACT FROM AUTHOR]

Neuromuscular fatigue evaluation is widely performed on different muscles through the conventional protocol using maximum voluntary contraction (MVC) with electrical stimuli in the analyzed muscle. In an attempt to use this protocol on elbow extensor musculature, previous studies and pilot studies showed co-contraction effects from antagonist musculature during muscular stimulations. The aim of this study was to propose a new neuromuscular fatigue protocol evaluation on elbow extensor musculature. Twenty participants preformed exercises to induce central (CenFat) and peripheral fatigue (PerFat). Neuromuscular fatigue was evaluated on knee extensor muscles by a conventional protocol that provides Twitch Superimposed (TSK) and Twitch Potentiated (TPK), central and peripheral parameters respectively. For elbow extensor muscles, the protocol used sustained submaximal contraction at 10, 20, 30, 40, and 50% of MVC. The neuromuscular fatigue in upper limbs was identified by Twitch Potentiated (TPE) and multiple Twitch Superimposed (TSE) parameters. Using the relationship between MVC (%) and evoked force, the proposed protocol used several TSE to provide slope, y-intercept and R2. It is proposed that slope, R2, and y-intercept change may indicate peripheral fatigue and the identified relationship between y-intercept and R2 may indicate central fatigue or both peripheral and central fatigue. The results were compared using the non-parametric analyzes of Friedmann and Wilcoxon and their possible correlations were verified by the Spearmann test (significance level set at p < 0.05). After PerFat a decrease in TPE (57.1%, p < 0.001) was found but not in any TSE, indicating only peripheral fatigue in upper limbs. After CenFat a decrease in TPE (21.4%, p: 0.008) and TPK (20.9%, p < 0.001) were found but not in TSK, indicating peripheral fatigue in upper and lower limbs but not central fatigue. A non-significant increase of 15.3% after CenFat and a statistical reduction (80.1%, p: 0.001) after PerFat were found by slope. Despite R2 showing differences after both exercises (p < 0.05), it showed a recovery behavior after CenFat (p: 0.016). Although PerFat provided only peripheral fatigue, CenFat did not provide central fatigue. Considering the procedural limitations of CenFat, parameters resulting from the proposed protocol are sensitive to neuromuscular alteration, however, further studies are required.

Individuals with Parkinson's disease (PD) demonstrate deficits in muscle activation such as decreased amplitude and inappropriate bursting. There is evidence that some of these disturbances are more pronounced in extensor vs. flexor muscles. Surface EMG has been used widely to quantify muscle activation deficits in PD, but analysis of discharge of the underlying motor units may provide greater insight and be more sensitive to changes early in the disease. Of the few studies that have examined motor unit discharge in PD, the majority were conducted in the first dorsal interosseous, and no studies have measured motor units from extensor and flexor muscles within the same cohort. The objective of this study was to characterize the firing behavior of single motor units in the elbow flexor and extensor muscles during isometric contractions in people with mild-to-moderate PD. Ten individuals with PD (off-medication) and nine healthy controls were tested. Motor unit spike times were recorded via intramuscular EMG from the biceps and triceps brachii muscles during 30-s isometric contractions at 10% maximum voluntary elbow flexion and elbow extension torque, respectively. We selected variables of mean motor unit discharge rate, discharge variability, and torque variability to evaluate motor abnormalities in the PD group. The effects of group, muscle, and group-by-muscle on each variable were determined using separate linear mixed models. Discharge rate and torque variability were not different between groups, but discharge variability was significantly higher in the PD group for both muscles combined (p < 0.0001). We also evaluated the asymmetry in these motor variables between the triceps and biceps for each individual participant with PD to evaluate whether there was an association with disease severity. The difference in torque variability between elbow flexion and extension was significantly correlated with both the Hoehn and Yahr scale (rho = 0.71) and UPDRS (rho = 0.62). Our findings demonstrate that variability in motor output, rather than decreased discharge rates, may contribute to motor dysfunction in people with mild-to-moderate PD. Our findings provide insight into altered neural control of movement in PD and demonstrate the importance of measuring from multiple muscles within the same cohort.

Study aim: The aim of the present study was to examine a single movement of dynamic stretching (SMDS) of the shooting arm as a pre-shot routine for free throw performance (FTP).

Neuromuscular fatigue evaluation is widely performed on different muscles through the conventional protocol using maximum voluntary contraction (MVC) with electrical stimuli in the analyzed muscle. In an attempt to use this protocol on elbow extensor musculature, previous studies and pilot studies showed co-contraction effects from antagonist musculature during muscular stimulations. The aim of this study was to propose a new neuromuscular fatigue protocol evaluation on elbow extensor musculature. Twenty participants preformed exercises to induce central (CenFat) and peripheral fatigue (PerFat). Neuromuscular fatigue was evaluated on knee extensor muscles by a conventional protocol that provides Twitch Superimposed (TSK) and Twitch Potentiated (TPK), central and peripheral parameters respectively. For elbow extensor muscles, the protocol used sustained submaximal contraction at 10, 20, 30, 40, and 50% of MVC. The neuromuscular fatigue in upper limbs was identified by Twitch Potentiated (TPE) and multiple Twitch Superimposed (TSE) parameters. Using the relationship between MVC (%) and evoked force, the proposed protocol used several TSE to provide slope, y-intercept and R 2. It is proposed that slope, R 2, and y-intercept change may indicate peripheral fatigue and the identified relationship between y-intercept and R 2 may indicate central fatigue or both peripheral and central fatigue. The results were compared using the non-parametric analyzes of Friedmann and Wilcoxon and their possible correlations were verified by the Spearmann test (significance level set at p < 0.05). After PerFat a decrease in TPE (57.1%, p < 0.001) was found but not in any TSE, indicating only peripheral fatigue in upper limbs. After CenFat a decrease in TPE (21.4%, p : 0.008) and TPK (20.9%, p < 0.001) were found but not in TSK, indicating peripheral fatigue in upper and lower limbs but not central fatigue. A non-significant increase of 15.3% after CenFat and a statistical reduction (80.1%, p : 0.001) after PerFat were found by slope. Despite R 2 showing differences after both exercises (p < 0.05), it showed a recovery behavior after CenFat (p : 0.016). Although PerFat provided only peripheral fatigue, CenFat did not provide central fatigue. Considering the procedural limitations of CenFat, parameters resulting from the proposed protocol are sensitive to neuromuscular alteration, however, further studies are required. [ABSTRACT FROM AUTHOR]

Purpose: To investigate possible sex-related differences in group III/IV muscle afferent feedback with isometric fatigue, we aimed to assess the effect of a sustained submaximal elbow extensor contraction on motoneuronal excitability (cervicomedullary motor evoked potential [CMEP]) and voluntary activation (VA). Methods: Twenty-four participants (12 females) performed a 15-min contraction at the level of EMG activity recorded at 15% of maximal torque. Each minute, CMEP were elicited by cervicomedullary stimulation with and without conditioning transcranial magnetic stimulation (TMS) delivered 100 ms earlier. Unconditioned and conditioned motor evoked potentials (MEP) in response to TMS were also recorded to assess motor cortical excitability. CMEP and MEP were normalized for changes in downstream excitability and expressed as percentage of their prefatigue (control) values. Postfatigue, VA was calculated from superimposed and resting tetani evoked by stimulation over triceps brachii. Results: Males were twice as strong as females, but the sexes did not differ for any variable during the fatigue protocol. On a 0–10 scale, RPE increased from ~2.5 to 9. The unconditioned CMEP did not change, whereas the conditioned CMEP was reduced by ~50%. By contrast, the unconditioned and conditioned MEP increased to ~200% and ~320% of the control values, respectively. At task termination, maximal torque was reduced ~40%, and VA was ~80%, down from a prefatigue value of ~96%. Conclusions: Results support the scant published data on the elbow extensors and indicate no sex-related differences for isometric fatigue of this muscle group. The motoneuronal and VA data suggest that metabolite buildup and group III/IV muscle afferent activity were similar for females and males. [ABSTRACT FROM AUTHOR]

Background. The purpose was to analyze the prevalence, origin, course and termination of the ulnar collateral nerve in anatomical samples from Indian population. Methods. The present study included 68 adult human cadaveric embalmed upper limbs. The sex of these upper limbs were not known. The initial segment of radial nerve was meticulously dissected in the specimens to observe the ulnar collateral nerve. The digital Vernier caliper was used for the measurements which were performed in this study. The data was given in millimeter and expressed as mean ± SD. Results. The ulnar collateral nerve was observed in 57 (83.8%) of our specimens. It originated in the axilla in 35 cases (61.4%), at the brachio-axillary angle in 13 (22.8%) and in the arm in 9 cases (15.8%) respectively. The termination of ulnar collateral nerve by piercing deep into the triceps muscle happened 101.9 ± 4 mm above the medial epicondyle of humerus. The origins of muscular branch to long head of triceps muscle and ulnar collateral nerve were located 44.7 ± 3.7 mm and 66.7 ± 4.4 mm away from the bifurcation of posterior cord respectively. Conclusions. The present study suggests higher frequency of ulnar collateral nerve in sample Indian population. Ulnar collateral nerve can be used to re-innervate the muscles in case of brachial plexus injuries. Our study provides information about the detailed morphology and topography of the ulnar collateral nerve. The detailed knowledge can help the orthopedic surgeons during the procedures like muscle transfer, nerve transfer and nerve grafting. [ABSTRACT FROM AUTHOR]

Individuals with Parkinson's disease (PD) demonstrate deficits in muscle activation such as decreased amplitude and inappropriate bursting. There is evidence that some of these disturbances are more pronounced in extensor vs. flexor muscles. Surface EMG has been used widely to quantify muscle activation deficits in PD, but analysis of discharge of the underlying motor units may provide greater insight and be more sensitive to changes early in the disease. Of the few studies that have examined motor unit discharge in PD, the majority were conducted in the first dorsal interosseous, and no studies have measured motor units from extensor and flexor muscles within the same cohort. The objective of this study was to characterize the firing behavior of single motor units in the elbow flexor and extensor muscles during isometric contractions in people with mild-to-moderate PD. Ten individuals with PD (off-medication) and nine healthy controls were tested. Motor unit spike times were recorded via intramuscular EMG from the biceps and triceps brachii muscles during 30-s isometric contractions at 10% maximum voluntary elbow flexion and elbow extension torque, respectively. We selected variables of mean motor unit discharge rate, discharge variability, and torque variability to evaluate motor abnormalities in the PD group. The effects of group, muscle, and group-by-muscle on each variable were determined using separate linear mixed models. Discharge rate and torque variability were not different between groups, but discharge variability was significantly higher in the PD group for both muscles combined (p < 0.0001). We also evaluated the asymmetry in these motor variables between the triceps and biceps for each individual participant with PD to evaluate whether there was an association with disease severity. The difference in torque variability between elbow flexion and extension was significantly correlated with both the Hoehn and Yahr scale (rho = 0.71) and UPDRS (rho = 0.62). Our findings demonstrate that variability in motor output, rather than decreased discharge rates, may contribute to motor dysfunction in people with mild-to-moderate PD. Our findings provide insight into altered neural control of movement in PD and demonstrate the importance of measuring from multiple muscles within the same cohort. [ABSTRACT FROM AUTHOR]

Previous studies demonstrated that the presence of neuromuscular fatigue within the triceps brachii muscle was accompanied by decreasing accuracy in throwing motion; however, sex differences in triceps brachii fatigability and throwing accuracy have not yet been investigated. The aim of the current study was to investigate the differences between female and male in measures of triceps brachii fatigability and basketball shooting accuracy after a fatiguing exercise. Twelve male (age, mean ± SD; 16.±1.4 yr) and twelve female (age, mean ± SD; 16 ± 1.2 yr) with no major medical history participated in the laboratory-based study. Basketball shooting accuracy, maximal voluntary contraction force and muscular endurance of the triceps brachii muscle measured before and after a fatiguing exercise. Maximal voluntary contraction force, endurance time of the triceps brachii muscle and basketball shooting accuracy significantly reduced after fatiguing exercise (P < 0.05), with a higher reduction identified for the male as compared to female (P < 0.05). The result suggests a significant effect of sex differences on triceps brachii fatigability and basketball shooting accuracy after fatiguing exercise, most likely due to sex differences in muscle fibre type composition. However, future research is required to confirm sex-specific differences in motor skill accuracy after fatiguing exercise. [ABSTRACT FROM AUTHOR]

Background: Push-up is considered as an excellent exercise for both assessment and training in athletes. However, the influence of its mode of application on activation of shoulder girdle musculature has been scantily studied by previous research in young overhead athletes. Objectives: To investigate the activity of pectoralis major (PM) and triceps brachii (TB) muscle during push-up exercise performed on the push-up bar and perfect push-up using shoulder width (SW), narrow shoulder width (NSW) and wide shoulder width (WSW) hand positions in young overhead athletes. Methods: 24 young overhead athletes were recruited for the present study. Surface electromyography (EMG) was recorded for the PM and the TB muscles during the performance of push-up exercise on the push-up bar and perfect push-up using different hand positions (SW, NSW, and WSW). Root mean square (RMS) of the EMG signal was analyzed during each variation of push-up exercise for both muscles. Muscle activity was calculated as percentage maximum voluntary isometric contraction (% MVIC). Results: EMG activity of PM muscle was significantly greater in WSW hand position as compared to SW (p < 0.01) and NSW (p < 0.01) hand position; whereas, the activity of TB was significantly greater in NSW hand position as compared to SW (p < 0.01) and WSW (p < 0.01) hand position. There were no significant differences in the EMG activity of PM (p = 0.54) and TB (p = 0.68) muscles between the push-up bar versus the perfect push-up. Conclusion: WSW hand position may be used during a push-up when the goal is to strengthen PM; whereas, an NSW hand position may be utilized for the selective strengthening of TB muscle. Both perfect push-up and push-up bar may be utilized by overhead athletes for performing push-ups based on the availability of equipment. [ABSTRACT FROM AUTHOR]

Introduction: teres major muscle of the scapular region, is located inferior to the teres minor. This connects the humerus bone with scapula posteriorly. This has anatomical importance of forming the intermuscular spaces and the clinical importance of repair of rotator cuff muscle tendons. Teres major muscle along with the latissmus dorsi, adducts and medially rotates the arm and assists in the extension of shoulder joint. The anatomical variation of teres major muscle is rarely documented. We have found the variation in teres major muscle insertion in a female cadaver on the left side, in which the said muscle merged with the triceps brachii and latissimus dorsi. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effects of changes in exercise intensity and speed on the three heads of the triceps brachii (TB) during triceps push-down exercise until task failure. Twenty-five subjects performed triceps push-down exercise at three different intensities (30, 45, and 60% 1RM) and speeds (slow, medium, and fast) until failure, and surface electromyography (sEMG) signals were recorded from the lateral, long and medial heads of the TB. The endurance time (ET), number of repetitions (NR) and rate of fatigue (ROF) were analyzed. Subsequently, the root-mean-square (RMS), mean power frequency (MPF) and median frequency (MDF) under no-fatigue (NF) and fatigue (Fa) conditions were statistically compared. The findings reveal that ROF increases with increase in the intensity and speed, and the opposite were obtained for the ET. The ROF in the three heads were comparable for all intensities and speeds. The ROF showed a significant difference (P < 0.05) among the three intensities and speeds for all heads. The three heads showed significantly different (P < 0.05) MPF and MDF values for all the performed exercises under both conditions, whereas the RMS values were significantly different only under Fa conditions. The current observations suggest that exercise intensity and speed affect the ROF while changes in intensity do not affect the MPF and MDF under Fa conditions. The behavior of the spectral parameters indicate that the three heads do not work in unison under any of the conditions. Changes in the speed of triceps push-down exercise affects the lateral and long heads, but changes in the exercise intensity affected the attributes of all heads to a greater extent.

The objective of this study was to investigate the effects of changes in exercise intensity and speed on the three heads of the triceps brachii (TB) during triceps push-down exercise until task failure. Twenty-five subjects performed triceps push-down exercise at three different intensities (30, 45, and 60% 1RM) and speeds (slow, medium, and fast) until failure, and surface electromyography (sEMG) signals were recorded from the lateral, long and medial heads of the TB. The endurance time (ET), number of repetitions (NR) and rate of fatigue (ROF) were analyzed. Subsequently, the root-mean-square (RMS), mean power frequency (MPF) and median frequency (MDF) under no-fatigue (NF) and fatigue (Fa) conditions were statistically compared. The findings reveal that ROF increases with increase in the intensity and speed, and the opposite were obtained for the ET. The ROF in the three heads were comparable for all intensities and speeds. The ROF showed a significant difference (P < 0.05) among the three intensities and speeds for all heads. The three heads showed significantly different (P < 0.05) MPF and MDF values for all the performed exercises under both conditions, whereas the RMS values were significantly different only under Fa conditions. The current observations suggest that exercise intensity and speed affect the ROF while changes in intensity do not affect the MPF and MDF under Fa conditions. The behavior of the spectral parameters indicate that the three heads do not work in unison under any of the conditions. Changes in the speed of triceps push-down exercise affects the lateral and long heads, but changes in the exercise intensity affected the attributes of all heads to a greater extent. [ABSTRACT FROM AUTHOR]

The current study examined the effects of a preceding bout of aerobic exercise (AE) on subsequent molecular signaling to resistance exercise (RE) of the elbow extensors. Eleven men performed unilateral elbow-extensor AE (~45 min at 70% peak workload) followed by unilateral RE (4 × 7 maximal repetitions) for both arms. Thus, one arm performed AE+RE interspersed with 15 min recovery, whereas the other arm conducted RE alone. Muscle biopsies were taken from the triceps brachii of each arm immediately before (PRE) and 15 min (POST1) and 3 h (POST2) after RE. Molecular markers involved in translation initiation, protein breakdown, mechanosignaling, and ribosome biogenesis were analyzed. Peak power during RE was reduced by 24% (±19%) when preceded by AE (P < 0.05). Increases in PGC1a and MuRF1 expression were greater from PRE to POST2 in AE+RE compared with RE (18-vs. 3.5- and 4- vs. 2-fold, respectively, interaction, P < 0.05). Myostatin mRNA decreased in both arms (P < 0.05). Phosphorylation of AMPK (Thr172) increased (2.5-fold), and 4E-BP1 (Thr37/46) decreased (2.0-fold), after AE (interactions, P < 0.05). p70 S6K, yesassociated protein, and c-Jun NH2-terminal kinase phosphorylation were unaltered, whereas focal adhesion kinase decreased ~1.5-fold, and β1- integrin increased ~1.3- to 1.5-fold, (time effect, P < 0.05). Abundance of 45S pre-ribosomal (r)RNA (internally transcribed spacer, ITS) decreased (~30%) after AE (interaction, P < 0.05), whereas CMYC mRNA was greater in AE+RE compared with RE (12-fold, P < 0.05). POLR1B abundance increased after both AE+RE and RE. All together, our results suggest that a single bout of AE leads to an immediate decrease in signaling for translation initiation and ribosome biogenesis. Yet, this did not translate into altered RE-induced signaling during the 3-h postexercise recovery period. [ABSTRACT FROM AUTHOR]

Introduction. The purpose of the study was to quantify the impact of packaging type, storage temperature, and length of postmortem aging to consistently increase palatability and color stability of Longissimus lumborum (LL) and TBmuscles that represent the bulk of today’s supply. Materials and methods. Paired longissimus lumborum (LL) and triceps brachii (TB) muscles were selected from 27 and 54 A-maturity beef carcasses with marbling scores of Slight 50 to Small 50 at grading. One muscle from each pair was stored at 0 and 4 °C, respectively, for 21, 32, or 42 days for LL, and 21, 28, or 35 days for TB, in one of three packaging options; DryBag®, traditional vacuum-bag, or no bag. Result and discussion. Saleable yields were similar forDryBag®and traditional dry agedsubprimals. Aging temperature and packaging type had little impact on any quality parameters evaluated. Steaks from LL muscles aged for 42 days had lower shear force values and more tender trained sensory panel values than steaks from LL aged for 21 days, although the actual difference was marginal. Tenderness of steaks from TB muscles was similar regardless of aging. Length of aging had more influence on saleable yields than palatability, and storage temperature and packaging had little influence on either. Conclusion. Traits measured from subprimals aged in a DryBag® were similar to traditional dry aging. Packaging (vacuum vs. non) had a slight influence on palatability. Storage temperature (0 vs. 4 °C) had little impact on any trait evaluated. Length of aging (21 to 42) had more influence on cutting yields than palatability. [ABSTRACT FROM AUTHOR]

Background: Free throws are a very important element in modern basketball. There are many studies focused on different aspects ranging from variability in the mechanics of throwing at various skill levels to the influence of free throws on the results of games. Objective: Since the authors of the present study noticed that some players during a game apply static stretching of shooting arm as a preparation to perform the free throw, we wanted to question the justification of such procedure prior to the performance of free throws. The purpose of this study was to determine an effect of submaximal 15 seconds static stretching of the upper arm (m. triceps brachii) and forearm (m. flexor carpi radialis) on the accuracy of free throws in basketball. Methods: Participants of the present study were 100 basketball players; mean age was 18.2 ± 2.54 years. The sample was divided into two groups - players with higher (n = 70; 6.83 ± 1.83 hours/week) and lower number (n = 30; 4.17 ± 0.48 hours/week) of training sessions per week. Furthermore, we compared separately experienced (n = 47; 12.2 ± 0.55 years) and less experienced basketball players (n = 53; 6.4 ± 0.45 years). The procedure purported that every player performs five free throws without prior stretching, five free throws immediately after 15 seconds of static stretching of upper arm muscle (m. triceps brachii), and five free throws after 15 seconds of static stretching of the forearm (m. flexor carpi radialis). Results: Fifteen seconds of static stretching of the upper arm and forearm muscles had a negative influence on the accuracy of free throw shooting in basketball. Players with a higher number of training sessions per week showed better tolerance to this negative influence. Conclusion: Results of this study indicate that is not useful to apply static stretching of the triceps brachii and flexor carpi radialis muscles just before the execution of free throws.

Highlights • Corticospinal excitability to biceps brachii is phase-dependent during arm cycling. • Corticospinal excitability to biceps brachii is task-dependent during arm cycling. • Corticospinal excitability to the biceps and triceps brachii are different. Abstract The purpose of the present study was to examine corticospinal excitability to the biceps and triceps brachii during arm cycling and an intensity-matched tonic contraction using stimulus response curves (SRCs) elicited via transcranial magnetic stimulation (TMS). Corticospinal excitability was assessed using TMS elicited motor-evoked potentials (MEPs) at eight different stimulation intensities (85–190% of MEP threshold). MEPs were recorded during arm cycling at two different positions, mid-elbow flexion (6 o'clock relative to a clock face) and mid-elbow extension (12 o'clock relative to a clock face), in addition to an intensity-matched (12 o'clock) tonic contraction. At the 12 o'clock position, the slope of the SRC was significantly lower during arm cycling than the tonic contraction for the biceps brachii (Cycling: 0.64 ± 0.47, Tonic: 1.02 ± 0.38, P < 0.05) but was not different for the triceps brachii (Cycling: 1.33 ± 0.49, Tonic: 1.48 ± 0.43, P = 0.42). Within arm cycling, the SRC slope was significantly greater at the 6 o'clock position than 12 o'clock position for the biceps brachii (6 o'clock: 1.37 ± 0.24, 12 o'clock: 0.64 ± 0.47, P < 0.05) but was not different for the triceps brachii (6 o'clock: 1.11 ± 0.28, 12 o'clock: 1.33 ± 0.49, P = 0.34). These findings demonstrate that corticospinal excitability to the biceps brachii is task-dependent during the extension phase of arm cycling. Neither position nor task influenced corticospinal excitability to the triceps brachii, providing further support that the motor control of locomotor outputs is muscle-specific. [ABSTRACT FROM AUTHOR]

Purpose: The main objective of the study was to examine the use of teres major (TM) as a flap in the pediatric surgeries from an anatomical perspective by: (1) revealing the growth dynamics of the developing TM; (2) assessing the possible interconnecting structures between TM and latissimus dorsi (LD); (3) exposing the innervation patterns of TM in human fetuses.Methods: Study was conducted on 50 fetuses (26 females and 24 males), on a mean gestational age of 22.86 ± 3.21 (range 18-30) weeks. All the measurements were collected with a digital caliper and a digital image analysis software. Additionally, structural relations between TM and LD were examined in detail and further classified.Results: No significant difference of side and sex was detected on TM measurements (p > 0.05). Linear functions for the surface area, width, length of the superior and inferior margins of TM were detected as follows: y = − 257.142 + 18.334 × age (weeks), y = − 5.497 + 0.545 × age (weeks), y = − 1.621 + 1.068 × age (weeks), and y = − 2.147 + 1.284 × age (weeks), respectively. As classified in five types, a number of 33 muscular or tendinous connections between TM and LD were detected. Musculo-tendinous slips from TM to triceps brachii (TB) were evident in four sides. Innervation of TM was observed to be providing by the lower subscapular nerve in all the cases.Conclusion: First, linear functions, representing the developing fetal morphometry obtained by our study can be adapted for estimating the morphometric of this muscle in early childhood. Besides, acknowledging the diverse appointments of TM with the surrounding muscles such as LD and TB may facilitate the prevention of neurovascular structures and the application of surgical procedures during tendon transfers. In brief, our findings are highly potent to bring the attention of pediatric surgeons. [ABSTRACT FROM AUTHOR]

A total number of fifty forelimbs comprising Twenty-five forelimbs male dromedary camels (camelus dromedaries) and those of male cattle, Zebu type, (Bos taurus indicus) within the ages of 6 months, 1 year, 3 years, 5 years and 7 years, were purchased from Sokoto Municipal Modern abattoir. Selected muscles sampled (1 cm2) from the forelimbs of both cattle and camel were taken from the middle part of the muscle bellies (from the biceps brachii, triceps brachii and deltoideus), fixed in Bouin's solution and prepared for histochemical analyses. The photomicrographs obtained from the biceps brachii, deltoideus and triceps brachii among both cattle and camel demonstrated the morphology of the different fibre types (type I, type IIA and type IIB). Muscle fibre types showed different proportions. Even though the overall mean proportion of muscle fibre type I, type IIA and type IIB could not present any significant (p>0.05) differences between the camel and the cattle looking at it holistically. As revealed in this work, the effects of the interactions of species versus age, species versus muscle and muscle versus age on the proportion of muscle fibre type I revealed that the deltoideus muscle of 1 year old camel had significantly (p<0.05) higher proportion. Type IIA muscle fibre obtained from the deltoideus muscle of 5-year-old camel showed a significantly highest value, while muscle fibre type IIB showed significantly higher value from the triceps brachii of cattle aged 1 year. The importance of the knowledge of microscopic characteristics in the determination of myofibre types could be of help in advancing the knowledge on muscle morphology (anatomy) and as well be of help in meat science industry. [ABSTRACT FROM AUTHOR]

Transcranial magnetic (TMS) and motor point stimulation have been used to determine voluntary activation (VA). However, very few studies have directly compared the two stimulation techniques for assessing VA of the elbow flexors. The purpose of this study was to compare TMS and motor point stimulation for assessing VA in non-fatigued and fatigued elbow flexors. Participants performed a fatigue protocol that included twelve, 15 s isometric elbow flexor contractions. Participants completed a set of isometric elbow flexion contractions at 100, 75, 50, and 25% of maximum voluntary contraction (MVC) prior to and following fatigue contractions 3, 6, 9, and 12 and 5 and 10 min post-fatigue. Force and EMG of the bicep and triceps brachii were measured for each contraction. Force responses to TMS and motor point stimulation and EMG responses to TMS (motor evoked potentials, MEPs) and Erb's point stimulation (maximal M-waves, Mmax) were also recorded. VA was estimated using the equation: VA% = (1−SITforce/PTforce) × 100. The resting twitch was measured directly for motor point stimulation and estimated for both motor point stimulation and TMS by extrapolation of the linear regression between the superimposed twitch force and voluntary force. MVC force, potentiated twitch force and VA significantly (p < 0.05) decreased throughout the elbow flexor fatigue protocol and partially recovered 10 min post fatigue. VA was significantly (p < 0.05) underestimated when using TMS compared to motor point stimulation in non-fatigued and fatigued elbow flexors. Motor point stimulation compared to TMS superimposed twitch forces were significantly (p < 0.05) higher at 50% MVC but similar at 75 and 100% MVC. The linear relationship between TMS superimposed twitch force and voluntary force significantly (p < 0.05) decreased with fatigue. There was no change in triceps/biceps electromyography, biceps/triceps MEP amplitudes, or bicep MEP amplitudes throughout the fatigue protocol at 100% MVC. In conclusion, motor point stimulation as opposed to TMS led to a higher estimation of VA in non-fatigued and fatigued elbow flexors. The decreased linear relationship between TMS superimposed twitch force and voluntary force led to an underestimation of the estimated resting twitch force and thus, a reduced VA.

Our objectives were to assess quality parameters and chemical composition, and to evaluate the effects of sex, muscle and aging time on the quality of meats from Wagyu · Angus cross cattle reared under tropical conditions· Analyses were performed on the longissimus thoracis, semitendinosus and triceps brachii muscles obtained from chilled carcasses of a total of 30, 24-month-old, male (immunocastrated) and female animals (15 each sex)· An effect of sex (P ≤0·05) was observed for subcutaneous fat thickness, marbling score, and ribeye area· The longissimus thoracis muscle from males was less (P < 0·0001) marbled than that from females, but males had greater subcutaneous fat thickness (P = 0·0001) and greater ribeye area (P = 0·0411) compared with females· No effect of sex (P ≥ 0·05) was observed for fat colour measures· An interaction effect of sex and muscle (P < 0·03) was detected for cooking loss, yellow intensity (b*), ash, and fat· Main effect of sex was not observed (P > 0·07) only for the ultimate pH and water-holding capacity· Greater shear force and moisture values were observed (P < 0·01) in meat from males than that from females, but a greater value of luminance (L*), red intensity (a*), chroma (C), hue (Ho), dry matter and protein was observed (P < 0·001) in meat from females than that from males· Main effect of muscle was not observed only for water-holding capacity (P = 0·13)· Ultimate pH and shear force values were lesser (P < 0·001) in the longissimus thoracis muscle compared with other muscles· The triceps brachii muscle had the least (P ≤0·001) L* and Ho values among muscles, whereas the semitendinosus muscle had the greatest values of a* and C (P < 0·001)· The semitendinosus muscle presented the greatest (P < 0·01) protein content compared with other muscles, although not differing in moisture and dry matter content from the triceps brachii muscle· An interaction effect of seaging time was observed for ultimate pH (P = 0·0110), meat colour parameters (except for Ho; P ≤0·01), and fat L* (P = 0·0025)· Greater cooking loss, shear force, and fat a* values were observed (P < 0·01) in meat from males than that from females, but greater values of meat Ho, fat a* and Ho, dry matter, and protein were observed (P ≤0·03) in meat from females than that from males· Meat aging of longissimus thoracis reduced shear force· Based on these findings, we recommend that meat from Wagyu · Angus cross cattle should be aged during 7 days because, although differences between 7 and 14 days were observed in either aging times, meat subjected to this process is considered as very tender, based on shear force values· In addition, aging in a shorter period of time can reflect on costs by reducing particularly those related with energy, due to less refrigeration time. [ABSTRACT FROM AUTHOR]

Objective The objective of this research was to summarize and analyse the research findings regarding analysis of fatigue in the human triceps brachii (TB) muscle through surface electromyography (sEMG) observations. Methods We systematically searched through five major online scientific databases namely the PubMed, Science Direct, Wiley Online, Springer Link and SCOPUS databases, for articles written in the English language from the year 2001 to March 2017. We specifically searched for the words/phrases “surface electromyography” OR “sEMG” AND “muscle fatigue” AND “triceps” in the title, abstract and keywords to narrow our search and identified 291 articles, of which, 52 were found potentially the most relevant. Results Of 52 considered articles, 11 analysed fatigue in sports, 11 investigated rehabilitation, 15 considered exercises or trainings, 5 used TB as a co-activator or antagonist, and 5 contemplated elbow extension movements. In addition, 4 of the articles investigated both elbow flexors and extensors and 1 studied training effects in rehabilitation. Conclusion Although, many studies in this particular field have considered the TB, further investigations are required to explain some specific facts about fatigue in the TB. The compensation strategy that muscles use to overcome fatigue, the stabilization, overcoming of errors during fatigue along with effect of mental load on brachii muscles and the effect of sports drinks and other eatables on fatigue are a few potential zones that require further in-depth research. This study will guide and direct new researchers to areas that remain hidden. [ABSTRACT FROM AUTHOR]

Introduction: This study examines effects of low-threshold afferents from the brachioradialis (BR) on excitability of triceps brachii (TB) motor neurons in humans.Methods: We evaluated the effects using a post stimulus time histogram (PSTH) and electromyogram averaging (EMG-A) methods in 13 healthy human participants. Electrical conditioning stimulation to the radial nerve branch innervating BR with the intensity below the motor threshold was delivered.Results: In the PSTH study, the stimulation produced a trough (inhibition) in 36/69 TB motor units for all the participants. A cutaneous stimulation never provoked such inhibition. The central latency of the inhibition was 1.5 ± 0.5 ms longer than that of the homonymous facilitation. In the EMG-A study, the stimulation produced inhibition in EMG-A of TB in all participants. The inhibition diminished with a tonic vibration stimulation to BR.Discussion: These findings suggest that oligosynaptic inhibition mediated by group Ia afferents from BR to TB exists in humans. Muscle Nerve 57: 122-128, 2018. [ABSTRACT FROM AUTHOR]