• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.343-347
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• 1994

The effects of low and high-voltage-electrical-stimulation and storing temperature on concentration of adenosine triphosphate (ATP) related compounds were studied in M. Semitendinosus muscles from Korean native cattle. Seven beef carcasses were split, the one side was electrically stimulated for 1 minute by using stimulator adjusted to 400 V/60 Hz as high voltage or to 110 V/60 Hz as low voltage while the other side served as an unstimulated control. Both side samples were incubated at $5^{\circ}C\;and\;15^{\circ}C$ for 3 days. During storage, the concentration of ATP and its breakdown products were measured as a function of time. Significant differences (p<0.05) were observed in the variance of ATP, adenosine diphosphate (ADP) and inosine monophosphate (IMP) levels between low-or high-voltage-electrically stimulated muscles and unstimulated control at just after post-stimulation. The decomposition of adenosine compounds and the production of inosine compounds of low-voltage-electrically stimulated muscles were advanced more slowly than those of high-voltage-treatment muscles. With increasing storage time, the influence of electrical stimulation on changes of ATP related compounds in meat was decreased, but storing temperature begin to affect their concentration. Significant difference in the Hypoxanthine levels (p<0.05) was found of sample stored for 48 hours at $15^{\circ}C$ from samples stored at $5^{\circ}C$ regardless of electrical stimulation treatemt. IMP and inosine values in electrically stimulated muscles, higher than of a control during 72 hours of storage, indicated rapid production of flavor compounds in beef.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.1
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• pp.125-129
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• 2011

The aim was to determine the relationship between muscle structure and meat quality traits in neuromuscular compartments (NMCs: R1, R2, R3, R4) of pig semitendinosus muscle. Barrows from the INTA-MGC genetic line (Argentina) were slaughtered at 100 kg body weight. In each NMC the following parameters were determined: the fibre types I, IIA, IIX and IIB by immunohistochemistry, the fibre cross sectional area (FCSA), the pH of meat after 24 h post-mortem ($pH_{24}$), instrumental meat tenderness (WB) and colour ($L^*$, $a^*$, $b^*$). There were significant differences in the following: $L^*$ (R1 = R4$a^*$ (R1>R4>R2 = R3), $b^*$ (R1 = R4R1 = R3 = R4), $pH_{24}$ (R1 = R4>R2 = R3). The relative percentages of FCSA were as follows: I (R4>R1>R3>R2), IIA (R1>R4>R3>R2), IIX (R1 = R2 = R3 = R4) and IIB (R2>R3>R1>R4). The correlation values were statistically significant between IIB and WB (R1 and R4, $r_s$ = 0.66), (R2 and R3 $r_s$ = 0.74), IIB and $L^*$ (R1 and R4 $r_s$ = 0.84), IIX and $L^*$ without discriminating NMCs. Our data suggest that the NMC where the sampling takes place is important for determining meat quality traits because of the heterogeneity of the whole muscle.

• Physical Therapy Korea
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• v.17 no.1
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• pp.17-25
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• 2010

The aim of this study was to investigate the effect of supporting surface instability to trunk and lower extremity muscle activities during bridging exercise combined with core-stabilization exercise. Thirty young healthy adults (15 males and 15 females) voluntarily participated in this study. Each subject was asked to perform bridging exercise combined with core-stabilization exercise on three different supporting surfaces (stable ground surface, the wooden balancing board, and the air cushion). The muscle activities were measured using surface electromyography (EMG) during performing exercise. To test statistical significance, one-way ANOVA with repeated measures was used with the significance level of .05. The findings of this study are summarized as follows. (1) There were significant differences in muscle activities on internal oblique, external oblique, gluteus medius, semitendinosus, biceps femoris, medial gastrocnemius and lateral gastrocnemius during exercise (p<.05). (2) The biceps femoris and lateral gastrocnemius showed significantly higher muscle activity on the wooden balancing board rather than on the ground, and semitendinosus, biceps femoris, medial gastrocnemius and lateral gastrocnemius showed significantly higher muscle activity on the air cushion rather than on the ground (p<.05). Therefore, it is concluded that muscle activities in the trunk and the lower limbs during bridging exercise combined with core-stabilization exercise was affected with instability of supporting surface. Further researches are needed to investigate the long term effect of bridging exercise on muscle activity with patient group.

• Korean Journal of Applied Biomechanics
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• v.15 no.1
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• pp.207-219
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• 2005

The purpose of this study was to determine the effect of the foot rotation on the lower limb muscles. Fourteen subjects performed step-up/step-down at a cadence of 80 beats/min, exercises with the foot neutral, $35^{\circ}$ internally rotated, and $35^{\circ}$ externally rotated, respectively. For each variable, a one-way analysis of variance (ANOVA) was used to determine whether there were significant differences between genders and among the eight types of jump. When a significant difference was found in jump type, post hoc analyses were performed using the Tukey procedure. A confidence level of p < .05 was used to determine statistical significance. The results showed that significant changes in averaged IEMG values occurred with the internal rotation of the foot in the lateral gastrocnemius during the knee extension, and in the semitendinosus during the knee flexion. During the knee extension, however, the internal rotation of the foot produced a significantly lower Averaged IEMG values than the neutral foot position in the medial gastrocnemius. The results also found that the peak IEMG activity of the rectus femoris during the knee extension for the external rotation of the foot was Significantly higher than the corresponding values in the neutral position of the foot, while the intenal rotaion of the foot exhibited a significant difference with the neutral position of the foot in the semitendinosus during the knee flexion. In general, the foot rotation position did not influence the average IEMG and Peak IEMG values of most muscles. The practice of adopting foot rotation to selectively strengthen individual muscles of the lower limb was not supported by this study. The external rotation of the foot produced high muscle activities in the quadriceps during the knee extension. For the knee extension, therefore, maintaining a laterally rotated position should be need for stable and comfortable position.

• Journal of the Korean Arthroscopy Society
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• v.9 no.2
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• pp.123-131
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• 2005

The central third of the patellar tendon and hamstring tendons(semitendinosus and gracilis) are the most frequently used tissues for intra-articular replacement of the anterior cruciate ligament(ACL). At present, many surgeons consider the central third patellar ten don graft to be the gold standard for replacement of the ACL. Recent prospective studies by Marder et at and Aglietti et al, however, have failed to show any statistically significant differences in knee stability and functional outcome between central third patellar tendon grafts and hamstring tendon grafts. The review of this article is to (1) review the historical use of hamstring tendon grafts for ACL reconstruction; (2) discuss indications for use of hamstring tendon grafts for ACL reconstruction; (3) describe our present operative technique using a combined double-looped semitendinosus and gracilis graft with $RIGIDFIX^{circledR}$ and $INTRAFIX^{circledR}$ and (4) review the results of hamstring ACL reconstructions.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.10
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• pp.1492-1497
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• 2005

The goal of the trial was to evaluate the effects of ractopamine (20 ppm in the ration) given pregnant sows during three different pregnancy stages (T1: 25 to 50 d; T2: 50 to 80 d; T3: 25 to 80 d of gestation, and T4: control-no ractopamine) on fetal muscle development (through counts of the number of fibers of the semitendinosus muscle), on the growth and carcass characteristics of the progeny. Forty eight weaned piglets (12 per treatment) were assessed for number of muscle fibers, while performance and carcass characteristics were evaluated on a separate 48 animals (12 per treatment) grown to 100 kg. Animals produced by sows treated from 25 to 50 d of pregnancy (T1) resulted in non-significant increase of 6.85% in the number of muscle fibers in the semitendinosus muscle when compared to animals from the control group. Performance results were significantly different (p<0.05), and animals produced by sows from the T1 group gained more weight during the growth I stage (25 to 50 kg) and during the total period (6 to 100 kg) (991 vs. 903 grams, and 844 vs. 772 grams, respectively) when compared to controls. For carcass characteristics, results showed that animals produced by the T1 group of sows were heavier at slaughter (p<0.05) when compared to the controls (T4) (100.17 vs. 93.09 kg). There was a positive correlation between number of muscle fibers and bodyweights, carcass weights, Longissimus dorsi muscle depth and dressing out (0.80, 0.86, 0.67, and 0.50, respectively). Sows treated with ractopamine between 25 to 50 d of pregnancy produced piglets that performed better and had superior carcass characteristics than those produced by untreated sows. The ractopamine used for pregnancy sows (25 to 50 d) can be indicated as a device to increase the progeny performance.

• Physical Therapy Korea
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• v.9 no.3
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• pp.23-37
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• 2002

This study examined the muscle recruitment order during extension of the hip joint in normal subjects, and evaluated whether the external support obtained from wearing a lumbosacral corset had an effect on muscle recruitment leading to increased lumbar stability. The subjects were 40 normal adults (32 male, 8 female) with no history of low back pain and no pathological findings in the nervous or musculoskeletal systems. All subjects extended their hip joints under 3 positions (prone, sidelying, standing). During extension, the onsets of contraction of the rectus abdominis, gluteus maximus, and semitendinosus muscles were measured. Electromyographic activity was measured using a surface electrode, and the muscle contraction onset time was designated as the point exceeding a threshold of 25 ms, using a mean plus twice of the standard deviation. To compare the average order of muscle contraction onset time, a Freedman two-way analysis of variance by ranks was used. The relative difference between muscle contraction onset time wearing and not wearing a lumbosacral corset was measured using a paired t-test. A difference in the average muscle contraction onset order for the rectus abdominis, gluteus maximus, and semitendinosus muscles was observed (p<.05) among three positions. However, wearing a lumbosacral corset did not. change the contraction order. In addition, wearing a lumbosacral corset produced a significant difference (p<.05) in the relative onset time between the rectus abdominis and gluteus maximus in the standing position, but no difference was observed for the other muscles or positions. In the future, patients suffering from low back pain should be compared with normal subjects to determine the effectiveness of a lumbosacral corset in changing muscle recruitment order.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.9
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• pp.1364-1368
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• 2003

Effect of slaughter age (24, 28 and 38 months of age) on beef color stability during display of m. serratus ventralis, m. psoas major, m. semitendinosus and m. longissimus thoracis from Japanese Black steers was studied. Steak samples from muscles were over-wrapped with PVC film and displayed under fluorescent lights at $4^{\circ}C$ for 12 days. Percentages of metmyoglobin of steak samples were determined at days 0, 3, 6, 9 and 12. The percentage of metmyoglobin of m. psoas major at day 3 of display in the 24 months group was lower (p<0.05) than that in the 38 months group. The percentage of metmyoglobin of m. semitendinosus at day 6 of display in the 38 months group was higher (p<0.05) than that in the other groups. The percentage of metmyoglobin of m. longissimus thoracis at day 3 of display in the 24 months group was lower (p<0.01) than that in the other groups. The percentage of metmyoglobin of m. longissimus thoracis at day 6 (p<0.01), 9 (p<0.01) and 12 (p<0.05) of display in the 38 months group were higher than those in the other groups. Crude fat concentration in m. longissimus thoracis increased (p<0.05) after 28 months of age. $\alpha$-Tocopherol concentration in m. serratus ventralis in the 38 months group was higher (p<0.001) than that in the other groups. In m. psoas major the $\alpha$-tocopherol concentration in the 38 months group was higher (p<0.05) than that in the 24 months group. The $\alpha$-tocopherol concentration in m. longissimus thoracis increased (p<0.001) with age. These results suggested that in spite of increase in both the crude fat and the $\alpha$-tocopherol concentrations in m. longissimus thoracis, the beef color stability during display became short with age.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.5
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• pp.723-731
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• 2013

This study provides a comparative analysis of the effects of pre-slaughter penetrative and non-penetrative stunning and post-slaughter stunning on meat quality attributes in longissimus lumborum (LL) and semitendinosus (ST) muscles in heifers. Ten animals were assigned to each of four treatment groups: i) animals were subjected to conventional Halal slaughter (a clean incision through the structures at the front of the upper neck - the trachea, oesophagus, carotid arteries and jugular veins) and post-cut penetrating mechanical stun within 10 to 20 s of the neck cut (Unstunned; US); ii) high power non-penetrating mechanical stunning followed by the neck cut (HPNP); iii) low power non-penetrating mechanical stunning followed by the neck cut (LPNP); and iv) penetrative stunning using a captive bolt pistol followed by the neck cut (P). For each carcass, muscle samples were removed within 45 min of slaughter, portioned and analysed for pH, cooking loss, water holding capacity (WHC), tenderness (WBS), lipid oxidation (TBARS) and color, over a two week storage period. Stunning did not affect pH and cooking loss. Significant differences in water holding capacity, tenderness, lipid oxidation and color were present at different storage time points. HPNP stunning resulted in lower WHC and color values, particularly lightness ($L^*$), higher TBARS values and peak force values compared with those stunned using LPNP, P and US. These adverse effects on quality were mostly encountered in the ST muscle. In conclusion, the meat quality achieved using P, LPNP and US treatments was comparable, and no treatment stood out as considerably better than another.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.10
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• pp.1490-1495
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• 2013

Texture and 'tenderness' in particular, is an important sensory characteristic for consumers' satisfaction of beef. Objective and detailed sensory measurements of beef texture have been needed for the evaluation and management of beef quality. This study aimed to apply the sensory scales defined in ISO11036:1994 to evaluate the texture of beef. Longissimus and Semitendinosus muscles of three Holstein steers cooked to end-point temperatures of $60^{\circ}C$ and $72^{\circ}C$ were subjected to sensory analyses by a sensory panel with expertise regarding the ISO11036 scales. For the sensory analysis, standard scales of 'chewiness' (9-points) and 'hardness' (7-points) were presented to the sensory panel with reference materials defined in ISO11036. As a result, both 'chewiness' and 'hardness' assessed according to the ISO11036 scales increased by increasing the cooking end-point temperature, and were different between Longissimus and Semitendinosus muscles. The sensory results were in good agreement with instrumental texture measurements. However, both texture ratings in this study were in a narrower range than the full ISO scales. For beef texture, ISO11036 scales for 'chewiness' and 'hardness' are useful for basic studies, but some alterations are needed for practical evaluation of muscle foods.