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Background and Objective: The trigger point is the irritable point associated with a tight band of skeletal muscle which is painful against stress and strain. The real goal in treating trigger points is to achieve a degree of pain relief so that the sufferer can return to his usual activities and functions in spite of some pain. This study was carried out to compare of two methods of sports massage and cold stretch on the threshold of pain in passive trigger points in shoulder girdle muscles of the female volleyball players.
Methods: In this quasi-experimental study, 32 females national volleyball palyer who has a latent trigger point in the shoulder girdle region were non-randomly divided into to three groups of sports massage (n=11), stretching along the cold (n=11) and control (n=10) groups. Threshold of pain test was carried out in two steps, prior and immediately after sports massage and stretching along the cold.
Results: The mean of pain threshold prior and immediately after the study in control group was 38.84±11.348 and 35.16±9.311, respectively. The mean of pain threshold prior and immediately after the study in sports massage group was 39.40±9.88 and 43.54±9.63, respectively. This differernce was not significant. The mean of pain threshold prior and immediately after the study in stretching along the cold group was 39.22±10.57 and 41.10±10.95, respectively. This differernce was not significant.
Conclusion: Sports massage and stretching along the cold did not significant effect on the threshold of pain in passive trigger points in shoulder girdle muscles of the female volleyball players.

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Background and Objective: Life style with Low activity and overweight increased the risk of cardiovascular diseases. This study was done to evaluate the effect of ginger supplementation on Lactate dehydrogenase (LDH) changes and delayed muscle soreness following exhaustive eccentric exercise on overweight girls.
Methods: In this randomized clinical trial study, 22 overweight girls were randomly divided into the two groups including intervention (n=12) and control (n=10) groups. For subjects in interventional group were used a daily supplement of 2 grams of ginger powder, each serving a capsule, containing one gram of ginger powder  and subjects in control group were received  daily two capsules containing starch, for two weeks. Physical activity was performed consisting of two sessions of exhausting activity (negative tilt on treadmill, one session before supplementation and one session after two weeks of supplementation). Blood samples were measured in order to measure changes in LDH in four stages and the use of the pain questionnaire for evaluation of delayed muscular brittleness in both pre and post gingival supplementation. Pain scale (visual analogue scale: VAS) was used to measure the delay fatigue.
Results: The results showed that extrinsic exercise increased LDH and delayed muscle soreness after exercise (P<0.05). Also, taking two weeks of ginger supplementation significantly reduced LDH and delayed muscle soreness in the supplement group in comparison with controls (P<0.05).
Conclusion: Ginger can reduces the muscle gain and delayed onset muscle soreness resulting from eccentric exercise in overweight girls.

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Background and Objective: Creatine is one of the most important and commonly used supplements athletes, although the molecular mechanisms of creatine and its side effects are less understood. The high level of the ceratin kinase enzyme and lactate dehydrogenase enzymes are considered to be a sign of cell damage. This study was done to determine the effect of creatine monohydrate supplementation on creatine kinase (CK) and lactate dehydrogenase (LDH) enzymes following a severe muscle contraction in female athletes.
Methods: In this double-blind clinical trial study, 30 female athletes were randomly divided into intervention (creatine supplementation 0.3 grams per body weight for 4 times duing 7 days and control (placebo, starch powder) groups. Blood sample was collected before supplementation (pre-test) and 24 hours after Cunningham exercise test (post-test) to measuring CK and LDH in each subject.
Results: After intervention, the level of CK (323±63 IU/L) and LDH (119±13 IU/L) in intervention group had no significant difference in compared to control group (CK: 328±44 IU/L and LDH: 122±14 IU/L).
Conclusion: The usage of a 7-day course of creatine supplement did not significantly change the CK and LDH levels following a severe muscle contraction in female athletes.

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Background and Objective: Strength and flexibility are the factors affecting the athlete's performance. This study was done to determine the effect of eccentric training on knee strength and hamstring flexibility in active females with hamstring tightness.
Methods: In this clinical trial study, 24 active female athletes with hamstring tight were randomly divided into intervention and control groups. For measurement of strength, including the eccentric and concentric peak torque and the time to reach the peak torque in speeds of 60 and 180 degrees per second, isokinetic dynamometer device .For measurement of hamstring flexibility, a passive knee extension test was used six weeks before and after the eccentric training of hamstring.
Results: After six weeks of eccentric training, a significant  improvement was observed in test scores of passive knee extension (PKE) test and also in the maximum torque and time to reach the maximum torque eccentric flexor knee in angular velocity of 60 degrees per second in the interventional  group compared to controls (P<0.05).
Conclusion: Eccentric training increases flexibility and eccentric strength of hamstring muscles in active females with hamstring tightness.

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Background and Objective: Proprioceptors of the plantar surfaces of the foot have less efficiency and the stimulation and reinforcement of them may be lead to reduction of falling risk. One of the methods to reinforce proprioceptor receptors in these individuals is using textured foot orthoses. The aim of this study was to evaluate the effect of textured foot orthoses on frequency spectrum of lower extremity muscles, stance time and comfort in individuals over age of 55 years during walking.
Methods: This quasi-experimental study was done on the 14 females and 14 males age ranged of 56-70 years with the ability to walk independently and with physical and mental health status. Subjects were compared during five conditions including without foot orthoses and using four foot orthoses (including small and large foot orthoses with two types of flexible and rigid), flexible and rigid large textured foot orthoses. The 8 electrodes were located on tibialis anterior, medial gastrocnemius, vastus medialis, vastus lateralis, biceps femoris, semitendinisus, gluteus, and erector spinae in 3 lumbar vertebrae region muscles.
Results: Frequency content of tibialis anterior and vastus medialis was significantly increased in males than female (P<0.05). Vastus medialis frequency during walking with large foot orthoses was more than walking without foot orthoses (P<0.05). The comfort level was different during flexible large textured foot orthoses condition compared with flexible small textured foot orthoses condition (P<0.05). The stance time was not significant between all conditions.
Conclusion: Increased frequency content of the vastus medialis muscle can increase the absorption and decrease the vertical loading rate imposed on the foot, which in turn reduces the risk of injury of the lower limb in older adults.

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Background and Objective: Genu varus deformity is associated with changes of lower limb muscle co-contraction and running economy. This study was done to evaluate the effect of using of brace in three different knee flexion angles on running economy and lower limb muscular co-contraction in individuals with genu varus.
Methods: This quasi-experimental study was done on active soccer male students including 15 healthy subjects (average age of 22.86±1.55 years) and 15 subjects with genu varus (average age of 22.13±1.80 years). The amount of electrical activity of the muscles (tibialis anterior, medial gastrocnemius, vastus medialis, vastus lateralis, rectus femoris, biceps femoris, semi-tendinosus) were recorded by electromyography system during four conditions of with and without using knee brace. After that, directed and general co-contraction was computed during running. The angles of brace were 15, 30, and 60 degrees. The values of VO2 max were recorded using of gas analyzer system to compute running economy.
Results: The ratio of respiratory exchange was significantly more in the genu varus group than healthy group (P<0.05). However, the acute effect of brace was not significant on running economy and ratio of respiratory exchange. The main effect of brace was significant for general co-contraction of knee joint during the loading phase (P<0.05). Paired wise comparison revealed significant greater general knee co-contraction during brace conditions (P<0.05). However, the general knee co-contraction during loading phase reduced while using brace 15 degree. The main effect of “brace” for ankle joint general co-contraction during the push-off phase was significant (P<0.05). Paired wise comparison revealed significant greater general ankle co-contraction during brace conditions at push-off phase (P<0.05).
Conclusion: Knee brace did not change running economy. However, the using of brace 15 degree improved general knee joint co-contraction during loading phase.

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Background and Objective: Multiple sclerosis (MS) is one of the most common diseases of the central nervous system. MS is more common among women. Gait pattern dysfunction is a relevant symptom in these patients. This study was conducted to compare the electromyography activity of selected lower extremity muscles and the ellipse area of center of pressure during unplanned gait termination in female patients with multiple sclerosis and healthy individuals.
Methods: This case-control study was performed on 10 female patients with MS (classified based on the EDSS scale) and 10 healthy subjects matched for height, age and weight. Electromyography activity of rectus femoris (RF), vastus medialis (VM), vastus lateralis (VL), biceps femoris (BF), semitendinosus (SM), gastrocnemius medius (GM) and tibialis anterior (TA) and center of pressure (CoP) recorded using foot pressure system during unplanned gait termination. Subjects were instructed to stop, as soon as possible, in response to an auditory cue delivered when the heel strike phase accidentally.
Results: Vastus Lateralis muscle activity was significantly higher in able-bodied group than patients (P<0.05), whereas in the patient group gastrocnemius medius muscle activity increased significantly (P<0.05). Also, the ellipse area of center of pressure significantly reduced in MS group in compered to able-bodied group (P<0.05).
Conclusion: Increased gastrocnemius medius muscle activity in MS patients may be due to their attempt to slow down the displacement of the center of mass to limit the tibia forward translation consequently, attempting to control balance as a strategy to limit the ellipse area of center of pressure to prevent fall.

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Background and Objective: Genu valgum is one of the most common lower limb malformations that affects on walking mechanics. This study was done to evaluate the effect of corrective exercise with Thera-band on the lower limb muscles’ co-contraction in males with genu valgum during walking.
Methods: In this clinical trial study, 24 male students with genu valgus with age range of 20-30 years were randomly divided into two control (n=12) and intervention (n=12) groups. Using the caliper, the intensity of the genu valgum was measured by assessing the distance between the medial malleolus of the subjects. Corrective exercises were performed for 8 weeks using Thera-band in interventional group. The electrical activity of selected muscles was recorded by electromyography system (biometrics ltd, UK).
Results: In the interventional group, the knee joint flexor/extensor directed co-contraction was increased significantly during the heel contact phase in the post-test than that in the pre-test (P<0.05). There was also a significant increase in knee joint general co-contraction during heel off phase (P<0.05). In the interventional group, directed co-contraction of vastus lateralis / vastus medialis muscles during the swing phase was significantly increased during the post-test in compared to the pre-test (P<0.05). During post-test, knee joint flexor/extensor directed co-contraction during the heel, knee joint general
co-contraction during heel off phase and directed co-contraction of vastus lateralis / vastus medialis muscles during the swing phase were more in the interventional group in compared to control group (P<0.05).
Conclusion: The increase of general co-contraction in the knee joint during the heel off phase reflects an improvement in activity of the knee support muscles after corrective exercises and increases balance and stability. There was also an increase in the knee joint flexor / extensor direction co-contraction, which increase the distribution of the load and pressure between the femur and tibia in the knee joint.

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Background and Objective: Sphingosine-1-phosphate (S1P) plays an important role in muscle biology and is involved in hypertrophy and activation of satellite cells. This study was done to determine the effect of eight weeks of concurrent training with different order on S1P in fast and slow muscles in wistar rats.
Methods: In this experimental study, 40 male wistar rats (weight 180-200 gr) were randomly allocated into 5 groups including control, resistance training, endurance training, resistance- endurance training, endurance- resistance training. Resistance training consisted 1-meter ladder climbing with the loading of percent of overloading test (%75 of weight body) in the first week and increased to 30 gr per week. Endurance training consisted of running on treadmill with speed of 12 m/min and 10 minutes in the first week to 30 m/min and 60 minutes in the last week. The resistance- endurance group performed resistance training 5 minutes before endurance training and the endurance- resistance group performed endurance training 5 minutes after resistance training. The protein level of S1P was measured in flexor hallucis longus (FHL) and soleus muscles.
Results: The S1P level in fast and slow twitch muscle increased significantly in endurance- resistance training, resistance- endurance training and resistance training compared to controls (P<0.05). There were no significant differences between concurrent training with differing order.
Conclusion: It seems that exercise order in concurrent training result in no different effect on S1P level in fast and slow twitch muscles in wistar rats.

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Background and Objective: Genu varum is a lower limb deformity. This study was done to evaluate the effects of shoe aging on the general and directional contraction of ankle muscles during running in females with genu varum.
Methods: This case-control study was done on 30 female students (15 individuals with genu varum degree 2 and 15 healthy individuals) using new and old sneakers for 6 months in the sports biomechanics laboratory of the University of Mohaghegh Ardabili, Iran. Each subject was given a new pair of sneakers, and after the initial data collection, the subjects were asked to use them in their daily activities for at least an hour a day for 6 months. Electrical muscle activity was recorded using surface electromyography.
Results: There was no significant difference in the general and directional contractions if ankle muscles during the running phases.
Conclusion: Shoe aging has no effect on ankle joint co-contractions.
 

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Background and Objective: Neural, hormonal, and mechanical factors regulate the expression of fast-twitch isoforms in developing and mature muscle fibers. The transcriptional mechanisms responsible for regulating the gene expression of myosin heavy chain types are not well understood. This study aimed to determine the effect of a single session of intense resistance exercise with glutamine supplementation on the relative expression of the alpha and IIX isoforms of the myosin heavy chain gene in male rats.
Methods: This experimental study was conducted on 30 adult male Wistar rats divided into three groups: control, intense resistance exercise (first experimental group), and fierce resistance exercise combined with glutamine supplementation (second experimental group). The exercise groups participated in a single session of resistance climbing on an inclined plane with 4 sets of 5 repetitions, 30 seconds of rest between repetitions, and 2 minutes of rest between sets. Glutamine supplement powder was dissolved in 100 ml of distilled water at a dose of 0.5 grams per kilogram of body weight and administered daily via gavage for 5 days. The expression of alpha and IIX isoforms of the myosin heavy chain gene was examined in the extensor digitorum longus muscle tissue.
Results: The relative expression of the alpha myosin heavy chain gene in the fast-twitch muscle fibers increased significantly in the first experimental group (1.93±0.298) and the second experimental group (1.65±0.195) compared to the control group (P<0.05). The relative expression of the IIX motor unit gene in the fast-twitch muscle fibers also increased significantly in the first experimental group (1.42±0.239) and the second experimental group (1.26±0.190) compared to the control group (P<0.05). The increase in the relative expression of the alpha myosin heavy chain gene in the first experimental group compared to the second experimental group was statistically significant (P<0.05). However, the increase in the relative expression of the IIX motor unit gene in the first experimental group compared to the second experimental group was not statistically significant.
Conclusion: Our study concludes that a single session of intense resistance exercise, with or without glutamine supplementation, significantly increases the relative expression of the alpha myosin heavy chain gene and the IIX motor unit gene in the fast-twitch muscle fibers of the extensor digitorum longus muscle in adult male rats. These findings provide valuable insights into the molecular