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Background and aim: Cryotherapy has long been introduced as a common method for preventing and reducing edema caused by traumatic injuries. Many studies have been conducted regarding other effects of cold such as its effects on muscle strength which provided controversial results over the past decades. The aim of this study is to investigate whether cold is capable of changing the muscle strength.

Materials and methods: The research was conducted on 30 volunteers with the mean age of 22 years. In a standard situation, the volunteers were asked to make their maximum grip force. Cold was applied over their anterior forearm using an ice pack for 15 minutes. The maximum grip force was measured before and within 1 to 120 minutes after cold application.

Results:The strength of the anterior forearm muscles decreased rapidly after cold application. The maximum reduction of muscle strength, in average 18% was observed after 10 minutes. This was followed by a gradual increase of grip force. After 120 minutes the force was increased to about 5% above the baseline force that was before cold application.

Conclusion: Regarding the slight increase in the muscle strength and its long delay, cryotherapy of muscles cannot be considered as a practical method in rehabilitation of patients. However, this method would be of great importance for athletes.

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Background and aim: The aim of this study was to verify the relationship between pelvic tilt and lumbar lordosis with muscle tightness, muscle strength, BMI, and age in standing position.

Material and methods: In this study, 75 healthy female subjects participated with age range 20-70 years, mean (SD) = 40.66 (13.69). Pelvic tilt and lumbar lordosis were measured in standing position with pelvic inclinometer and flexible ruler respectively. The length of muscles, including: erector spinae, iliopsoas, rectus femoris, hamstrings, tensor fascia lata & ilio tibial band, and gastrocnemius were assessed by Schober, Thomas, Ely, 90/90 SLR, Ober tests and passive dorsiflexion of foot, respectively. The strength of muscles, including: rectus abdominis, transversus abdominis, left & right obliqus, Gluteus maximums & medius, and quadriceps were evaluated by manual muscle tests.

 Results: The relationship between pelvic tilt and lumbar lordosis with muscle strength, BMI, and age was poor. Muscle tightness and muscle strength had no significant effect on pelvic tilt and lumbar lordosis.

Conclusion: The results of this study indicated that the evaluated variables including: pelvic tilt and lumbar lordosis, have poor correlation with muscle tightness, muscle strength, BMI, and age. 

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Background and aim: Assessment of hip strength needs a reliable method. Hand-held dynamometers are appropriate alternatives for manual muscle testing and isokinetics. Stabilizing the dynamometer with hand will increase error in measurements. The purpose of this study was to compare the test-retest reliability of hand-held dynamometer fixed by hand and fixed to a new stable frame for measuring hip extension, abduction and external rotation strength in healthy female athletes.
Materials and Methods: Normalized average and peak values of torque of three successive trials for each muscle group were calculated in two sessions one week apart in ten healthy female athletes. Strength was measured with hand-held dynamometer fixed by hand and fixed to the stable frame in each session. Intra-class correlation coefficients (ICC), coefficients of variation (CV) and standard error of measurement (SEM) were calculated to determine the reliability.
Results: For hip extension, abduction, and external rotation strength measured by hand fixation. The ICC ranged from -1.22 to 0.6, the CV ranged from 8% to 33% and the SEM ranged from 0.007 to 0.04. For strength measurements with stable frame, the ICC ranged from .93 to .96, and CV ranged from 5.26% to 7.94%. The range of the SEM was from .004 to .08.
Conclusion: Measurements of hip muscles strength with a dynamometer fixed to a stable frame showed higher reliability than fixation by hand in young female athletes. These findings support the error within hand fixation of dynamometers and the necessity for providing better fixation.

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Background and Aim: Patellofemoral pain syndrome (PFPS) is a common musculoskeletal condition. Women with patellofemoral pain syndrome would present significant weakness in many of hip muscle groups when compared with the healthy group. The objective of the present study was to compare the strength of hip abductor, extensor and external rotator muscle groups in sedentary women with bilateral patellofemoral pain syndrome to a matched control group of sedentary women without patellofemoral pain syndrome. 

Materials and Methods: Twelve women with bilateral patellofemoral pain syndrome as experimental group and other twelve matched women as control group participated in this study. Maximum isometric strength for three hip muscles including abductor, extensor and external rotator muscle groups was measured bilaterally in all subjects using a dynamometer fixed on a platform and finally averaged between two limbs and compared with the control group.

Results: The hip abductor, extensor and external rotator muscle groups of experimental group were statistically weaker than that of the control group (p< 0.001).

Conclusion:  It seems that lower limb muscles including hip muscles of women with patellofemoral pain syndrome become weaker due to disuse conditions. 

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Background and Aim: According to the further tendency of osteoporotic people to use the hip strategy to maintain stability, in present study, the relationship between hip, ankle and back extensor muscles strength and functional balance in healthy and osteoporotic postmenopausal women were evaluated.

  

Materials and Methods: Forty-five volunteer postmenopausal women were divided into two normal and osteoporosis groups according to their bone mineral density. Maximal isometric strength of hip, ankle, and back extensor muscles were assessed by a hand-held digital dynamometer. Functional balance was assessed by Near Tandem Stand (NTS), Star excursion (SE) and Figure of 8 walking (F8W) tests.

  

Results: In osteoporosis group, all muscle groups were significantly weaker than the normal group (P<0.05), and the time of F8W test was significantly more than normal group (P=0.031). Also, in osteoporosis group, hip adductors and extensors showed a significant correlation with three functional balance tests (P<0.05).

  

Conclusion: Regarding to decrease of muscle strength in osteoporotic women and its relationship to declining of functional balance in ADL, strengthening of hip and ankle muscle groups should be considered in their rehabilitation programs.

 

Keywords: Muscle strength, Functional balance, Postmenopausal women, Osteoporosis.