Abdominal and hip flexor muscle activation during various training exercises

Introduction: Overhead tasks increase the risk of work related musculoskeletal disorders to industrial workers. A shoulder supporting exoskeleton with adjustable and angle dependent torque (referred to as shoulderX in this paper for brevity) was designed and built at the University of California Berkeley Human Engineering and Robotics Laboratory for workers performing overhead tasks. shoulderX was designed specifically to reduce the exposure to large muscle exertion forces on the shoulder complex from overhead work. Methods: We evaluated shoulderX by measuring the muscle activation of the upper trapezius (UT), anterior deltoid (AD), triceps long head (TR), and infraspinatus (IF) during static and dynamic overhead tasks. Thirteen male subjects with experience in the construction or manufacturing industries were recruited to perform overhead tasks using light (.45 kg) and heavy (2.25 kg) weight tools with four exoskeleton support levels (0, 8.5, 13.0, 20.0 Nm peak torque). Results: During all conditions, the wearer’s shoulder flexor muscle activity of UT, AD were reduced with increasing strength of shoulderX by up to 80%. Subjects unanimously preferred the use of shoulderX over the unassisted condition for all task types (static and dynamic overhead tasks) and tool weights (.45 kg and 2.25 kg). Conclusion: shoulderX reduces the wearer’s primary muscle activity in overhead static and dynamic work and results in a more desirable and balanced pattern of shoulder complex activation. This investigation indicates that shoulderX reduces the risk of work related shoulder injuries during overhead tasks.

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Hip flexor muscle size in ballet dancers compared to athletes, and relationship to hip pain

Physical Therapy in Sport ◽

10.1016/j.ptsp.2019.05.003 ◽

2019 ◽

Vol 38 ◽

pp. 146-151

Author(s):

Sophie Emery ◽

Jill Cook ◽

April-Rose Ferris ◽

Peter Smith ◽

Susan Mayes

Keyword(s):

Hip Pain ◽

Muscle Size ◽

Flexor Muscle ◽

Ballet Dancers ◽

Hip Flexor

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The Effects of Elbow Joint Angle Change on the Elbow Flexor Muscle Activation in Pulley with Weight Exercise

Journal of Physical Therapy Science ◽

10.1589/jpts.25.1133 ◽

2013 ◽

Vol 25 (9) ◽

pp. 1133-1136 ◽

Cited By ~ 5

Author(s):

Taewook Kang ◽

Youngjoon Seo ◽

Jaehoon Park ◽

Eunseok Dong ◽

Byungdo Seo ◽

...

Keyword(s):

Elbow Joint ◽

Muscle Activation ◽

Joint Angle ◽

Elbow Flexor ◽

Flexor Muscle ◽

Angle Change

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Comparison of Muscle Onset Activation Sequences between a Golf or Tennis Swing and Common Training Exercises Using Surface Electromyography: A Pilot Study

Journal of Sports Medicine ◽

10.1155/2016/3987486 ◽

2016 ◽

Vol 2016 ◽

pp. 1-9

Author(s):

John M. Vasudevan ◽

Andrew Logan ◽

Rebecca Shultz ◽

Jeffrey J. Koval ◽

Eugene Y. Roh ◽

...

Keyword(s):

Pilot Study ◽

Surface Electromyography ◽

Muscle Activation ◽

Turning Point ◽

Positive Association ◽

Spearman Correlation ◽

Healthy Male ◽

Training Exercises ◽

Male Subjects ◽

Activation Sequence

Aim. The purpose of this pilot study is to use surface electromyography to determine an individual athlete’s typical muscle onset activation sequence when performing a golf or tennis forward swing and to use the method to assess to what degree the sequence is reproduced with common conditioning exercises and a machine designed for this purpose.Methods. Data for 18 healthy male subjects were collected for 15 muscles of the trunk and lower extremities. Data were filtered and processed to determine the average onset of muscle activation for each motion. A Spearman correlation estimated congruence of activation order between the swing and each exercise. Correlations of each group were pooled with 95% confidence intervals using a random effects meta-analytic strategy.Results. The averaged sequences differed among each athlete tested, but pooled correlations demonstrated a positive association between each exercise and the participants’ natural muscle onset activation sequence.Conclusion. The selected training exercises and Turning Point™device all partially reproduced our athletes’ averaged muscle onset activation sequences for both sports. The results support consideration of a larger, adequately powered study using this method to quantify to what degree each of the selected exercises is appropriate for use in both golf and tennis.

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Hip flexor muscle strength but not size is reduced in patients with hip labral tears

Journal of Science and Medicine in Sport ◽

10.1016/j.jsams.2011.11.039 ◽

2011 ◽

Vol 14 ◽

pp. e19

Author(s):

D. Mendis ◽

S. Wilson ◽

D. Hayes ◽

M. Watts ◽

J. Hides

Keyword(s):

Muscle Strength ◽

Flexor Muscle ◽

Labral Tears ◽

Hip Flexor

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Effect of iliopsoas muscle tightness on electromyographic activity of hip extensor synergists during gait

Medical Journal of Tabriz University of Medical Sciences and Health Services ◽

10.34172/mj.2021.031 ◽

2021 ◽

Vol 43 (1) ◽

pp. 76-83

Author(s):

Shirin Aali ◽

Shahabeddin Bagheri

Keyword(s):

Stance Phase ◽

Muscle Length ◽

Gluteus Maximus ◽

Biceps Femoris ◽

Control Group ◽

Electromyographic Activity ◽

Flexor Muscle ◽

Adductor Magnus ◽

Muscle Tightness ◽

Hip Flexor

Background: Hip flexor muscles' tightness has been considered as one of the main risk factors for neuromuscular impairment of lower extremities not only lead to change the movement patterns but also probably result in changing the neuromuscular features of other muscles. The purpose of this research is study was to evaluate the iliopsoas tightness’ effect on electromyographic activity of hip extensor synergists during gait. Methods: In this case-control study fifteen 11-14 years old adolescents with iliopsoas tightness as experimental group, and 15 healthy adolescents which matched based on age, height, weight, body mass index, dominant leg and sport experience participated voluntarily as control group. Surface electromyographic activity of the gluteus maximus, adductor magnus and biceps femoris, were measured between groups during stance phase of gait. Results: Individuals with restricted hip flexor muscle length demonstrated more gluteus maximus activation during terminal stance (p=.001), more biceps femoris activation during mid stance (p=.002) and late stance (p=.001) and more adductor magnus activation during mid stance (p=.04) and late stance (p=.001). Conclusion: Adolescent soccer athletes with hip flexor muscle tightness exhibit more biceps femoris and adductor magnus and gluteus maximus activation during stance phase of gait. Thus, individuals with hip flexor muscle tightness appear to utilize different neuromuscular strategies to control lower extremity motion.

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Relationships between lower extremity strength and the multi-directional reach test in children aged 7 to 12 years

Hong Kong Physiotherapy Journal ◽

10.1142/s1013702519500136 ◽

2019 ◽

Vol 39 (02) ◽

pp. 143-150

Author(s):

Benjaporn Hirunyaphinun ◽

Soontharee Taweetanalarp ◽

Anong Tantisuwat

Keyword(s):

Lower Extremity ◽

Flexor Muscle ◽

Limits Of Stability ◽

Knee Flexor ◽

Lower Extremity Muscle ◽

Lower Extremity Strength ◽

Flexor Muscles ◽

Muscle Groups ◽

Control Balance ◽

Hip Flexor

Objective: This study investigates the relationships between the Multi-Directional Reach Test (MDRT) and lower extremity strength in typical children. Methods: The MDRT including forward, backward, leftward, and rightward directions was measured in 60 children aged between 7 and 12 years old with typical development. The lower extremity muscle groups were measured using a hand-held dynamometer. Results: The reaching score in each direction had positive relationships with the strengths of several lower extremity muscle groups ([Formula: see text] to [Formula: see text]). Only the strengths of the hip flexor and knee flexor muscles significantly correlated with the MDRT scores in all directions ([Formula: see text] to [Formula: see text]). Conclusion: This study highlights the strength of the hip and knee flexor muscle groups as being important domain to control balance in all directions. These findings may be used for therapists in planning a balance program to improve the limits of stability.

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