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International Journal of Environmental... Oct 2020The bench press exercise is one of the most used for training and for evaluating upper-body strength. The aim of the current study was to evaluate the electromyographic...
The bench press exercise is one of the most used for training and for evaluating upper-body strength. The aim of the current study was to evaluate the electromyographic (EMG) activity levels of the pectoralis major (PM) in its three portions (upper portion, PMUP, middle portion, PMMP, and lower portion, PMLP), the anterior deltoid (AD), and the triceps brachii (TB) medial head during the bench press exercise at five bench angles (0°, 15°, 30°, 45°, and 60°). Thirty trained adults participated in the study. The EMG activity of the muscles was recorded at the aforementioned inclinations at 60% of one-repetition maximum (1RM). The results showed that the maximal EMG activity for PMUP occurred at a bench inclination of 30°. PMMP and PMLP showed higher EMG activity at a 0° bench inclination. AD had the highest EMG activity at 60°. TB showed similar EMG activities at all bench inclinations. In conclusion, the horizontal bench press produces similar electromyographic activities for the pectoralis major and the anterior deltoid. An inclination of 30° produces greater activation of the upper portion of the pectoralis major. Inclinations greater than 45° produce significantly higher activation of the anterior deltoid and decrease the muscular performance of the pectoralis major.
Topics: Adult; Arm; Electromyography; Humans; Muscle Strength; Muscle, Skeletal; Pectoralis Muscles; Weight Lifting
PubMed: 33049982
DOI: 10.3390/ijerph17197339 -
BMC Musculoskeletal Disorders Jun 2020The Glenohumeral internal-rotation deficit (GIRD) is related to the altered eccentric external-rotator (ER), the concentric internal-rotator (IR), muscle strength, and...
BACKGROUND
The Glenohumeral internal-rotation deficit (GIRD) is related to the altered eccentric external-rotator (ER), the concentric internal-rotator (IR), muscle strength, and the ER: IR ratio. GIRD has been documented as a risk factor for shoulder injuries. However, few studies have investigated the effect of an exercise training on these parameters in athletes with GIRD. Therefore, the purpose of this study was to evaluate the effects of an 8-week throwing exercise with a TheraBand for retraining the rotator cuff on Electromyography (EMG) activity of selected muscles, rotator cuff muscle strength, the glenohumeral (GH) joint IR range of motion (ROM) and GH joint position sense in asymptomatic male volleyball players with GIRD.
METHODS
Sixty male volleyball players with GIRD were randomized into either a training group or a control group. The experimental group underwent an 8-week throwing exercise with a TheraBand including 5 sessions of stretching and 3 sessions of strengthening exercises per week. The control group received an active self-exercise program. EMG (onset time and muscle activation), shoulder range of motion (ROMs), strength and GH joint position sense were all assessed pre and post trainings.
RESULTS
There were statistically significant within-group differences in the EMG activity of the anterior deltoid (p = 0.005), middle deltoid (p = 0.007), posterior deltoid (p = 0.004), infraspinatus (p = 0.001) and supraspinatus (p = 0.001) muscles, IR ROM (p = 0.001), rotator cuff muscle strength ratio (p = 0.001), and GH joint position sense (p = 0.033) in the experimental group. A 2 × 2 analysis of variance with a mixed model design and independent and paired t-tests were used for statistical analysis.
CONCLUSIONS
Throwing exercise with a TheraBand improved shoulder muscle activation, IR ROM, rotator cuff muscle strength ratio and GH joint position sense in participants with GIRD. These findings may improve the treatment of GIRD in a clinical setting. Although the results are significant, further studies should follow up the long-term effects of the Throwing exercise with a TheraBand on GIRD.
TRIAL REGISTRATION
Current Controlled Trials using the UMIN-RCT website with ID number of, UMIN000038416 "Retrospectively registered" at 2019/10/29.
Topics: Adult; Biomechanical Phenomena; Electromyography; Exercise Therapy; Humans; Male; Muscle Strength; Range of Motion, Articular; Risk Factors; Rotation; Rotator Cuff; Shoulder Impingement Syndrome; Shoulder Joint; Volleyball; Young Adult
PubMed: 32534582
DOI: 10.1186/s12891-020-03414-y -
International Journal of Environmental... Aug 2020The present study examined the muscle activation in lateral raise with humerus rotated externally (LR-external), neutrally (LR-neutral), internally (LR-internal), with...
The present study examined the muscle activation in lateral raise with humerus rotated externally (LR-external), neutrally (LR-neutral), internally (LR-internal), with flexed elbow (LR-flexed) and frontal raise during both the concentric and eccentric phase. Ten competitive bodybuilders performed the exercises. Normalized surface electromyographic root mean square (sEMG RMS) was obtained from , , and , , , and . During the concentric phase, and showed greater sEMG RMS in frontal raise (effect size (ES)-range: 1.78/9.25)) and LR-internal (ES-range: 10.79/21.34), respectively, vs. all other exercises. showed greater sEMG RMS in LR-neutral than LR-external (ES: 1.47 (95% confidence-interval-CI: 0.43/2.38)), frontal raise (ES: 10.28(95% CI: 6.67/13.01)), and LR-flexed (ES: 6.41(95% CI: 4.04/8.23)). showed greater sEMG RMS in frontal raise vs. all other exercises (ES-range: 17.2/29.5), while (ES-range: 2.66/7.18) and (ES-range: 0.41/3.31) showed greater sEMG RMS in LR-internal vs. all other exercises. Similar recruitment patterns were found during the eccentric phase. When humerus rotates internally, greater activation of , , and occurs. Humerus external rotation increases the activation of and Frontal raise mainly activates and . LR variations and frontal raise activate specifically shoulders muscles and should be proposed accordingly.
Topics: Arm; Electromyography; Exercise; Humans; Muscle, Skeletal; Range of Motion, Articular; Shoulder; Weight Lifting
PubMed: 32824894
DOI: 10.3390/ijerph17176015 -
Journal of Sports Science & Medicine Jun 2020Push-ups are an ubiquitous resistance training exercise. While exhibiting a relatively similar upper body motion to the bench press, there are substantial differences in...
Push-ups are an ubiquitous resistance training exercise. While exhibiting a relatively similar upper body motion to the bench press, there are substantial differences in repetitions when employing similar relative loads. The objective was to examine sex-related differences in repetitions and muscle activation associated with push-ups and bench press exercises. Twenty resistance-trained participants (10 men [22 ± 6.1 years] and 10 [24 ± 5.7 years] women) performed maximum push-up and bench press repetitions with loads relative to the body mass during a push-up. Electromyographic (EMG) electrodes were positioned on the middle and anterior deltoids, triceps and biceps brachii, and pectoralis major muscles and their relative (normalized to a maximum voluntary contraction) activity was compared between the two exercises performed to task failure. Both females (3.5 ± 3.9 vs.15.5 ± 8.0 repetitions; p = 0.0008) and males (12.0 ± 6.3 vs. 25.6 ± 5.2 repetitions; p < 0.0001) performed 77.4% and 53.1% less bench press than push-up repetitions respectively. Males significantly exceeded females with both push-ups (p = 0.01) and bench press (p = 0.004) repetitions. Significant linear regression equations were found for females (r = 0.55; p = 0.03), and males (r = 0.66; p < 0.0001) indicating that bench press repetitions increased 0.36 and 0.97 for each push-up repetition for females and males respectively. Triceps (p = 0.002) and biceps brachii (p = 0.03) EMG mean amplitude was significantly lower during the push-up concentric phase, while the anterior deltoid (p = 0.03) exhibited less activity during the bench press eccentric phase. The sex disparity in repetitions during these exercises indicates that a push-up provides a greater challenge for women than men and regression equations may be helpful for both sexes when formulating training programs.
Topics: Adult; Electromyography; Female; Humans; Male; Muscle, Skeletal; Regression Analysis; Resistance Training; Sex Characteristics; Sex Factors; Young Adult
PubMed: 32390722
DOI: No ID Found -
PloS One 2023Rotator cuff tendinopathy is a common shoulder disorder in which the primary treatment is resistance exercises. Isometric exercises are being studied for lower limb...
Isometric versus isotonic exercise in individuals with rotator cuff tendinopathy-Effects on shoulder pain, functioning, muscle strength, and electromyographic activity: A protocol for randomized clinical trial.
INTRODUCTION
Rotator cuff tendinopathy is a common shoulder disorder in which the primary treatment is resistance exercises. Isometric exercises are being studied for lower limb tendinopathies but not for rotator cuff tendinopathy. This protocol for a randomized clinical trial aims to compare the effects of two types of exercise (isometric and isotonic) on shoulder pain, functioning, muscle strength, and electromyographic activity in individuals with rotator cuff tendinopathy.
METHODS
Forty-six individuals (18 to 60 years old) with shoulder pain for more than three months and unilateral supraspinatus and/or infraspinatus tendinopathy will participate in this trial. Individuals will be randomized into two exercise groups: isometric or isotonic. The following outcomes will be evaluated before and after the first session and after six weeks of intervention: shoulder pain and functioning; isometric strength of shoulder elevation and lateral and medial rotation; and electromyographic activity of medial deltoid, infraspinatus, serratus anterior, and lower trapezius. Groups will perform stretching and strengthening of periscapular muscles. The isometric group will perform three sets of 32 s, at 70% of maximal isometric strength. The isotonic group will perform concentric and eccentric exercises (2 s for each phase) in three sets of eight repetitions at a load of eight repetition maximum. The total time under tension of 96 s will be equal for both groups, and load will be adjusted in weeks three and five of the protocol. Treatment effect between groups will be analyzed using linear mixed model.
TRIAL REGISTRATION
Trial registration number: Universal Trial Number (UTN) code U1111-1284-7528 and Brazilian Clinical Trials Registry platform-RBR-3pvdvfk.
Topics: Humans; Adolescent; Young Adult; Adult; Middle Aged; Rotator Cuff; Shoulder Pain; Shoulder; Exercise Therapy; Tendinopathy; Muscle Strength; Randomized Controlled Trials as Topic
PubMed: 37956135
DOI: 10.1371/journal.pone.0293457