Arm Flexion Research Articles

Modified Unipolar Latissimus Transfer to Restore Elbow Flexion in Musculocutaneous Nerve Palsy

Modified Unipolar Latissimus Transfer to Restore Elbow Flexion in Musculocutaneous Nerve Palsy

Outcomes of distal biceps tendon repair using a dual incision, cortical button technique: a single surgeon study.

BackgroundThe purpose of this study was to evaluate patient-reported outcomes, function, complication rates, and radiographs in a series of patients with distal biceps tendon repair using the dual incision cortical button technique by a single surgeon. By having a single surgeon perform the surgery, the technique is standardized to all patients. Twenty-two patients consented to participate in the study. The average time from surgery to review was 2.2 years. Patient satisfaction was assessed using the DASH, Oxford, and Mayo Elbow Performance Scores.MethodsRange of movement was assessed and compared to the unaffected limb using a goniometer. Isometric flexion and supination strength was tested using a standardized dynamometer—both measurements taken by a single physiotherapist. Radiographs were discussed at the time of the review by 2 orthopedic surgeons to check for heterotopic ossification.ResultsThe mean DASH score was 6.3 postsurgery at the time of follow-up. There was no significant difference in active range of movement between the repaired and nonrepaired arm in flexion, extension, supination, or pronation. Four radiographs showed evidence of heterotopic ossification (HTO)—none showed synostosis. For patients with HTO, there was evidence that supination was inhibited compared to those patients who did not have HTO.ConclusionOur study found that at an average of 2 years of follow-up these patients had good outcomes clinically with no major complications. HTO was present in only 4 patients, and there was a significant difference in supination compared to those who did not have HTO. These patients had an average DASH of 14 compared to a score of 4.5 in those who did not have an HTO. The study showed that the dual incision cortical button repair remains a procedure with excellent patient outcomes at the risk of HTO.

Which Risk Factors Are Associated with Pain and Patient-reported Function in Patients with a Rotator Cuff Tear?

Patient-reported measures guide physicians in clinical decision making and therefore it is critical to determine what clinical factors are associated with these scores. Psychological and physical factors are commonly studied separately in patients with rotator cuff tears to determine their influence on outcomes. It is well established that psychological distress and scapular motion change in the presence of a symptomatic rotator cuff tear. However, these factors have not been studied simultaneously in a clinical setting to determine their association with shoulder outcome scores. After controlling for relevant confounding variables, what physical and psychological factors are associated with better (1) American Shoulder and Elbow Surgeons (ASES) scores for function, (2) ASES pain scores, and (3) total ASES scores? Fifty-nine patients with a potential symptomatic rotator cuff tear were recruited and agreed to participate in this cross-sectional study. Of those, 85% (50 of 59) met eligibility criteria for a primary diagnosis of an MRI-confirmed symptomatic partial-thickness or full-thickness rotator cuff tear without a history of shoulder surgery. Demographics, rotator cuff tear size, arm flexion, and clinical scapular motion during active arm flexion were evaluated by experienced examiners using standardized procedures. Patients completed the ASES questionnaire and the Optimal Screening for Prediction of Referral and Outcomes-Yellow Flag assessment form, which measures 11 different pain-related psychological distress symptoms. Three separate stepwise multiple linear regression analyses were performed for ASES pain, function, and total scores, with significance set at p < 0.05. This model found that ASES function scores were associated with four factors: older age, increased arm flexion, increased percentage of scapular external rotation during arm flexion, and increased scores for acceptance of chronic pain (adjusted r2 = 0.67; p = 0.01). Those four factors appear to explain 67% of the observed variance in ASES function scores in patients with rotator cuff tears. Furthermore, increased percentage of scapular external rotation during arm flexion and decreased fear-avoidance beliefs related to physical activity scores (adjusted r2 = 0.36; p < 0.01) were associated with better ASES pain scores. And finally, better ASES total scores were associated with four factors: increased arm flexion, increased percentage of scapular upward rotation, increased scapular external rotation during arm flexion, and decreased fear-avoidance beliefs related to physical activity scores (adjusted r2 = 0.65; p < 0.001). Our results favor adopting a comprehensive biopsychological clinical assessment for patients with rotator cuff tears that specifically includes humeral and scapular motion, fear-avoidance behaviors, and pain coping behaviors along with demographics. These particular physical and psychological variables were found to be associated with the ASES and, therefore, should be clinically examined simultaneously and targeted as part of a tailored treatment plan. Level II, prognostic study.

The biomechanical role of the lacertus fibrosus of the biceps brachii Muscle

The lacertus fibrosus (LF) is involved in various surgeries. However, the biomechanical contribution of the LF remains unclear. The aim of this study was to determine the role of the lacertus fibrosus on the elbow and forearm kinematics and on the biceps brachii muscle lever arms. This biomechanical study was performed on seven fresh-frozen upper limbs of cadavers. Elbow flexion, forearm supination, and biceps brachii muscle lever arms were analyzed in the intact conditions (I) and after superficial (R) and deep part (R2) of the lacertus fibrosus release, respectively. Elbow flexion shows a significant difference (p < 0.0001) between I, R, R2. Abduction/adduction shows a significant difference between I-R (p < 0.0001) and I-R2 (p < 0.0001). Supination does not show a significant difference in mean maximum amplitude, but between 40 and 70%, there are significant differences. There is a significant mean decrease of lever arm in flexion (28%) and supination (50%) after superficial and deep part of the lacertus fibrosus release. The results of this study show that the lacertus fibrosus increases the lever arm during flexion and supination. It limits the flexion and abduction of the elbow and supination of the forearm. Lacertus fibrosus maintains the rhythmicity between the elbow flexion and supination of the forearm. Basic science study, biomechanics.

The Effect of the Change in Neck Position on Muscle Activity during Arm Flexion Exercise

The Effect of the Change in Neck Position on Muscle Activity during Arm Flexion Exercise

Associação de indicadores antropométricos com variáveis hemodinâmicas, glicemia e aptidão física de adultos

O estudo associou indicadores antropométricos com variáveis hemodinâmicas, glicemia e aptidão física de adultos. Participaram do estudo 60 adultos de ambos os sexos (32,90 ± 10,26), sedentários e iniciantes de uma academia de ginástica. Foram analisadas variáveis de pressão arterial, frequência cardíaca, glicemia, circunferência da cintura (CC), circunferência do quadril, relação cintura-quadril, relação cintura-estatura (RCE), índice de massa corporal, flexibilidade, e flexões de braço e abdominais. As variáveis antropométricas se correlacionaram positivamente com as hemodinâmicas e negativamente com os testes de aptidão física (p

Long-term Improvements of Neuroplasty and Scalene Muscle Resection in LTN-injured Winged Scapula Patients.

Background:Injuries to the long thoracic nerve, which directly branches off of the C6, C7, and C8 brachial plexus nerve roots, can cause scapular winging and affect shoulder movements. Long thoracic nerve injuries resulting from accidents, violence, or overuse can be severe lesions requiring challenging surgeries. We evaluated the long-term functional outcomes of neuroplasty and the scalene muscle resection procedures in patients with long thoracic nerve injury and winging scapula.Methods:All 15 patients who underwent scalene muscle resection with decompression and neurolysis of the long thoracic nerve in a single institution to treat winged scapula and limited shoulder movements between March 2007 and May 2020 with follow-up over 2 years were included in the study.Results:Shoulder abduction and arm flexion improved significantly to 158 ± 52 degrees and 165 ± 53 degrees from a mean of 108 ± 54 degrees and 104 ± 52 degrees (P < 0.02) over 2 years after surgery (mean 3.4 years). Overall, there was a significant reduction in the scapular winging, as assessed by estimating the decrease in the angle between the scapular plane and the posterior chest wall. The extent of the score greatly improved post-surgically from a mean of 1.2 ± 0.4 to 3.5 ± 0.9 (range 1–4; 1—severe, 2—moderate, 3—mild, and 4—minimal) (P < 0.01).Conclusion:The improvement in shoulder movements and reduced scapular winging was significant and stable over 2 years of surgery in 81% of our study patients.

Altering emotions near the hand: Approach-avoidance swipe interactions modulate the perceived valence of emotional pictures.

Approaching positive objects and avoiding negative ones are general action tendencies in human behavior. Interestingly, hand or arm positions connoting approach (arm flexion) or avoidance (arm extension) have also been shown to influence how the valence of a stimulus is evaluated. However, this causal effect on valence evaluation has been typically examined within experimental paradigms that do not require acting upon objects such as when touching or moving them. Accordingly, the current study attempts to integrate approach-avoidance paradigms with findings suggesting that manipulating visual stimuli directly by hand modulates their cognitive processing. Sixty participants evaluated the valence of 40 emotional pictures from the International Affective Picture System (IAPS) twice, first after watching them on a monitor (i.e., baseline evaluations) and second after swiping them on a touchscreen, either toward or away from their body (i.e., interactions regulating distance). Our findings confirmed that, in contrast to just watching the pictures, (a) swiping positive pictures closer and negative pictures away led to positively change their valence evaluation (i.e., reinforcing the perceived valence of positive pictures and attenuating the perceived valence of negative pictures). However, (b) swiping negative pictures closer and positive pictures away barely changed their initial valence evaluation. Against this background, we argue that swiping emotional pictures closer or away directly by hand, may intensify the attentional prioritization to interactions leading to more desirable consequences, namely, approaching positive and avoiding negative stimuli. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

The relationship between swimming performance and isokinetic shoulder strength of elite swimmers

PurposeThe aims of the study were to determine the relationship between the shoulder muscles strength and the athletic performance of high-level swimmers and to detect the strength variables that had the biggest impact on high performance in sports swimming.MethodsThe study involved 39 high qualified swimmers (12 females and 27 males). To determine the strength variables, shoulder flexion and extension were carried out in isokinetic conditions. A Biodex S4 dynamometer was used. The following protocols were applied: (1) 3 repetitions, 60°/s; (2) 20 repetitions, 180°/s. The r-Pearson correlation analysis or the rho-Spearman correlation analysis were used. The family-wise error was checked.ResultsThe level of strength had a greater influence on the swimming performance in males (25 of the 68 obtained variables) than in females (18 of the 68 variables). The strength variables that had the biggest impact on high performance in sports swimming were peak torque (&lt;i&gt;r&lt;/i&gt;: 0.39–0.633), total work (&lt;i&gt;r&lt;/i&gt;: 0.408–0.692), average power (&lt;i&gt;r&lt;/i&gt;: 0.44–0.739), and average peak torque (&lt;i&gt;r&lt;/i&gt;: 0.456–0.72).ConclusionsRegardless of the respondents’ gender or the analysed shoulder movement, the following variables were repeated: peak torque, total work, average power, and average peak torque. Unfortunately, the results were not statistically significant. Only acceleration time of the left shoulder in the arm flexion movement in males was significant. Despite this, once the muscular groups are similar for the listed strength variables, the swimmer’s capability to produce force out of water seems to help them perform better in the water.

Effect of 12 Weeks of Resistance Training on Motor Coordination and Dynamic Balance of Older Woman.

Resistance training (RT) is considered a viable strategy to enhance the autonomy and functionality of older populations. We randomized 49 older women (64.2 ± 3.8) into one of two groups: an intervention group (IG) (n = 29) that performed regimented RT or a nontraining control group (CG) (n = 20). The RT protocol was carried out three times a week for both the upper and lower limbs over a 12-week study period. A 30-second arm flexion test was used to test upper limb endurance and a 30-second chair stand test was used to analyze lower limb endurance. Dynamic balance was tested by a Y balance test normalized by leg length. A Soda Pop test was employed to analyze coordination. Results showed significant improvements in IG versus CG in both upper limb (19.50 ± 1.52 vs. 11.40 ± 2.87, p = 0.001) and lower limb muscular endurance (14.90 ± 3.10 vs. 26.56 ± 3.17, p = 0.001). Moreover, the training group showed superior improvements in anterior and posterolateral balance compared to CG (63.9% ± 3.1% to 70.2 ± 2.1 and 88.1 ± 3.9 to 94.2 ± 2.7 with p = 0.001, respectively). There were no significant differences in coordination outcomes between groups. In conclusion, we demonstrate that RT is effective in developing muscular endurance and dynamic balance in postmenopausal women, but does not influence muscular coordination in the measures studied. Study registered in the Brazilian Registry Clinical Trials Registry (No. RBR-7MZ2KR).

Factors Affecting Stability of the Reverse Total Shoulder Arthroplasty: A Cadaveric Biomechanical Study

Background: The overall objective of this study was to investigate whether a reverse shoulder arthroplasty could provide adequate stability to a shoulder even with extreme soft tissue loss. The specific objectives of this study were: to determine if just the deltoid, conjoined tendon, and triceps are sufficient soft tissues to allow a Reverse Shoulder Arthroplasty (RSA) to provide shoulder stability and to determine the influence of load direction, rotation, shoulder position, and polyethylene thickness on RSA stability in this soft-tissue deficient model. Methods: This study utilized six cadaveric shoulders that had all soft tissue removed, with the exception of the deltoid, conjoint tendon, and long head of triceps. A reverse shoulder arthroplasty was then performed (Delta III, DePuy Inc., Warsaw, IN) and an increasing dislocation force was applied perpendicular to the humeral socket centerline until dislocation occurred, or a maximum load of 100 N was reached. This was repeated to measure the effect of four factors: load direction, arm position, polyethylene thickness, and arm rotation on force to dislocation. Results: For load direction, there was an increase in force to dislocate an inferior load direction (p=0.01). There was a lower not dislocated percentage and lower survival for a posterior load direction (p=0.02). For arm position, there was a decrease in force for dislocation and lower survival for both abduction and extension arm positions. There was a higher not dislocated percentage for a flexion arm position (p=0.01). For arm rotation, there was a lower not dislocated percentage and lower survival for an external rotation arm position (p=0.03). There was no statistically significant influence of polyethylene thickness (p=0.26). Conclusion: The deltoid, conjoined tendon, and triceps are sufficient to stabilize an RSA. Load direction, arm position, and arm rotation were all shown to significantly affect stability. Finally, polyethylene thickness may not affect overall RSA stability in this soft-tissue deficient model. Level of Evidence: Basic science study, Biomechanical study.

Association of Peri-ictal Brainstem Posturing With Seizure Severity and Breathing Compromise in Patients With Generalized Convulsive Seizures.

To analyze the association between peri-ictal brainstem posturing semiologies with postictal generalized electroencephalographic suppression (PGES) and breathing dysfunction in generalized convulsive seizures (GCS). In this prospective, multicenter analysis of GCS, ictal brainstem semiology was classified as (1) decerebration (bilateral symmetric tonic arm extension), (2) decortication (bilateral symmetric tonic arm flexion only), (3) hemi-decerebration (unilateral tonic arm extension with contralateral flexion) and (4) absence of ictal tonic phase. Postictal posturing was also assessed. Respiration was monitored with thoracoabdominal belts, video, and pulse oximetry. Two hundred ninety-five seizures (180 patients) were analyzed. Ictal decerebration was observed in 122 of 295 (41.4%), decortication in 47 of 295 (15.9%), and hemi-decerebration in 28 of 295 (9.5%) seizures. Tonic phase was absent in 98 of 295 (33.2%) seizures. Postictal posturing occurred in 18 of 295 (6.1%) seizures. PGES risk increased with ictal decerebration (odds ratio [OR] 14.79, 95% confidence interval [CI] 6.18-35.39, p < 0.001), decortication (OR 11.26, 95% CI 2.96-42.93, p < 0.001), or hemi-decerebration (OR 48.56, 95% CI 6.07-388.78, p < 0.001). Ictal decerebration was associated with longer PGES (p = 0.011). Postictal posturing was associated with postconvulsive central apnea (PCCA) (p = 0.004), longer hypoxemia (p < 0.001), and Spo2 recovery (p = 0.035). Ictal brainstem semiology is associated with increased PGES risk. Ictal decerebration is associated with longer PGES. Postictal posturing is associated with a 6-fold increased risk of PCCA, longer hypoxemia, and Spo2 recovery. Peri-ictal brainstem posturing may be a surrogate biomarker for GCS severity identifiable without in-hospital monitoring. This study provides Class III evidence that peri-ictal brainstem posturing is associated with the GCS with more prolonged PGES and more severe breathing dysfunction.

Muscle co-contraction in an upper limb musculoskeletal model: EMG-assisted vs. standard load-sharing

Estimation of muscle forces in over-actuated musculoskeletal models involves optimal distributions of net joint moments among muscles by a standard load-sharing scheme (SLS). Given that co-contractions of antagonistic muscles are counterproductive in the net joints moments, SLS might underestimate the co-contractions. Muscle co-contractions play crucial roles in stability of the glenohumeral (GH) joint. The aim of this study was to improve estimations of muscle co-contractions by incorporating electromyography (EMG) data into an upper limb musculoskeletal model. To this end, the model SLS was modified to develop an EMG-assisted load-sharing scheme (EALS). EMG of fifteen muscles were measured during arm flexion and abduction on a healthy subject and fed into the model. EALS was compared to SLS in terms of muscle forces, GH joint reaction force, and a stability ratio defined to quantify the GH joint stability. The results confirmed that EALS estimated higher muscle co-contractions compared to the SLS (e.g., above 50 N higher forces for both triceps long and biceps long during arm flexion).

Diferencias en el desempeño motor de los niños con sobrepeso y eutróficos

El objetivo de este estudio fue para comprobar las diferencias de rendimiento en las tareas de Bruininks-Oseretsky motor de la proficiencia de prueba (TBO-2) entre eutrophic y exceso de peso. El total de 98 niños de 8 a 8 años se enrolló en tres entidades privadas de educación en Florianópolis-SC en el estudio. Para evaluar el estado de estado, se han calculado las variables de altura y de masa corporal y se ha calculado el í­ndice de masa corporal (BMI). TBO-2 se utilizó para asesorar el motor de la proficiencia. En el caso de que se produzca un error en el cálculo de los parámetros de distribución, (R = -0.311, p = 0.002), synchronous jump (r = -0.201, p = 0.047), arm flexion (r = -0.240, p = 0.017) y total de las transacciones de BMI TBO-2 score (r = -0.243; p = 0.016). (P = 0.026), sí­ncrono saliente (p = 0.030) y arm flexion (p = 0.019) en eutrophic niños que se compara a los niños de edad. A pesar de que el exceso de peso de los niños se ha encontrado para desempeñarse en el punto de vista de la capacidad de conducción del motor, esta diferencia fue mayor en las tareas de motor especí­fico de las habilidades motoras del lí­mite superior, la coordinación y el balance.

Biomechanical analysis of upper trapezius, erector spinae and brachioradialis fatigue in repetitive manual packaging tasks: Evidence from Chinese express industry workers

This study aims to assess the effects of repetitive motion-induced fatigue during manual packaging on kinematics and muscle activity of the arm, back and shoulder. Eighteen participants performed a 60-min manual packaging task. Electromyography median frequency of RUT, RES, LES and RB decreased by 13.2% (p < 0.05), 12.8% (p < 0.05), 11.3% (p < 0.05) and 21% (p < 0.001), respectively over time. The head flexion and the right upper arm flexion angles significantly (p < 0.001) differed among different packaging sizes, and similar results were observed for left upper arm flexion and rotation. The trunk and pelvis angles significantly (p < 0.05) differed over time under three kinds of packaging. The results showed there was an increase in the rating of perceived exertion from 8.56 to 16.94 (p<0.01) during the task. The outcomes of this study indicate repetitive movements in the manual packaging task resulted in elevated prevalence of muscle discomfort in packaging workers, especially the right brachioradialis. Interventions such as specific work: rest ratios, workplace redesign should be explored to relieve muscle fatigue and discomfort. Relevance to industryFor workers performing repetitive manual packaging tasks, biomechanical analysis of different muscles groups can help in developing appropriate ergonomic interventions.

Cubital tunnel syndrome masked by spinal osteochondrosis

Cubital tunnel syndrome (CTS) is the second most common compression mononeuropathy that is effectively treated. The risk factors for CTS include repetitive arm flexion at the elbow joint and prolonged arm flexion with support on the elbow. The diagnosis of CTS is based on its clinical presentations, the data of neurological examinations, and the results of electroneuromyography and ultrasound examination. The symptoms of the disease progress quickly, therefore the early diagnosis of CTS and its timely treatment are of great importance for the patient's recovery. Unfortunately, patients with CTS are often observed to be erroneously diagnosed with degenerative and dystrophic spinal changes. The paper presents an observation of effective treatment in a young patient who has been suffering from CTS for a long time and been erroneously diagnosed with spinal osteochondrosis. Six months after surgical treatment (for decompression and neurolysis of the left ulnar nerve), the patient regained hand sensitivity and movement. It is concluded that further investigation is necessary to assess predictors of effective surgical treatment in patients with this disease.

Comparisons of physical exposure between workers harvesting apples on mobile orchard platforms and ladders, part 1: Back and upper arm postures

This study compared farmworkers’ exposure to non-neutral postures using a new mobile platform apple harvesting method and the traditional method using ladders. Twenty-four workers were recruited and assigned into three groups: ladder workers (n = 8) picking apples from full trees using a ladder, mobile platform workers (n = 8) picking apples from upper part of the trees while standing on a moving platform, and ground-based mobile platform workers (n = 8) picking apples from lower part of the trees which the mobile platform workers left out. Upper arm and back inclinations were continuously monitored during harvesting using tri-axial accelerometers over full work shifts (~8 h). Upper arm posture was characterized as the percentage of time that upper arm flexion and abduction exceeded 30°, 60°, and 90°. Back posture was characterized as the percentage of time that torso angles (sagittal flexion or lateral bending) exceeded 10°, 20°, and 30°. The 10th, 50th, and 90th postural percentiles were also calculated. The platform workers had lower exposures to upper arm flexion and abduction than the ground and ladder workers. There were no differences in torso angles between the ladder and mobile platform workers; however, the ground workers were exposed to more and greater percentages of time in torso flexions.

Back arm flexion and extension combined with manipulation for the treatment of patient with adhesive scapulohumeral periarthritis

To observe clinical efficacy of back arm flexion and extension combined with manipulation in treating adhesive scapulohumeral periarthritis. From March 2016 to April 2018, 53 patients with adhesive scapulohumeral periarthritis were treated with back arm flexion and extension combined with manipulation, the main symptoms were shoulder pain and limited activity. There were 22 males and 31 females aged from 45 to 71 years old with an average of (51.63±5.79) years;the courses of disease ranged from 3 to 24 months with an average of (8.62±3.73) months. Manipulation treatment was carried out once a week, and back arm flexion and extension were performed for 3 times a day with15 movements each time, totally 4 weeks for a single course. Visual analogue scale (VAS) and Constant-Murley shoulder function score were observed and compared before treatment and one week, one and three months after treatment. All patients were followed up from 3 to 12 months, with an average of (5.91±3.55) months. VAS score before treatment was 4.02±1.46, and was improved to 3.15±1.54, 1.98±1.37, 1.12±0.86 respectively at one week, one and three months after treatment. Constant-Murley score before treatment was 42.70 ±5.72, and improved to 54.25 ±6.34, 67.45 ±6.84, 82.40 ±6.63 at one week, one and three months after treatment respectively;19 patients got excellent result, 22 good, 9 fair and 3 poor. Back arm flexion combined with manipulation for the treatment of adhesive scapulohumeral periarthritis could effectively relieve pain, improve shoulder function, which is a simple effective treatment strategy.

A randomised trial comparing two rehabilitation approaches following reverse total shoulder arthroplasty.

Rehabilitation contributes to post-operative success following reverse total shoulder arthroplasty; however, randomised trials comparing the effectiveness of rehabilitation following reverse total shoulder arthroplasty are lacking. This study sought to determine if early, active mobilisation targeting the deltoid and the external rotator muscles, would exhibit greater improvements in post-operative outcomes compared to a delayed and deltoid-focused mobilisation programme. Patients scheduled for reverse total shoulder arthroplasty were randomly assigned to either an early active or delayed active rehabilitation group. Patient-reported outcomes for pain and function were assessed pre-surgery and at 3, 6 and 12 months post-surgery. Objective measures (Constant Score, range of motion, isometric strength) were assessed at 3, 6 and 12 months post-surgery. Sixty-one patients (63 shoulders) underwent reverse total shoulder arthroplasty. There were no significant interaction effects or between-group differences for any patient-reported outcomes or objective measures at 3, 6 or 12 months post-surgery. However, significantly better (p = 0.019) active arm flexion was observed in the early active group at three months post-surgery. Significantly more patients in the early active group reported improvement in patient-reported function that reached minimal clinically important difference from three to six months post-surgery (p = 0.016). Early, active rehabilitation after reverse total shoulder arthroplasty is safe and effective, and may have early clinical benefits over a conservative, delayed mobilisation programme. Therapy, level 1b. Trial registered 15 June 2016 at www.anzctr.org.au (ACTRN12616000779471).

Strength Adaptions And Body Composition Changes Following High Vs. Low Volume Resistance Training And Detraining

Resistance training (RT) is used for improving strength and body composition. However, it is still under debate whether higher RT volume (HV) is necessary in novices, or if lower volume (LV) is equally effective. In addition, effects of detraining (DTR) following HV and LV RT are not well understood. PURPOSE: To determine the effects of a 12-week HV program (3 sets, 10 repetitions) compared to LV RT (1 set, 10 repetitions) to concentric muscle failure on strength and body composition, followed by four weeks of DTR in male and female subjects. METHODS: Forty-two untrained subjects were randomly assigned to either LV (female n=10; male n=10; age 32.9±11.8y, height 174.2±8.4cm; weight 70.3±13.5kg) or HV RT (female n=11; male n=11; age 33.0±9.6y, height 174.2±11.2cm; weight 72.4±18.1 kg). RT consisted of two RT sessions per week (squat, bench press, arm and leg flexion and extension). Measurements were taken prior to and post RT, and after DTR. Body composition was assessed using BIA. Strength measurement (10-RM) was done using the aforementioned exercises. Six subjects were eliminated from the study due to various reasons, resulting in 36 subjects included for further analysis (HV female n=10, male n=8; LV female n=9, male n=9). Compliance was 100%. Comparisons were made using two-way ANOVA with repeated measures. RESULTS: Both groups increased strength through RT with no difference between groups (squat HV 61.1% vs. LV 59.0%, p<0.001; bench press HV 28.9% vs. LV 31.3%, p<0.001; leg extension HV 54.6% vs. LV 50.2%, p<0.001; leg flexion HV 30.9% vs. LV 30.3%, p<0.001; arm extension HV 51.0% vs. LV 44.8%, p<0.001; arm flexion HV 36.9% vs. LV 31.7%, p<0.001). Body mass (p=0.182), fat mass (p=0.238), and fat-free mass (p=1.000) was unaltered by RT. After DTR strength in arm flexion (p=0.007), arm extension (p=0.001), bench press (p<0.001), and squat (p=0.039) decreased to the same extend in both groups. Leg flexion and extension strength was unaltered following DTR, while fat-free mass increased (p=0.004). CONCLUSION: HV and LV RT was equally effective in untrained subjects to increase strength. Novices could therefore save time with LV, with similar results. Yet, RT alone was not sufficient to change body composition. Following DTR strength gains were still elevated but in some measurements slightly lower than post RT.