scholarly journals Biceps Femoris Activation during Hamstring Strength Exercises: A Systematic Review

2021 ◽  
Vol 18 (16) ◽  
pp. 8733
Author(s):  
Luis Llurda-Almuzara ◽  
Noé Labata-Lezaun ◽  
Carlos López-de-Celis ◽  
Ramón Aiguadé-Aiguadé ◽  
Sergi Romaní-Sánchez ◽  
...  
Keyword(s):  
Systematic Review ◽  
Isometric Contraction ◽  
Biceps Femoris ◽  
Cochrane Library ◽  
Exclusion Criteria ◽  
Maximal Voluntary Isometric Contraction ◽  
Cross Sectional ◽  
Strength Exercises ◽  
Long Head ◽  
Biceps Femoris Long Head

Background: The aim of the study was to systematically evaluate the biceps femoris long head activation across cross-sectional hamstring strength exercise studies. Methods: A systematic review design was followed. The search strategy conducted in PubMed, Cochrane Library, and Web of Sciences databases found a total of 3643 studies. Once inclusion and exclusion criteria were applied, 29 studies were finally included in this systematic review. A total of 507 participants and 114 different exercises were analyzed. Exercises were evaluated individually and grouped into several categories: Nordics, isokinetic exercises, lunges, squats, deadlifts, good mornings, hip thrusts, bridges, leg curls, swings, hip and back extensions, and others. Results: Results showed the isokinetic and Nordic exercises as the categories with highest biceps femoris activation (>60% of Maximal Voluntary Isometric Contraction). Nordic hamstring exercise ankle dorsiflexion was the exercise that achieved the highest biceps femoris long head activation (128.1% of its Maximal Voluntary Isometric Contraction). Conclusions: The results from this systematic review suggest that isokinetic and Nordic exercises seem to be the best option to activate biceps femoris long head. Future studies evaluating the implementation of these exercises in prevention programs are needed.

scholarly journals Effects of knee flexor submaximal isometric contraction until exhaustion on semitendinosus and biceps femoris long head shear modulus in healthy individuals

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Bruno Mendes ◽  
Telmo Firmino ◽  
Raúl Oliveira ◽  
Tiago Neto ◽  
Carlos Cruz-Montecinos ◽  
...  
Keyword(s):  
Isometric Contraction ◽  
Shear Wave Elastography ◽  
Biceps Femoris ◽  
Time To Exhaustion ◽  
Healthy Individuals ◽  
Maximal Voluntary Isometric Contraction ◽  
Knee Flexor ◽  
Task Time ◽  
Long Head ◽  
Biceps Femoris Long Head

Abstract This study examined whether a knee flexor isometric contraction at 20% of maximal voluntary isometric contraction until exhaustion would alter the biceps femoris long head (BFlh) and semitendinosus (ST) active stiffness, assessed using ultrasound-based shear wave elastography. Twelve healthy individuals participated in 2 sessions separated by 7 days. Time to exhaustion was similar in both sessions (day 1: 443.8 ± 192.5 s; day 2: 474.6 ± 131.7 s; p = 0.323). At the start of the fatigue task, the ST showed greater active stiffness than the BFlh (p < 0.001), with no differences between days (p = 0.08). The ST active stiffness then decreased from 40% of the task time to exhaustion (− 2.2 to − 13.3%, p = 0.027) until the end of the task (− 16.1 to − 22.9%, p = 0.012), while no significant changes were noted in the BFlh (p = 0.771). Immediately after the fatigue task, a decrease in active stiffness was observed in the ST (− 11.8 to − 17.8%, p < 0.001), but not in the BFlh (p = 0.551). Results were consistent between the 2 testing sessions (p = 0.07–0.959). The present results indicate that fatigue alters the hamstring active stiffness pattern.

Poststretch Isometric Contractions of the Hamstrings: Just a Brief Stretch to Achieve Supramaximal Isometric Force

2021 ◽  
pp. 1-7
Author(s):  
Neil Chapman ◽  
John William Whitting ◽  
Suzanne Broadbent ◽  
Zachary Crowley-McHattan ◽  
Rudi Meir
Keyword(s):  
Isometric Contraction ◽  
Knee Flexion ◽  
Isometric Force ◽  
Biceps Femoris ◽  
Isometric Contractions ◽  
Maximal Voluntary Isometric Contraction ◽  
Hamstring Strain ◽  
Long Head ◽  
Biceps Femoris Long Head ◽  
Knee Flexors

Hamstring strain injuries are common in sport. Supramaximal eccentric or high-intensity isometric contractions are favored in hamstring strain injury prevention. The effect of combining these contraction modes in such prevention programs as a poststretch isometric contraction is unknown. Poststretch isometric contractions incorporate an active stretch and result in greater final isometric force than isometric contractions at comparable joint angles. This study compared torque and muscle activation levels between maximal voluntary isometric contraction and maximal poststretch isometric contractions of the knee flexors. Participants (n = 9) completed baseline maximal voluntary isometric contraction at 150° knee flexion and maximal poststretch isometric contractions at 120° knee flexion actively stretching at 60°/s to 150° knee flexion for final isometric contraction. Torque of the knee flexors and surface electromyography root mean square (sEMGRMS) of biceps femoris long head were simultaneously recorded and compared between baseline and poststretch isometric at 150° knee flexion. Torque was 14% greater in the poststretch isometric condition compared with baseline maximal voluntary isometric contraction (42.45 [20.75] N·m, 14% [22.18%], P < .001) without increase in sEMGRMS of biceps femoris long head (−.03 mV, ±.06, P = .130, d = .93). Poststretch isometric contractions resulted in supramaximal levels of poststretch isometric torque without increased activation of biceps femoris long head.

Muscle- and Region-Specific Associations Between Muscle Size and Muscular Strength During Hip Extension and Knee Flexion in the Hamstrings

2021 ◽  
pp. 1-6
Author(s):  
Raki Kawama ◽  
Masamichi Okudaira ◽  
Hirohiko Maemura ◽  
Satoru Tanigawa
Keyword(s):  
Knee Flexion ◽  
Muscular Strength ◽  
Sports Injuries ◽  
Biceps Femoris ◽  
Muscle Size ◽  
Cross Sectional ◽  
Long Head ◽  
Hip Extension ◽  
Flexion Strength ◽  
Biceps Femoris Long Head

Context: Strength deficits of the hamstrings following sports injuries decrease athletic performance and increase the risk of injury recurrence. Previous studies have shown a high correlation between the muscular strength during hip-extension and knee-flexion and total muscle size of the hamstrings. However, it remains unclear which region of the individual hamstring muscles is closely associated with muscular strength. Objective: To investigate the relationship between the size of each region of the individual hamstring muscles and muscular strength during hip extension and knee flexion. Design: Within-subject repeated measures. Setting: University laboratory. Participants: Twenty healthy young male volunteers who regularly engaged in sports activities. Outcome Measures: Anatomical cross-sectional areas were acquired from the proximal, middle, and distal regions of the biceps femoris long head, biceps femoris short head, semitendinosus, and semimembranosus. Hip-extension and knee-flexion strength were measured during maximal voluntary isometric and concentric contractions (angular velocities of 60°/s and 180°/s). Results: The anatomical cross-sectional area of the distal regions in biceps femoris long head (r = .525–.642) and semitendinosus (r = .567) were significantly correlated with hip-extension strength under all conditions and only at an angular velocity of 180°/s, respectively. Meanwhile, anatomical cross-sectional areas of the distal regions in biceps femoris short head (r = .587–.684) and semimembranosus (r = .569–.576) were closely associated with knee-flexion strength under all conditions. Conclusion: These results suggest that muscle size in the distal regions of biceps femoris long head and semitendinosus greatly contributes to the production of hip-extension strength, whereas that of biceps femoris short head and semimembranosus significantly contributes to the generation of knee-flexion strength. These findings could be useful for designing training and rehabilitation programs to efficiently improve strength deficits following sports injuries such as strain injury and anterior cruciate ligament tears.

scholarly journals Effect of Nordic Hamstring Exercise Training on Knee Flexors Eccentric Strength and Fascicle Length: A Systematic Review and Meta-Analysis

2020 ◽  
pp. 1-10
Author(s):  
Diulian Muniz Medeiros ◽  
César Marchiori ◽  
Bruno Manfredini Baroni
Keyword(s):  
Systematic Review ◽  
Confidence Interval ◽  
Randomized Clinical Trials ◽  
Evidence Synthesis ◽  
Meta Analysis ◽  
Biceps Femoris ◽  
Fascicle Length ◽  
Long Head ◽  
Biceps Femoris Long Head ◽  
Knee Flexors

Context: Nordic hamstring exercise (NHE) has been widely employed to prevent hamstring strain injuries. However, it is still not clear which adaptations are responsible for the NHE preventive effects. Objectives: The aim of this study was to investigate the effects of NHE on knee flexors eccentric strength and fascicle length. Evidence Acquisition: The search strategy included MEDLINE, PEDro, and Cochrane CENTRAL from inception to April 2020. Randomized clinical trials that have analyzed the effects of NHE training on hamstring eccentric strength and/or fascicle length were included. Evidence Synthesis: From the 1932 studies identified, 12 were included in the systematic review, and 9 studies presented suitable data for the meta-analysis. All studies demonstrated strength increments in response to NHE training (10%–15% and 16%–26% in tests performed on the isokinetic dynamometer and on the NHE device, respectively), as well as significant enhancement of biceps femoris long head fascicle length (12%–22%). Meta-analysis showed NHE training was effective to increase knee flexors eccentric strength assessed with both isokinetic tests (0.68; 95% confidence interval, 0.29 to 1.06) and NHE tests (1.11; 95% confidence interval, 0.62 to 1.61). NHE training was also effective to increase fascicle length (0.97; 95% confidence interval, 0.46 to 1.48). Conclusions: NHE training has the potential of increasing both knee flexors eccentric strength and biceps femoris long head fascicle length.

Executive functions in children with heart disease: a systematic review and meta-analysis

2021 ◽  
pp. 1-9
Author(s):  
William M. Jackson ◽  
Nicholas Davis ◽  
Johanna Calderon ◽  
Jennifer J. Lee ◽  
Nicole Feirsen ◽  
...  
Keyword(s):  
Systematic Review ◽  
Executive Functions ◽  
Data Extraction ◽  
Meta Analysis ◽  
Executive Dysfunction ◽  
Cochrane Library ◽  
Planning Problem ◽  
Healthy Controls ◽  
Cross Sectional ◽  
Increased Risk

Abstract Context: People with CHD are at increased risk for executive functioning deficits. Meta-analyses of these measures in CHD patients compared to healthy controls have not been reported. Objective: To examine differences in executive functions in individuals with CHD compared to healthy controls. Data sources: We performed a systematic review of publications from 1 January, 1986 to 15 June, 2020 indexed in PubMed, CINAHL, EMBASE, PsycInfo, Web of Science, and the Cochrane Library. Study selection: Inclusion criteria were (1) studies containing at least one executive function measure; (2) participants were over the age of three. Data extraction: Data extraction and quality assessment were performed independently by two authors. We used a shifting unit-of-analysis approach and pooled data using a random effects model. Results: The search yielded 61,217 results. Twenty-eight studies met criteria. A total of 7789 people with CHD were compared with 8187 healthy controls. We found the following standardised mean differences: −0.628 (−0.726, −0.531) for cognitive flexibility and set shifting, −0.469 (−0.606, −0.333) for inhibition, −0.369 (−0.466, −0.273) for working memory, −0.334 (−0.546, −0.121) for planning/problem solving, −0.361 (−0.576, −0.147) for summary measures, and −0.444 (−0.614, −0.274) for reporter-based measures (p < 0.001). Limitations: Our analysis consisted of cross-sectional and observational studies. We could not quantify the effect of collinearity. Conclusions: Individuals with CHD appear to have at least moderate deficits in executive functions. Given the growing population of people with CHD, more attention should be devoted to identifying executive dysfunction in this vulnerable group.

328 Insomnia in older HIV patients: a systematic review

SLEEP ◽  
2021 ◽  
Vol 44 (Supplement_2) ◽  
pp. A131-A131
Author(s):  
Igor Freire ◽  
Miguel Meira e Cruz ◽  
Cristina Salles
Keyword(s):  
Systematic Review ◽  
General Population ◽  
Animal Studies ◽  
Advanced Age ◽  
Cochrane Library ◽  
Hiv Positive ◽  
Sleep Difficulty ◽  
Cross Sectional ◽  
Previous Diagnosis ◽  
Worse Prognosis

Abstract Introduction Insomnia is a common sleep disorder in elderly. Although the HIV-positive population have a similar life expectancy when compared to the general population, some factors may interact with immunity conditions and therefore contribute to a worse prognosis. Little is known however, about the frequency of insomnia in older HIV-positive patients. OBJECTIVE: To systematic review the prevalence of insomnia in older HIV-positive patients. Methods Systematic Review. Several databases were consulted (MEDLINE-PubMed, Embase, Cochrane Library, CINAHL, Web of Science, Scopus, SciELO, LILACS, and VHL) and manual searches were performed. The terms used for the search were related to prevalence, HIV, insomnia, and advanced age. The inclusion criteria were: cross-sectional, cohort, and longitudinal studies. The accepted data were in patients with the previous diagnosis of HIV in advanced age, those over 50 years; studies that report the frequency of insomnia or insomnia symptoms (accepted symptoms: difficulty in starting sleep, difficulty in maintaining sleep, multiple awakenings during sleep and early awakening). The criteria for exclusion were: clinical trials, animal studies, letters, abstracts, conference proceedings, studies with other sleep scales that did not include insomnia. Results There were 2805 publications found in the database and a further 10 articles were included manually. Of this total, four were included in this review, resulting in a total of 2,227 participants. The prevalence of insomnia in HIV-positive patients over 50 years varied from 12.5% to 76.5%. Conclusion The frequency of insomnia was higher in the profile of the population studied than in the general population. This should be clinically relevant in order to adequately treat and impact on the prognosis of those patient. Support (if any):

scholarly journals Sedentary behaviour among general practitioners: a systematic review

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Richard S. Mayne ◽  
Nigel D. Hart ◽  
Neil Heron
Keyword(s):  
Systematic Review ◽  
Sedentary Behaviour ◽  
General Practitioners ◽  
Sedentary Time ◽  
Grey Literature ◽  
Sitting Time ◽  
Cochrane Library ◽  
Cross Sectional ◽  
The Cochrane Library ◽  
Activity Questionnaire

Abstract Background Sedentary behaviour is when someone is awake, in a sitting, lying or reclining posture and is an independent risk factor for multiple causes of morbidity and mortality. A dose-response relationship has been demonstrated, whereby increasing sedentary time corresponds with increasing mortality rate. This study aimed to identify current levels of sedentary behaviour among General Practitioners (GPs), by examining and synthesising how sedentary behaviour has been measured in the primary care literature. Methods A systematic review was conducted to identify studies relating to levels of sedentary behaviour among GPs. Searches were performed using Medline®, Embase®, PscycINFO, Web of Science and the Cochrane Library, from inception of databases until January 2020, with a subsequent search of grey literature. Articles were assessed for quality and bias, with extraction of relevant data. Results The search criteria returned 1707 studies. Thirty four full texts were reviewed and 2 studies included in the final review. Both were cross-sectional surveys using self-reported estimation of sedentary time within the International Physical Activity Questionnaire (IPAQ). Keohane et al. examined GP trainees and GP trainers in Ireland. 60% reported spending in excess of 7 h sitting each day, 24% between 4 and 7 h, and 16% less than or equal to 4 h. Suija et al. examined female GPs in Estonia. The mean reported daily sitting time was 6 h and 36 min, with 56% sitting for over 6 h per day. Both studies were of satisfactory methodological quality but had a high risk of bias. Conclusion There is a paucity of research examining current levels of sedentary behaviour among GPs. Objective data is needed to determine GPs’ current levels of sedentary behaviour, particularly in light of the increase in remote consulting as a result of the COVID-19 pandemic.

Influence of submaximal isometric contractions of the hamstrings on electromyography activity and force while functioning as hip extensors

2020 ◽  
pp. 1-8
Author(s):  
Dasom Oh ◽  
Wootaek Lim
Keyword(s):  
Prone Position ◽  
Supine Position ◽  
Isometric Contraction ◽  
Muscle Length ◽  
Biceps Femoris ◽  
Emg Activity ◽  
Isometric Contractions ◽  
Significant Difference ◽  
Extension Force ◽  
Long Head

BACKGROUND: Although the medial and lateral hamstrings are clearly distinct anatomically and have different functions in the transverse plane, they are often considered as one muscle during rehabilitation. OBJECTIVE: The purpose of the study was to compare the electromyographic (EMG) activity between the prone position and the supine position during maximal isometric contraction and to additionally confirm the effect of submaximal isometric contractions on EMG activity of medial and lateral hamstrings, and force. METHODS: In the prone position, EMG activities of the long head of biceps femoris (BFLH) and semitendinosus (ST) were measured during the maximal isometric contraction. In the supine position, hip extension force with EMG activity were measured during the maximal and the submaximal isometric contractions. RESULTS: EMG activity in the prone position was significantly decreased in the supine position. In the supine position, there was a significant difference between the BFLH and ST during the maximal isometric contraction, but not during the submaximal isometric contractions. CONCLUSIONS: The dependence on the hamstrings could be relatively lower during hip extensions. When the medial and lateral hamstrings are considered separately, the lateral hamstrings may show a more active response, with increased muscle length, in clinical practice.

scholarly journals Poor agreement between ultrasound and inbuilt diffusion tensor MRI measures of biceps femoris long head fascicle length

2018 ◽  
Vol 2 (2) ◽  
pp. 58-63 ◽  
Author(s):  
Fearghal P. Behan ◽  
Robin Vermeulen ◽  
Tessa Smith ◽  
Javier Arnaiz ◽  
Rodney Whiteley ◽  
...  
Keyword(s):  
Diffusion Tensor ◽  
Biceps Femoris ◽  
Diffusion Tensor Mri ◽  
Poor Agreement ◽  
Fascicle Length ◽  
Long Head ◽  
Biceps Femoris Long Head

scholarly journals Factors Associated with Depression and Anxiety in Adults ≥60 Years Old during the COVID-19 Pandemic: A Systematic Review

2021 ◽  
Vol 18 (22) ◽  
pp. 11859
Author(s):  
Gianluca Ciuffreda ◽  
Sara Cabanillas-Barea ◽  
Andoni Carrasco-Uribarren ◽  
María Isabel Albarova-Corral ◽  
María Irache Argüello-Espinosa ◽  
...  
Keyword(s):  
Systematic Review ◽  
Female Gender ◽  
Cochrane Library ◽  
Poor Sleep ◽  
Depression And Anxiety ◽  
Poor Sleep Quality ◽  
Cross Sectional ◽  
Factors Associated ◽  
Population Prevalence ◽  
Cross Sectional Design

COVID-19 represents a threat to public health and the mental health of the aged population. Prevalence and risk factors of depression and anxiety have been reported in previous reviews in other populations; however, a systematic review on the factors associated with depression and anxiety in older adults is not currently present in the literature. We searched PubMed, Embase, Scopus, ProQuest Psychology Database, Science Direct, Cochrane Library and SciELO databases (23 February 2021). The results were obtained by entering a combination of MeSH or Emtree terms with keywords related to COVID-19, elderly, depression and anxiety in the databases. A total of 11 studies were included in the systematic review. Female gender, loneliness, poor sleep quality and poor motor function were identified as factors associated with both depression and anxiety. Aspects related to having a stable and high monthly income represent protective factors for both depression and anxiety, and exercising was described as protective for depression. This study synthesised information and analysed the main factors associated with depression and anxiety in the older population during the COVID-19 pandemic. However, the cross-sectional design of most of the included studies does not allow a causal relationship between the factors analysed and depression or anxiety.

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