Female Age-Related Differences in Biomechanics and Muscle Activity During Descents on the Outstretched Arms

2017 ◽  
Vol 25 (3) ◽  
pp. 474-481 ◽  
Author(s):  
Lauren J. Lattimer ◽  
Joel L. Lanovaz ◽  
Jonathan P. Farthing ◽  
Stéphanie Madill ◽  
Soo Kim ◽  
...  
Keyword(s):  
Muscle Strength ◽  
Older Women ◽  
Energy Absorption ◽  
Age Differences ◽  
Muscle Activity ◽  
Injury Risk ◽  
Biceps Brachii ◽  
Female Age ◽  
Age Related ◽  
Three Body

The purposes of this study were to examine female age differences in: (1) upper extremity (UE) and trunk muscle activity, elbow joint moment, loading force, and UE energy absorption during a controlled forward body descent; and (2) UE muscle strength. Twenty young (mean 24.8 ± 3.4 years) and 20 older (68.4 ± 5.7 years) women were assessed via dynamometry for isometric, concentric, and eccentric UE strength and performed forward descents on force plates at three body lean angles (60°, 45°, and 30° from horizontal). Significant differences (p < .05) were found for muscle strength, biomechanics, and muscle activity. Concentric UE strength averaged 15% lower in older women. At 30° body lean, older women absorbed less energy. Older women had greater biceps brachii activation and less external oblique activation at all body lean angles. Age differences in muscle strength, activation, and energy absorption may contribute to fall-related injury risk.

Chronic Effects of Different Rest Intervals Between Sets on Dynamic and Isometric Muscle Strength and Muscle Activity in Trained Older Women

2017 ◽  
Vol 96 (9) ◽  
pp. 627-633 ◽  
Author(s):  
José Claudio Jambassi Filho ◽  
André Luiz Demantova Gurjão ◽  
Marilia Ceccato ◽  
Alexandre Konig Garcia Prado ◽  
Luiza Herminia Gallo ◽  
...  
Keyword(s):  
Muscle Strength ◽  
Older Women ◽  
Muscle Activity ◽  
Chronic Effects ◽  
Isometric Muscle ◽  
Rest Intervals

Effects of Age and Speed on Peak Lower Extremity Joint Torques During Gait When Controlling Speed and Step Length

2010 ◽  
Author(s):  
Dennis E. Anderson ◽  
Michael L. Madigan
Keyword(s):  
Older Adults ◽  
Young Adults ◽  
Muscle Strength ◽  
Lower Extremity ◽  
Age Differences ◽  
Step Length ◽  
Gait Pattern ◽  
Joint Torques ◽  
Age Related ◽  
Stable Gait

Significant age differences in self-selected gait kinetics have been reported in the literature. These include reduced torque and power at the ankle and increased work at the hip in older adults as compared to young adults [1, 2]. The reasons for these differences are complex and not fully understood. It is possible older adults adapt their gait to a safer, more stable gait pattern [3]. However, differences in gait may also be due to age-related neuromuscular changes such as reduced muscle strength in older adults [4].

scholarly journals Differential Survival of Yearling and Adult Female Mallards and its Relation to Breeding Habitat Conditions

The Condor ◽  
2002 ◽  
Vol 104 (2) ◽  
pp. 297-308 ◽  
Author(s):  
Kevin W. Dufour ◽  
Robert G. Clark
Keyword(s):  
Age Differences ◽  
Anas Platyrhynchos ◽  
Breeding Habitat ◽  
Interactive Effects ◽  
Differential Survival ◽  
Female Age ◽  
South Central ◽  
Age Related ◽  
Breeding Grounds ◽  
Capture Recapture

AbstractInformation on age-specific survivorship is vital to understanding the dynamics of avian populations, but for many avian taxa, little is known about age-related variation in survival beyond the first year of life. We used capture-recapture data from a 16-year field study of female Mallards (Anas platyrhynchos) breeding in south-central Saskatchewan to evaluate survival-rate differences between females marked in their second year (yearlings) and those marked as adults (≥2 years old). Because the breeding season is a period of high mortality for female ducks, we further sought to determine whether age differences in annual survival might vary with wetland conditions on the breeding grounds. Capture-recapture analysis based on extensions of the Cormack-Jolly-Seber model suggested that survival was best modeled to include effects of female age, with yearling females surviving at a higher annual rate (0.58 ± 0.05 SE) than adult females (0.47 ± 0.03 SE). However, additional evidence suggested that age differences in survival were most pronounced in years of low wetland abundance. Recapture rate (indicative perhaps of breeding propensity) was best modeled to include interactive effects of female age and wetland abundance, such that yearling females were recaptured at lower rates than adults in years of low wetland numbers. Collectively, our findings support the hypothesis that reduced breeding by younger females results in elevated probabilities of survival. Whether this pattern reflects reproductive constraint or trade-off decisions on the part of young birds remains to be determined.Supervivencia Diferencial en Hembras Añales y Adultas de Anas platyrhynchos y su Relación con las Condiciones del Hábitat ReproductivoResumen. Para entender la dinámica de las poblaciones de aves es vital contar con información sobre la supervivencia específica por edad, pero para muchos taxa de aves se conoce poco sobre la variación en supervivencia en relación a la edad luego del primer año de vida. Utilizamos datos de 16 años de trabajo de campo sobre captura-recaptura de hembras de Anas platyrhynchos que se reprodujeron en el centro-sur de Saskatchewan. Con estos datos evaluamos las diferencias en la tasa de supervivencia entre hembras marcadas en su segundo año (hembras añales) y aquellas marcadas como adultos (≥2 años de edad). Debido a que la estación reproductiva es un período de alta mortalidad para las hembras, queríamos además determinar si las diferencias de edad en la supervivencia anual variaban en relación a las condiciones de las áreas reproductivas de los humedales. Los análisis de captura-recaptura basados en extensiones del modelo de Cormack-Jolly-Seber sugirieron que la supervivencia era modelada mejor al incluir los efectos de la edad de la hembra, con una tasa anual de supervivencia más alta para hembras añales (0.58 ± 0.05 EE) que para hembras adultas (0.47 ± 0.03 EE). Sin embargo, evidencia adicional sugirió que las diferencias en la supervivencia por edad fueron más pronunciadas en los años con menor número de humedales. La tasa de recaptura (tal vez indicativa de la predisposición a reproducirse) fue modelada mejor al incluir los efectos de la interacción entre edad de la hembra y abundancia de los humedales. De este modo, las hembras añales fueron recapturadas a una tasa menor que las hembras adultas en años con escaso número de humedales. Colectivamente, nuestros resultados apoyan la hipótesis de que una reducción en la reproducción por parte de las hembras más jóvenes da como resultado un aumento en su probabilidad de supervivencia. Aún queda por determinar en las aves jóvenes si este patrón refleja limitantes reproductivas o decisiones de compromiso.

scholarly journals The Effect of Grip Width on Muscle Strength and Electromyographic Activity in Bench Press among Novice- and Resistance-Trained Men

2021 ◽  
Vol 18 (12) ◽  
pp. 6444
Author(s):  
Atle Hole Saeterbakken ◽  
Nicolay Stien ◽  
Helene Pedersen ◽  
Tom Erik Jorung Solstad ◽  
Kristoffer Toldnes Cumming ◽  
...  
Keyword(s):  
Muscle Strength ◽  
Muscle Activity ◽  
Bench Press ◽  
Biceps Brachii ◽  
The Other ◽  
Electromyographic Activity ◽  
Triceps Brachii ◽  
Repetition Maximum ◽  
Anterior Deltoid ◽  
Group Comparisons

Background: This study compared the muscle activity and six repetition maximum (6-RM) loads in bench press with narrow, medium, and wide grip widths with sub-group comparisons of resistance-trained (RT) and novice-trained (NT) men. Methods: After two familiarization sessions, twenty-eight subjects lifted their 6-RM loads with the different grip widths with measurement of electromyographic activity. Results: Biceps brachii activity increased with increasing grip width, whereas wide grip displayed lower triceps brachii activation than medium and narrow. In the anterior deltoid, greater activity was observed using a medium compared to narrow grip. Similar muscle activities were observed between the grip widths for the other muscles. For the RT group, greater biceps brachii activity with increasing grip width was observed, but only greater activity was observed in the NT group between narrow and wide. Comparing wide and medium grip width, the RT group showed lower triceps activation using a wide grip, whereas the NT group showed lower anterior deltoid activation using a narrow compared to medium grip. Both groups demonstrated lower 6-RM loads using a narrow grip compared to the other grips. Conclusion: Grip widths affect both 6-RM loads and triceps brachii, biceps brachii, and anterior deltoid activity especially between wide and narrow grip widths.

scholarly journals Age-Related Increase in Electromyography Burst Activity in Males and Females

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Olga Theou ◽  
Darl Edwards ◽  
Gareth R. Jones ◽  
Jennifer M. Jakobi
Keyword(s):  
Muscle Activity ◽  
Biceps Brachii ◽  
Vastus Lateralis ◽  
Activity Patterns ◽  
Functional Decline ◽  
Burst Activity ◽  
Triceps Brachii ◽  
Old Adults ◽  
Age Related ◽  
Males And Females

The rapid advancement of electromyography (EMG) technology facilitates measurement of muscle activity outside the laboratory during daily life. The purpose of this study was to determine whether bursts in EMG recorded over a typical 8-hour day differed between young and old males and females. Muscle activity was recorded from biceps brachii, triceps brachii, vastus lateralis, and biceps femoris of 16 young and 15 old adults using portable surface EMG. Old muscles were active 16–27% of the time compared to 5–9% in young muscles. The number of bursts was greater in old than young adults and in females compared to males. Burst percentage and mean amplitude were greater in the flexor muscles compared with the extensor muscles. The greater burst activity in old adults coupled with the unique activity patterns across muscles in males and females provides further understanding of how changes in neuromuscular activity effects age-related functional decline between the sexes.

scholarly journals Stigma mastery in people living with HIV: gender similarities and theory

2021 ◽  
Author(s):  
Charles Patrick Namisi ◽  
John C. Munene ◽  
Rhoda K. Wanyenze ◽  
Anne R. Katahoire ◽  
Rosalinda M. Parkes-Ratanshi ◽  
...  
Keyword(s):  
Older Women ◽  
Social Exclusion ◽  
Theoretical Framework ◽  
People Living With Hiv ◽  
Negative Effects ◽  
Hiv Diagnosis ◽  
Cross Sectional ◽  
Age Related ◽  
Related Stigma ◽  
Living With Hiv

Abstract Aims This study aimed to determine the prevalence of, factors associated with, and to build a theoretical framework for understanding Internalsed HIV-related Stigma Mastery (IHSM). Methods A cross-sectional study nested within a 2014 Stigma Reduction Cohort in Uganda was used. The PLHIV Stigma Index version 2008, was used to collect data from a random sample of 666 people living with HIV (PLHIV) stratified by gender and age. SPSS24 with Amos27 softwares were used to build a sequential-mediation model. Results The majority of participants were women (65%), aged ≥ 40 years (57%). Overall, IHSM was 45.5% among PLHIV, that increased with age. Specifically, higher IHSM correlated with men and older women “masculine identities” self-disclosure of HIV-diagnosis to family, sharing experiences with peers. However, lower IHSM correlated with feminine gender, the experience of social exclusion stress, fear of future rejection, and fear of social intimacy. Thus, IHSM social exclusion with its negative effects and age-related cognition are integrated into a multidimensional IHSM theoretical framework with a good model-to-data fit. Conclusion Internalised HIV-related Stigma Mastery is common among men and older women. Specificially, “masculine identities” self-disclose their own HIV-positive diagnosis to their family, share experiences with peers to create good relationships for actualising or empowerment in stigma mastery. However, social exclusion exacerbates series of negative effects that finally undermine stigma mastery by young feminine identities. Thus, stigma mastery is best explained by an integrated empowerment framework, that has implications for future practice, policy, and stigma-related research that we discuss.

scholarly journals Gait disturbances and muscle dysfunction in fibroblast growth factor 2 knockout mice

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
C. Homer-Bouthiette ◽  
L. Xiao ◽  
Marja M. Hurley
Keyword(s):  
Skeletal Muscle ◽  
Growth Factor ◽  
Muscle Strength ◽  
Fibroblast Growth Factor ◽  
Muscle Function ◽  
Fibroblast Growth Factor 2 ◽  
Fibroblast Growth ◽  
Skeletal Muscle Function ◽  
Age Related ◽  
Gait Disturbances

AbstractFibroblast growth factor 2 (FGF2) is important in musculoskeletal homeostasis, therefore the impact of reduction or Fgf2 knockout on skeletal muscle function and phenotype was determined. Gait analysis as well as muscle strength testing in young and old WT and Fgf2KO demonstrated age-related gait disturbances and reduction in muscle strength that were exacerbated in the KO condition. Fgf2 mRNA and protein were significantly decreased in skeletal muscle of old WT compared with young WT. Muscle fiber cross-sectional area was significantly reduced with increased fibrosis and inflammatory infiltrates in old WT and Fgf2KO vs. young WT. Inflammatory cells were further significantly increased in old Fgf2KO compared with old WT. Lipid-related genes and intramuscular fat was increased in old WT and old Fgf2KO with a further increase in fibro-adipocytes in old Fgf2KO compared with old WT. Impaired FGF signaling including Increased β-Klotho, Fgf21 mRNA, FGF21 protein, phosphorylated FGF receptors 1 and 3, was observed in old WT and old Fgf2KO. MAPK/ ERK1/2 was significantly increased in young and old Fgf2KO. We conclude that Fgf2KO, age-related decreased FGF2 in WT mice, and increased FGF21 in the setting of impaired Fgf2 expression likely contribute to impaired skeletal muscle function and sarcopenia in mice.

scholarly journals Femicide Fatal Risk Factors: A Last Decade Comparison between Italian Victims of Femicide by Age Groups

2020 ◽  
Vol 17 (21) ◽  
pp. 7953
Author(s):  
Anna Sorrentino ◽  
Chiara Guida ◽  
Vincenza Cinquegrana ◽  
Anna Costanza Baldry
Keyword(s):  
Risk Factors ◽  
Older Women ◽  
Violence Against Women ◽  
Age Differences ◽  
Policy Implication ◽  
Age Groups ◽  
Intimate Partner ◽  
International Studies ◽  
Wide Spread ◽  
Female Victims

Femicide is a wide-spread lethal form of violence against women. Despite its diffusion, to date, very few studies analyzed possible victims’ age differences in regard to fatal risk factors for femicide. To this aim, we carried out archive research on Italian femicide cases in the last decade, by comparing prior types of violence suffered and motives for femicide, which are considered crucial fatal risk factors for femicide, across adolescent/young (15–24 years), adults (25–64 years) and older women (65–93 years). From 2010 to 2019 we found 1207 female victims. Characteristics of victims, perpetrators, and their relationship were consistent with those found by international studies and underlined that the majority of femicides were perpetrated by an intimate partner. The results regarding fatal risk factors comparisons across age groups showed the existence of significant differences regarding both types of violence suffered prior to femicide and motives for femicide. The results are discussed in terms of policy implication and intervention.

Analysis of Muscle Activity Using Surface Electromyography for Muscle Performance in Manual Lifting Task

2014 ◽  
Vol 564 ◽  
pp. 644-649 ◽  
Author(s):  
Halim Isa ◽  
Rawaida ◽  
Seri Rahayu Kamat ◽  
A. Rohana ◽  
Adi Saptari ◽  
...  
Keyword(s):  
Muscle Activity ◽  
Surface Electromyography ◽  
Biceps Brachii ◽  
Twist Angle ◽  
Erector Spinae ◽  
Manual Lifting ◽  
Experienced Fatigue ◽  
Left And Right ◽  
Lifting Task ◽  
Load Mass

In industries, manual lifting is commonly practiced even though mechanized material handling equipment are provided. Manual lifting is used to transport or move products and goods to a desired place.Improper lifting techniquescontribute to muscle fatigue and low back pain that can lead to work efficiency and low productivity.The objective of this study were to analyze muscle activity in the left and right Erector Spinae, and left and right Biceps Brachii of five female subjects while performing manual lifting taskwithdifferent load mass, lifting height and twist angle.The muscle activitywere measured and analyzed using surface electromyography (sEMG).This study found that the right Biceps Brachii, right and left Erector Spinae experienced fatigue while performingasymmetric lifting (twist angle = 90°) at lifting height of 75 cm and 140 cm with load mass of 5 kg and 10 kg. Meanwhile, the left Biceps Brachii experienced fatigue when the lifting task was set at lifting height of 75 cm, load mass of 5 kg and twist angle of 90°.The load mass and lifting height has a significant influence to Mean Power Frequency (MPF) for left Biceps Brachii, left and right Erector Spinae. This study concluded that reducing the load mass can increase the muscles performance which can extend the transition-to-fatigue stage in the left and right Biceps Brachii and Erector Spinae.

Sign in / Sign up

Export Citation Format

Share Document