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1.
BMC Public Health ; 18(1): 1278, 2018 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-30453966

RESUMEN

BACKGROUND: Free VMMC services have been available in Uganda since 2010. However, uptake in Northern Uganda remains disproportionately low. We aimed to determine if this is due to men's insufficient knowledge on VMMC, and if women's knowledge on VMMC has any association with VMMC status of their male sexual partners. METHODS: In this cross sectional study, participants were asked their circumcision status (or that of their male sexual partner for female respondents) and presented with 14 questions on VMMC benefits, procedure, risk, and misconceptions. Chi square tests or fisher exact tests were used to compare circumcision prevalence among those who gave correct responses versus those who failed to and if p < 0.05, the comparison groups were balanced with propensity score weights in modified poisson models to estimate prevalence ratios, PR. RESULTS: A total of 396 men and 50 women were included in the analyses. Circumcision was 42% less prevalent among males who failed to reject the misconception that VMMC reduces sexual performance (PR = 0.58, 95% CI 0.38-0.89, p = 0.012), and less prevalent among male sexual partners of females who failed to reject the same misconception (PR = 0.22, 95% CI = 0.07-0.76, p = 0.016). Circumcision was also 35% less prevalent among male respondents who failed to reject the misconception that VMMC increases a man's desire for more sexual partners i.e. promiscuity (PR = 0.65, 95% CI = 0.46-0.92, p = 0.014). CONCLUSION: Misconceptions regarding change in sexual drive or performance were associated with circumcision status in this population, while knowledge of VMMC benefits, risks and procedure was not.


Asunto(s)
Circuncisión Masculina , Conocimientos, Actitudes y Práctica en Salud , Programas Voluntarios , Adolescente , Adulto , Circuncisión Masculina/estadística & datos numéricos , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Uganda , Adulto Joven
2.
J Sports Sci ; 35(15): 1556-1564, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27624557

RESUMEN

This study assessed kinematic differences between different foot strike patterns and their relationship with peak vertical instantaneous loading rate (VILR) of the ground reaction force (GRF). Fifty-two runners ran at 3.2 m · s-1 while we recorded GRF and lower limb kinematics and determined foot strike pattern: Typical or Atypical rearfoot strike (RFS), midfoot strike (MFS) of forefoot strike (FFS). Typical RFS had longer contact times and a lower leg stiffness than Atypical RFS and MFS. Typical RFS showed a dorsiflexed ankle (7.2 ± 3.5°) and positive foot angle (20.4 ± 4.8°) at initial contact while MFS showed a plantar flexed ankle (-10.4 ± 6.3°) and more horizontal foot (1.6 ± 3.1°). Atypical RFS showed a plantar flexed ankle (-3.1 ± 4.4°) and a small foot angle (7.0 ± 5.1°) at initial contact and had the highest VILR. For the RFS (Typical and Atypical RFS), foot angle at initial contact showed the highest correlation with VILR (r = -0.68). The observed higher VILR in Atypical RFS could be related to both ankle and foot kinematics and global running style that indicate a limited use of known kinematic impact absorbing "strategies" such as initial ankle dorsiflexion in MFS or initial ankle plantar flexion in Typical RFS.


Asunto(s)
Pie/fisiología , Carrera/fisiología , Adulto , Tobillo/fisiología , Fenómenos Biomecánicos , Femenino , Marcha/fisiología , Humanos , Rodilla/fisiología , Masculino , Muslo/fisiología , Soporte de Peso
3.
J Appl Biomech ; 33(6): 431-436, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-28657790

RESUMEN

In running, foot contact patterns (rear-, mid-, or forefoot contact) influence impact intensity and initial ankle and foot kinematics. The aim of the study was to compare impact intensity and its spatial distribution under the foot between different foot contact patterns. Forty-nine subjects ran at 3.2 m·s-1 over a level runway while ground reaction forces (GRF) and shoe-surface pressures were recorded and foot contact pattern was determined. A 4-zone footmask (forefoot, midfoot, medial and lateral rearfoot) assessed the spatial distribution of the vertical GRF under the foot. We calculated peak vertical instantaneous loading rate of the GRF (VILR) per foot zone as the impact intensity measure. Midfoot contact patterns were shown to have the lowest, and atypical rearfoot contact patterns the highest impact intensities, respectively. The greatest local impact intensity was mainly situated under the rear- and midfoot for the typical rearfoot contact patterns, under the midfoot for the atypical rearfoot contact patterns, and under the mid- and forefoot for the midfoot contact patterns. These findings indicate that different foot contact patterns could benefit from cushioning in different shoe zones.


Asunto(s)
Articulación del Tobillo/fisiología , Pie/fisiología , Carrera/fisiología , Zapatos , Adulto , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Presión , Soporte de Peso/fisiología
4.
J Appl Biomech ; 30(4): 521-8, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24615336

RESUMEN

The purpose of this study was to: (1) investigate how kinematic patterns are adjusted while running in footwear with THIN, MEDIUM, and THICK midsole thicknesses and (2) determine if these patterns are adjusted over time during a sustained run in footwear of different thicknesses. Ten male heel-toe runners performed treadmill runs in specially constructed footwear (THIN, MEDIUM, and THICK midsoles) on separate days. Standard lower extremity kinematics and acceleration at the tibia and head were captured. Time epochs were created using data from every 5 minutes of the run. Repeated-measures ANOVA was used (P < .05) to determine differences across footwear and time. At touchdown, kinematics were similar for the THIN and MEDIUM conditions distal to the knee, whereas only the THIN condition was isolated above the knee. No runners displayed midfoot or forefoot strike patterns in any condition. Peak accelerations were slightly increased with THIN and MEDIUM footwear as was eversion, as well as tibial and thigh internal rotation. It appears that participants may have been anticipating, very early in their run, a suitable kinematic pattern based on both the length of the run and the footwear condition.


Asunto(s)
Aceleración , Articulación del Tobillo/fisiología , Marcha/fisiología , Articulación de la Rodilla/fisiología , Carrera/fisiología , Zapatos , Equipo Deportivo , Adaptación Fisiológica/fisiología , Diseño de Equipo , Análisis de Falla de Equipo , Hábitos , Resistencia Física/fisiología , Rango del Movimiento Articular/fisiología , Estrés Mecánico
5.
Biol Pharm Bull ; 35(12): 2180-5, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23207770

RESUMEN

Ethyl sulfate, a minor and direct ethanol metabolite in adult human body, has been implicated as a biomarker for alcohol consumption and in utero exposure to ethanol. To understand better the physiological relevance of the sulfation of ethanol, it is important to clarify the cytosolic sulfotransferase (SULT) enzymes that are responsible for ethanol sulfation. The present study aimed to identify the major ethanol-sulfating human SULTs and to investigate the sulfation of ethanol under the metabolic setting. A systematic analysis revealed four ethanol-sulfating SULTs, SULT1A1, SULT1A2, SULT1A3, and SULT1C4, among the eleven human SULT enzymes previously prepared and purified. A metabolic labeling study demonstrated the generation and release of ethyl [(35)S]sulfate in a concentration-dependent manner by HepG2 human hepatoma cells labeled with [(35)S]sulfate in the presence of different concentrations of ethanol. Cytosol or S9 fractions of human lung, liver, and small intestine were examined to verify the presence of ethanol-sulfating activity in vivo. Of the three human organs, the small intestine displayed the highest activity.


Asunto(s)
Consumo de Bebidas Alcohólicas/metabolismo , Etanol/metabolismo , Intestino Delgado/enzimología , Hígado/enzimología , Pulmón/enzimología , Sulfotransferasas/metabolismo , Ésteres del Ácido Sulfúrico/metabolismo , Adulto , Biomarcadores/metabolismo , Citosol/metabolismo , Relación Dosis-Respuesta a Droga , Células Hep G2 , Humanos , Coloración y Etiquetado
6.
Med Sci Sports Exerc ; 54(11): 1842-1849, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-36007163

RESUMEN

PURPOSE: Running with increased duty factors (DF) has been shown to effectively reduce external forces during running. In this study, we investigated whether running with increased DF (INCR) also reduces internal musculoskeletal loading measures, defined as peak muscle forces, muscle force impulses, and peak joint contact forces compared with a runners' preferred running pattern (PREF). METHOD: Ten subjects were instructed to run with increased DF at 2.1 m·s -1 . Ground reaction forces and three-dimensional kinematics were simultaneously measured. A musculoskeletal model was used to estimate muscle forces based on a dynamic optimization approach, which in turn were used to calculate muscle force impulses and (resultant and three-dimensional) joint contact forces of the ankle, knee, and hip joint during stance. RESULTS: Runners successfully increased their DF from 40.6% to 49.2% on average. This reduced peak muscle forces of muscles that contribute to support during running, i.e., the ankle plantar flexors (-19%), knee extensors (-18%), and hip extensors (-15%). As a consequence, peak joint contact forces of the ankle, knee, and hip joint reduced in the INCR condition. However, several hip flexors generated higher peak muscle forces near the end of stance. CONCLUSIONS: Running with increased DF lowers internal loading measures related to support during stance. Although some swing-related muscles generated higher forces near the end of stance, running with increased DF can be considered as a preventive strategy to reduce the occurrence of running-related injuries, especially in running populations that are prone to overuse injuries.


Asunto(s)
Carrera , Articulación del Tobillo/fisiología , Fenómenos Biomecánicos , Humanos , Rodilla , Articulación de la Rodilla/fisiología , Músculos , Carrera/fisiología
7.
Contracept X ; 4: 100088, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36419776

RESUMEN

Objective: There has been a growing focus on informed choice in contraceptive research. Because removal of long-acting reversible contraception (LARC), including implants and IUDs, requires a trained provider, ensuring informed choice in the adoption of these methods is imperative. We sought to understand whether information received during contraceptive counseling differed among women using LARC and those using other modern methods of contraception. Study Design: We used cross-sectional data from Burkina Faso, Côte d'Ivoire, the Democratic Republic of Congo (DRC), Kenya, Nigeria, and Uganda collected in 2019-2020 by the Performance Monitoring for Action project. We included 7969 reproductive-aged women who reported use of modern contraception. Our outcome of interest, information received during contraceptive counseling, was measured using a binary indicator of whether respondents answered "yes" to all 4 questions that make up the Method Information Index Plus (MII+). We used modified Poisson models to estimate the prevalence ratio between method type (LARC vs. other modern methods) and the MII+, controlling for individual- and facility-level covariates. Results: Reported receipt of the full MII+ during contraceptive counseling ranged from 21% in the DRC to 51% in Kenya. In all countries, a higher proportion of LARC users received the MII+ compared to other modern method users. A greater proportion of LARC users answered "yes" to all questions that make up the MII+ at the time of counseling compared to other modern method users in DRC, Kenya, Nigeria, and Uganda. There was no significant difference in the prevalence of reporting the full MII+ between users of LARC and other modern methods in Burkina Faso (Adjusted prevalence ratio (aPR): 1.16; 95% confidence interval (CI): 0.91, 1.48) and Côte d'Ivoire (aPR: 1.13; 95% CI: 0.87, 1.45). Conclusion: Information received during contraceptive counseling was limited for all modern contraceptive users. LARC users had significantly higher prevalence of receiving the MII+ compared to other modern method users in the DRC, Kenya, and Uganda. Family planning programs should ensure that all women receive complete, unbiased contraceptive counseling. Implications: Across 6 sub-Saharan African countries, a substantial proportion reproductive-aged women using contraception did not report receiving comprehensive counseling when they received their method. Women using long-acting reversible contraception received more information compared to women using other modern methods in the DRC, Kenya, Nigeria, and Uganda after controlling for individual- and facility-level factors.

8.
BMJ Open Sport Exerc Med ; 7(1): e000996, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33747540

RESUMEN

OBJECTIVES: Recreational runners show a large interindividual variation in spatiotemporal characteristics. This research focused on slow runners and intended: (1) to document the variance in duty factor (DF) between runners in a real-life running setting and (2) examine whether the interindividual variation in DF and stride frequency (SF) relates to differences in external loading parameters between runners. METHODS: Spatiotemporal characteristics of 23 slow runners (ie, <2.6 m/s) were determined during a 5.2 km running event. To relate the interindividual variation in DF and SF to differences in external forces between runners (maximal vertical ground reaction force (FzMax), peak braking force (PBF) and vertical instantaneous loading rate (VILR)), 14 of them were invited to the lab. They ran at 1.9 m/s on a treadmill while ground reaction forces were recorded. A multiple linear regression analysis was conducted to investigate the effect of DF and SF on external force measures. RESULTS: DF between slow runners varied from 42.50% to 56.49% in a recreational running event. DF was found to be a significant predictor of FzMax (R²=0.755) and PBF (R²=0.430). SF only improved the model for PBF, but to a smaller extent than DF (R² change=0.191). For VILR, neither DF nor SF were significant predictors. CONCLUSION: External forces are lower in recreational runners that run with higher DFs and slightly lower SFs. These findings may be important for injury prevention purposes, especially directed to recreational runners that are more prone to overuse injuries.

9.
Cyberpsychol Behav Soc Netw ; 23(1): 34-40, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31692369

RESUMEN

While some evidence-based vocational studies exist for adults with Autism Spectrum Disorder (ASD), most focus on social interaction. This mixed methods exploratory study investigated a multimedia approach to training ASD adults as a strategy for increasing self-efficacy and producing positive training outcomes during the anticipatory socialization and encounter phases of organizational assimilation. Ten ASD adults, seven men and three women, 19 to 42 years of age, participated in the study, which utilized video and virtual reality to instruct participants on how to wire an electrical socket. Significant increases in the participant's self-efficacy were found using a modified version of the New General Self-Efficacy (NGSE) scale. In addition, a thematic analysis of post-training comments showed that participants, overall, were engaged and had fun during the training. These findings suggest that a multimedia approach may be an effective strategy for achieving positive outcomes by increasing self-efficacy and engagement when training newly hired employees diagnosed with ASD to perform vocational tasks.


Asunto(s)
Trastorno del Espectro Autista/terapia , Multimedia , Autoeficacia , Realidad Virtual , Adulto , Femenino , Humanos , Masculino , Adulto Joven
10.
Eur J Sport Sci ; 19(6): 774-783, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30394188

RESUMEN

Purpose. We aimed to determine the effect of speed-induced changes in foot contact patterns on the vertical instantaneous loading rate (VILR). We hypothesized that transition runners, i.e. runners that shift towards a mid- (MF) or forefoot contact pattern (FF) when running speed increases, show smaller increases in VILR than non-transition runners, i.e. runners that remain with a rearfoot contact pattern (RF). Methods. Fifty-two male and female runners ran overground at 3.2, 4.1, 5.1 and 6.2 m s-1. Ground reaction forces, lower limb sagittal plane knee and ankle kinematics and plantar pressures were recorded. Multi-level linear regression models were used to assess differences between transition and non-transition runners. Results. Non-transition runners experienced larger speed-induced increases in VILR (48.6 ± 2.6 BW s-1 per m s-1) than transition runners (-1.4 ± 7.6 BW s-1 per m s-1). Transition runners showed higher VILRs and a more flat foot touch down at the same pre-transition speed than non-transition runners. Conclusion. When running speed increases, some runners transition towards more anterior foot contact patterns. This reduces or even eliminates the speed-induced increase in VILR. This result is especially the case for those RF runners who already have relatively high VILRs and flat foot positioning at slower running speeds.


Asunto(s)
Pie/fisiología , Marcha , Carrera/fisiología , Adulto , Articulación del Tobillo , Fenómenos Biomecánicos , Femenino , Humanos , Articulación de la Rodilla , Masculino , Presión , Adulto Joven
11.
Med Sci Sports Exerc ; 51(4): 708-715, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30480615

RESUMEN

PURPOSE: Recent observations demonstrate that a sizeable proportion of the recreational running population runs at rather slow speeds and does not always show a clear flight phase. This study determined the key biomechanical and physiological characteristics of this running pattern, i.e., grounded running (GR), and compared these characteristics with slow aerial running (SAR) and reference data on walking at the same slow running speed. METHODS: Thirty male subjects performed instructed GR and SAR at 2.10 m·s on a treadmill. Ground reaction forces, tibial accelerations, and metabolic rate were measured to estimate general musculoskeletal loading (external power and maximal vertical ground reaction force), impact intensity (vertical instantaneous loading rate and tibial acceleration), and energy expenditure. More explicit measures of muscular loading (muscle stresses and peak eccentric power) were calculated based on a representative subsample, in which detailed kinematics and kinetics were recorded. We hypothesized that all measures would be lower for the GR condition. RESULTS: Subjects successfully altered their running pattern upon a simple instruction toward a GR pattern by increasing their duty factor from 41.5% to 51.2%. As hypothesized, impact intensity, general measures for musculoskeletal, and the more explicit measures for muscular loading decreased by up to 35.0%, 20.3%, and 34.0%, respectively, compared with SAR. Contrary to our hypothesis, metabolic rate showed an increase of 4.8%. CONCLUSIONS: Changing running style from SAR to GR reduces musculoskeletal loading without lowering the metabolic energy requirements. As such, GR might be beneficial for most runners as it has the potential to reduce the risk of running-related injuries while remaining a moderate to vigorous form of physical activity, contributing to fulfillment of the recommendations concerning physical activity and public health.


Asunto(s)
Marcha/fisiología , Fenómenos Fisiológicos Musculoesqueléticos , Carrera/fisiología , Aceleración , Fenómenos Biomecánicos , Metabolismo Energético , Humanos , Masculino , Factores de Riesgo , Carrera/lesiones , Estrés Mecánico , Tibia/fisiología
12.
Med Sci Sports Exerc ; 46(8): 1595-603, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24504424

RESUMEN

PURPOSE: This study assessed initial foot contact patterns (IFCP) in a large group of distance runners and the effect of speed on the IFCP. METHODS: We determined the strike index to classify the runners in IFCP groups, at four speeds (3.2, 4.1, 5.1, and 6.2 m·s), by measuring center of pressure (COP) with a 2-m plantar pressure plate. Such a system allows a direct localization of the COP on the plantar footprint and has a low threshold value (2.7 N·cm), resulting in more accurate COP data at low ground reaction forces than when obtained from force plate. RESULTS: The IFCP distribution evolves from mostly initial rearfoot contact (IRFC) (82%) at 3.2 m·s to more anterior foot contacts with an approximately equal distribution of IRFC (46%) and initial midfoot or forefoot contact (54%) at 6.2 m·s. Approximately 44% of the IRFC runners showed atypical COP patterns with a fast anterior displacement of the COP along the lateral shoe margin. Apart from the different COP patterns, these atypical IRFC were also characterized by a significantly higher instantaneous vertical loading rate than the typical IRFC patterns. CONCLUSIONS: The IFCP distribution changes were due to intraindividual alterations in IFCP at higher speeds. That is, 45% of the runners made one or even two "transitions" toward a more anterior IFCP (and 3% shows some other type of transition between initial foot contact styles as speed increases). However, 52% of the runners remained with the same IFCP.


Asunto(s)
Pie/fisiología , Marcha/fisiología , Carrera/fisiología , Adulto , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Presión , Zapatos , Adulto Joven
13.
J Appl Biomech ; 22(1): 33-40, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16760565

RESUMEN

Seven top amateur or professional skateboarders (BW=713 N+/-83 N) performed Ollie maneuvers onto and off an elevated wooden platform (45.7 cm high). We recorded ground reaction force (GRF) data for three Ollie Up (OU) and Ollie Down (OD) trials per participant. The vertical GRF (VGRF) during the OU has a characteristic propulsive peak (M=2.22 body weight [BW]+/-0.22) resulting from rapidly rotating the tail of the board into the ground to propel the skater and board up and forward. The anterior-posterior (A-P) GRF also shows a pronounced peak (M=0.05+/-0.01 BW) corresponding with this propulsive VGRF peak. The initial phase of landing in the OD shows an impact peak in VGRF rising during the first 30 to 80 ms to a mean of 4.74+/-0.46 BW. These impact peaks are higher than expected given the relatively short drop of 45.7 cm and crouched body position. But we observed that our participants intentionally affected a firm landing to stabilize the landing position; and the Ollie off the platform raised the center of mass, also contributing to higher forces.


Asunto(s)
Fenómenos Biomecánicos , Pie/fisiología , Movimiento/fisiología , Patinación/fisiología , Adulto , Humanos , Cinética , Masculino , Postura/fisiología , Estrés Mecánico , Soporte de Peso/fisiología
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