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BACKGROUND: When one thinks of jobs with physical employment standards, the first thoughts typically center around firefighting, law enforcement, and military jobs. However, there are 100s of arduous jobs that exist in the public and private sectors that range from moderately demanding to strenuous. The Bureau of Labor Statistics reported that 28% of the workforce in the United States performs physically demanding jobs that involve construction, machinery installation and repair, public safety, and other professions. OBJECTIVE: This paper provides a historical perspective of physical employment standards for hiring workers into these arduous jobs, how we arrived at our current knowledge base, and the challenges faced today when determining and implementing physical employment standards. METHOD: This narrative review draws on evidence from 62 published sources. RESULTS: This paper focuses on the need for a multidisciplinary approach to identifying job requirements, the professions (e.g., medical, psychology, physiology) that underpin the methodologies, and the knowledge used by current researchers. Descriptions of test and cut score development, legal issues, and challenges for the future also are highlighted. [ABSTRACT FROM AUTHOR]

Variable stiffness actuator is a new actuation of robot which is inspired by motor control of human arm. And it is promising way to exploit the human-like performance and human-like motion. However, due to the mechanical complexity and redundancy of the actuators, it is not trivial to control the variable stiffness actuated robot to perform a human-like motion. In this paper, the weight lifting problem with variable stiffness actuated robot is studied. Then, the original problem is formulated as a constrained optimal control problem and transformed as a general nonlinear programming problem with Gauss pseudospectral method. Simulation studies demonstrate the effectiveness of the proposed method compared with the iLQR approach. Furthermore, the simulations results are presented to show the influence of stiffness variation of variable stiffness actuators on the weight lifting problem. [ABSTRACT FROM AUTHOR]

Traction systems are a good choice for high-rise lift systems, especially in deep wells. With increasing lift depth and weight, rope-guided traction systems have become an essential design methodology in the mine lift field. In this paper, a comprehensive mathematical model is established to simulate the dynamical responses of a rope-guided traction system with different terminal tensions acting on the compensating rope. The results and analysis presented in this paper reveal dynamical responses in terms of longitudinal and transverse vibration. Additionally, a wide range of resonances occurs in the target system. Differences in the dynamical responses between a traditional traction system and tensioned traction system are analysed in detail. Through comparison and analysis, it is determined that terminal tension plays an important role in the suppression of longitudinal vibration in a system. However, changes in the amplitude of longitudinal vibration are independent of terminal tension, which only affects longitudinal elastic elongation and does not affect the basic shape of longitudinal and transverse vibrations. Based on this analysis, it can be concluded that longitudinal vibration suppression can be achieved by applying proper tension on the compensating rope to ensure that it reaches a tensioning state. Continuing to increase terminal tension is not beneficial for the vibration suppression of a system. The results presented in this paper will serve as a valuable guide for the design and optimisation of traction systems. [ABSTRACT FROM AUTHOR]

Athletes are under the utmost pressure to reach excellence in their performance and achieve the desired outcomes in competitions, prompting them to use dietary supplements. Given the threats to both health and eligibility, it is crucial to observe the prevalence, sources of information, knowledge, attitudes, and practices (KAPs) among Lebanese athletes practicing their sports for at least two years. In the present paper, a cross-sectional study is performed using the snowball sampling method, in which a self-administered KAP questionnaire is used to collect data from 455 athletes (mean age: 27.4 ± 7.9 years; men: 73.1%) participating in four sports categories (ball games, combat sports, endurance sports, and weightlifting). Among the Lebanese athletes, the prevalence of dietary supplement (DS) use was 74%, where half of them had predominately used sports supplements. Athletes in Lebanon heavily rely on coaches (74%) and online sources, including webpages and social media (64%), as key information sources for DSs. The findings suggest that significant proportions of athletes show knowledge deficits and unsatisfactory attitudes towards multiple aspects related to supplementation. Moreover, education and sports type modulate the use of DSs among athletes. Furthermore, 34% reported using supplements without a recommendation from specialists, and 69% admitted to not reading the supplement's nutrition facts. This study urges the need for the regulation of concerned authorities and education programs to help overcome the existing challenges. [ABSTRACT FROM AUTHOR]

This research introduces an optimal Fin Ray gripper design for vegetable handling in horticulture applications. Fin Ray grippers are triangular with crossbeams. The gripper flexes and adjusts to the structure of the object upon activation. The change in the gripper's form resembles fish fin physiology. This research entails the design and fabrication of Fin Ray inclined grippers with variations in their geometrical structure, namely, the gap between the crossbeams, the inclination angle of the crossbeams, and the thickness of the crossbeams. The Box-Behnken design and analysis of variance approaches were used to assess the major impacts, interactions, and importance of the crossbeam's characteristics on weightlifting capacity and displacement. The Fin Ray gripper design parameters were successfully optimised by the chosen Response Surface Methodology. Less force is needed to obtain a good grasp on an object when a design is made to achieve optimum weightlifting capacity and bending displacement. The gripper's design and analysis, as well as the experimental results demonstrating how well it handles various types of vegetables, are described in the paper. The design of an optimal Fin Ray gripper presents a new and unique idea for adaptive grasping in horticultural robots. [ABSTRACT FROM AUTHOR]

A folding wing aircraft can autonomously change its configuration in flight to respond to different flying environments. Hinge moment during morphing process is an important basis for driving mechanism design and structural strength check, and its calculation depends on the simulation of the morphing process. Existing studies mostly use the simplified lifting surface method for aerodynamic modeling. In this paper, the CFD-based simulation method is studied, and the results are compared with those by the lifting surface method. First, the unsteady aerodynamic modeling method of the folding wing based on the CFD method is studied, an effective description method is given to define the wall mesh motion caused by wing folding and aileron deflection, and an unfolding–refolding strategy is proposed to improve the quality of the internal mesh in the case of large folding angles. Then, the CFD aerodynamic model is coupled through a developed coupling calculation program with the flexible multibody structure model for the simulation of a flight-morphing process. The comparison with the results of the lifting surface method shows that hinge moments obtained according to the two aerodynamic models are markedly different. Analysis of the difference shows that airfoil thickness considerably affects aerodynamic loading distributions and hinge moments of folding wing aircraft. The lifting surface method ignores airfoil thickness, which will cause large simulation errors in hinge moments. [ABSTRACT FROM AUTHOR]

Velocity-based training is a contemporary method used by sports coaches to prescribe the optimal loading based on the velocity of movement of a load lifted. The most employed and accurate instruments to monitor velocity are linear position transducers. Alternatively, smartphone apps compute mean velocity after each execution by manual on-screen digitizing, introducing human error. In this paper, a video-based instrument delivering unattended, real-time measures of barbell velocity with a smartphone high-speed camera has been developed. A custom image-processing algorithm allows for the detection of reference points of a multipower machine to autocalibrate and automatically track barbell markers to give real-time kinematic-derived parameters. Validity and reliability were studied by comparing the simultaneous measurement of 160 repetitions of back squat lifts executed by 20 athletes with the proposed instrument and a validated linear position transducer, used as a criterion. The video system produced practically identical range, velocity, force, and power outcomes to the criterion with low and proportional systematic bias and random errors. Our results suggest that the developed video system is a valid, reliable, and trustworthy instrument for measuring velocity and derived variables accurately with practical implications for use by coaches and practitioners.

In this paper presents the technical state in which it is found in which is the mechanism of lifting ladder from the coal extraction machine, following technical expertise. Rehabilitation to which the lifting mechanism will be subjected of the ladder will be done through the execution of the intervention works which will return to normal operating parameters both the structural part and the functional part. In the work paper are presented: verification procedures of the mechanism as well as the technical solutions proposed to repair the mechanism. [ABSTRACT FROM AUTHOR]

Stay-at-home orders and shutdowns of non-essential businesses are powerful, but socially costly, tools to control the pandemic spread of SARS-CoV-2. Mass testing strategies, which rely on widely administered frequent and rapid diagnostics to identify and isolate infected individuals, could be a potentially less disruptive management strategy, particularly where vaccine access is limited. In this paper, we assess the extent to which mass testing and isolation strategies can reduce reliance on socially costly non-pharmaceutical interventions, such as distancing and shutdowns. We develop a multi-compartmental model of SARS-CoV-2 transmission incorporating both preventative non-pharmaceutical interventions (NPIs) and testing and isolation to evaluate their combined effect on public health outcomes. Our model is designed to be a policy-guiding tool that captures important realities of the testing system, including constraints on test administration and non-random testing allocation. We show how strategic changes in the characteristics of the testing system, including test administration, test delays, and test sensitivity, can reduce reliance on preventative NPIs without compromising public health outcomes in the future. The lowest NPI levels are possible only when many tests are administered and test delays are short, given limited immunity in the population. Reducing reliance on NPIs is highly dependent on the ability of a testing program to identify and isolate unreported, asymptomatic infections. Changes in NPIs, including the intensity of lockdowns and stay at home orders, should be coordinated with increases in testing to ensure epidemic control; otherwise small additional lifting of these NPIs can lead to dramatic increases in infections, hospitalizations and deaths. Importantly, our results can be used to guide ramp-up of testing capacity in outbreak settings, allow for the flexible design of combined interventions based on social context, and inform future cost-benefit analyses to identify efficient pandemic management strategies. Author summary: The global spread of SARS-CoV-2 and the strategies used to manage it have come at significant societal costs. We analyze how mixed control strategies, which utilize interventions that prevent new infections from occurring (e.g., distancing or shut-downs) and others that actively search for and isolate existing infections (here, mass testing), can achieve improved public health outcomes while avoiding severe socio-economic burdens. Our results suggest that increasing testing capacity, including the number of tests available and the speed at which test results are provided, can reduce reliance on costly preventative interventions. Such reduction is possible with more isolation of active infections, including those without reported symptoms. However, failing to maintain preventative interventions without sufficient testing capacity can lead to large increases in infection burdens. By defining the combined effect of these interventions through mathematical models, this study provides insight into relaxation of distancing measures, and lays the groundwork for future public health economics analyses on the cost-effectiveness of combined management strategies. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to preparing exercises of constant intensity in developing muscle strength for lifters in Clean and jerk by lifting weights for young people, and the researcher used the experimental method with the pre and post-test for the experimental and control groups. The research sample was conducted in a comprehensive inventory method, and the sample was divided into two groups, the experimental group and the control group, with (6) quarters for each group. In addition, researcher used the SPSS statistical bag to process the data and get the results, including the researcher reached the most important conclusion that frequent intensity exercises have a positive impact on developing muscle strength for lifters in Clean and Jerk by lifting weights for young. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the influence of certain morphological characteristics on the expression of static strength in bodybuilders and weightlifters. The sample of respondents in this research is made up of athletes (N = 61) who are actively engaged in bodily building and weight lifting, members of U.G. Fitness club "GYM" in Banovići. The choice of variables was carried out in accordance with the problems encountered in this research, based on which the relevant indicators of the relationships and the influence of the investigated anthropological features - morphology in the expression of static strength in the respondents can be reached. The choice of variables is based on past experience and research of similar issues. The area of morphological characteristics is represented by nine variables according to the International Biological Program (IBP): 1. Body height (ATJVIS), 2. Leg length (ADULT), 3.Arm length (ADDRESS), 4.Breast circumference (AOBGRU), 5.The volume of the abdomen (AOBTRB), 6.The circumference of the upper arm (AOBNAD), 7.The circumference of the forearm (AOBPOD), 8.The circumference of the thigh (AOBNAT), 9.The circumference of the lower leg (AOBPOT). The variables are structured from the longitudinal dimensionality of the skeleton and body circumference as variables subject to transformation under the influence of different operators and responsible for the manifestation of different types of strength. For the research of strength as a segment of the motor space, tests that were used reflect the apparent dimensions of static power and make it two variables: 1. Semi-tongue discharge (SSIPCU), 2. Tumble hold (SSIZGI). The results show that the morphological characteristics have 24% influence on the expression of the static strength of the lower extremities. Individually, the greatest influence on the manifestation of static foot strength was achieved by the variables of the circumference of the hip, the volume of the abdomen and the volume of the breast. We can conclude that subjects with higher circumference and breast, and without adipose tissue of the abdomen, had higher static strength of lower extremities than subjects who do not possess such morphological characteristics. The researched variables of morphological characteristics in this paper participate in the prediction of the static power of the upper extremities with 63% impact. On the isolated predictive function, the dominant role is played by the variables of the body height and length of the arm, and the volume of the abdomen. All three measures are a negative sign, meaning that subjects with these characteristics had lower static strength of the upper extremities, while subjects with lower body height and volume of the abdomen and shorter upper extremities manifested greater static strength of the arm. [ABSTRACT FROM AUTHOR]

This paper presents the effect of the local low-pressure region in the atmosphere and rain on aerodynamic characteristics of medium altitude long endurance unmanned aerial vehicle (MALE-UAV) configuration during cruise/loiter. Computations are performed using CFD++, a commercial CFD software suite. A large low-pressure depression past the MALE UAV (symmetrically and asymmetrically) with pressure 10 - 15 % lower than the free stream pressure and a widespread rainfall type with a rainfall rate of 1195 mm/hr., are considered for CFD simulation. A large low pressure that spans the whole MALE-UAV results in a decrement in both lift and drag, but does not affect the yawing and rolling moments significantly. However, a low-pressure region that engulfs only one-half of MALE UAV causes sudden/abrupt changes in rolling and yawing moments. The effect of rain causes a significant decrease in a lift at higher alpha, accompanied by a decrease in stall angle of 2 degrees, and a significant increase in drag. From the study, a Standard Operating Procedure (SOP) was adopted to fly UAVs in adverse weather effects, such that the aircraft can be operated with a velocity higher than 1.3Vstall and at a power setting not less than 75% of max power capacity. [ABSTRACT FROM AUTHOR]

Feature selection is of great importance in the world of data mining. The existing algorithms for doing so lead to extremely high dimensionality when interactions among features are considered. So, an algorithm is needed to extract only useful features. An Improvised approach for association rule mining is devised, which does not require the users to provide support and confidence values and we are considering the interaction among features and relative confidence to get the better result. The user can specify the number of rules and features that have to be generated. This method has an advantage over Standard Apriori, as it gives more control over the efficiency and quality of the results. It is also capable to handle large data sets and high dimensions more effectively. We calculated mean, median, variance and standard deviation on the lift value of rules generated and found that variance of improvised apriori is 30 - 40% lower than that of standard apriori, which indicates that modified Apriori performs better than standard apriori. The mean and median value of the lift is also 20 - 50% higher in modified apriori than in standard apriori, which implies that the features are more tightly coupled in modified apriori than in standard apriori and hence have a higher probability of getting the perfect result. [ABSTRACT FROM AUTHOR]

Humans are excellent at perceiving different features of the actions performed by others. For instance, by viewing someone else manipulating an unknown object, one can infer its weight-an intrinsic feature otherwise not directly accessible through vision. How such perceptual skill develops during childhood remains unclear. To confront this gap, the current study had children (N:63, 6-10 years old) and adults (N:21) judge the weight of objects after observing videos of an actor lifting them. Although 6-year-olds could already discriminate different weights, judgment accuracy had not reached adult-like levels by 10 years of age. Additionally, children's stature was a more reliable predictor of their ability to read others' actions than was their chronological age. This paper discusses the results in light of a potential link between motor development and action perception., Competing Interests: The authors have declared that no competing interests exist.

This paper presents an aerial manipulation robot consisting of a hexa-rotor equipped with a 2-DOF (degree of freedom) Cartesian base (XY–axes) that supports a 1-DOF compliant joint arm that integrates a gripper and an elastic linear force sensor. The proposed kinematic configuration improves the positioning accuracy of the end effector with respect to robotic arms with revolute joints, where each coordinate of the Cartesian position depends on all the joint angles. The Cartesian base reduces the inertia of the manipulator and the energy consumption since it does not need to lift its own weight. Consequently, the required torque is lower and, thus, the weight of the actuators. The linear and angular deflection sensors of the arm allow the estimation, monitoring and control of the interaction wrenches exerted in two axes (XZ) at the end effector. The kinematic and dynamic models are derived and compared with respect to a revolute-joint arm, proposing a force-position control scheme for the aerial robot. A battery counterweight mechanism is also incorporated in the X–axis linear guide to partially compensate for the motion of the manipulator. Experimental results indoors and outdoors show the performance of the robot, including object grasping and retrieval, contact force control, and force monitoring in grabbing situations. [ABSTRACT FROM AUTHOR]

Purpose: Heavy industrial construction often relies on large mobile cranes to erect equipment and pre-assembled modules. Engineering calculations are required for the lifting analysis where lifting capacity is analyzed to ensure the feasibility of the lifting scenarios. Such engineering calculations are often presented in static formats, e.g. two-dimensional or three-dimensional models. However, it is difficult to help practitioners (e.g. lifting engineers, site crews and operators) understand the complexity of the lifting process and thus operational decisions are often made intuitively. Therefore, this paper aims to introduce a game-based simulation system to allow for interactive analysis of the lifting process to improve lifting efficiency and safety. Design/methodology/approach: The proposed method treats the mobile crane as a robot with degree-of-freedoms, and the movements are simulated in the Unity game environment. The lifting capacity is calculated dynamically based on the lifting object weight, rigging weight and lifting radius. Findings: Compared with the four-dimensional visualization, this development has added a dimension of real-time interactive simulation; this allows the users to understand the complexity and feasibility of the lifting process. Originality/value: The developed prototype has been tested and validated using a real case study from a heavy industrial project with the possibility of generalizing crane lifting configurations. [ABSTRACT FROM AUTHOR]

Use of high performance fibre ropes (HPFR) is attractive in subsea operations due to high strength and low weight making lifting operations in deep waters possible with practically no reduced lifting capacity. However, experiments show that HPFRs can cause higher loads on multilayer winch drums compared to steel wire ropes. This paper presents comparisons between experimental stress measurements and calculation methods for a steel wire and two different HPFRs, wound in 10–14 layers at different rope tensions. The results show that the tangential stresses in the drum are reasonably assessed for the steel wire and a dimensionally stable HPFR, but considerably underestimated for a more deformable HPFR with more than 3–7 layers of rope, dependent on rope tension. The results also show that the method specified by class-societies is not capable of calculating relevant tangential stress in multilayer winch drums with HPFRs. [ABSTRACT FROM AUTHOR]

Lumbar Exoskeleton, as an important instance of wearable exoskeleton, has broad application prospects in logistics, construction, and other industries. Specifically, in the working scenarios that require long-term and repeated bending and rising movements, active lumbar exoskeleton (ALE) can provide effective protection and flexible assistance to wear's waist muscles and bones, which will significantly reduce the risk of lumbar muscle strain. How to improve the human-machine coupling and enhance the assistance performance are the main challenges for ALE's development. Based on the biomechanical analysis of the movement of lifting heavy objects from bottom up, this paper proposes a lightweight but powerful ALE, named as SIAT-WEXv2, which can output maximum assistive force of 28 N. Additionally, we use robust fuzzy adaptive algorithm to improve SIAT-WEXv2's antidisturbance ability, so that it can provide continuous and supple assistance for wearer. Electromyography (EMG) signals of the lumbar erector spinae (LES) from ten subjects in two experimental cases (with or without SIAT-WEXv2) were collected to evaluate the effectiveness of our new ALE. The experimental results indicate that the reduction of iEMG signal at LES decreased monotonically from 60% ± 5.5% to 40.5% ± 6.5% as the weight of lifting load increased from 0 to 25 kg. [ABSTRACT FROM AUTHOR]

In this paper, I have analyzed The Heart Divided by Mumtaz Shah Nawaz through the postcolonial lens to trace the trajectory of the resistance of Muslim woman in the public sphere. The story revolves around three female characters Zohra, Sughra (the siblings) and a Hindu girl Mohni. The domestic space in Muslim household is divided into Zenana( the space specified for women ) and Mardana ( the space for men). Muslim women cannot cross this border line in the practice of daily life. And if ever, they go out, they have to veil their faces. My argument is that through the removal of the veil, Shah Nawaz explores the possibility of the participation of Muslim women in the public sphere. The trope of marriage serves as the site of contestation between the traditional Muslim patriarchal demands and the feminine desire to subvert it. Sughra, in the beginning of the novel, cherishes the ideals of a traditional Muslim woman who finds fulfillment through marriage. But the experience of a loveless marriage changes her views regarding the traditional gender roles in Muslim family structure. As an estranged wife, she finds refuge in the political struggle of the Muslim League. Zohra also refuses to accept the proposal of an arranged marriage. The veil is lifted both in the literal and metaphorical sense. Both the sisters are agreed to resist the patriarchal demands of conformity and decide to participate in the public sphere. Thus, the lifting of veil becomes symbolic of feminist resistance against patriarchal oppression which insists on confining women only to the private sphere of their lives. [ABSTRACT FROM AUTHOR]

The primary purpose of this paper was to provide insight into the effect of different training methods on sprinting time in male youth aged 8-18 years. Specific and nonspecific training methods were identified, the participants of the fiveteen studies chategorized into pre, mid- and postpeak height velocity and effect sizes and percent changes calculated for each training method were appropriate. Plyometric training had the most effect on sprint times in pre- and midpeak height velocity participants, while combined training methods were the most efficient in postpeak height velocity participants. However, it is difficult to quantify the effects of different training methods due to the limited knowledge in this area e.g., resisted training on pre-PHV participants. Furthermore, it may be worthwhile to investigate additional variables (i.e., stride length, stride frequency, horizontal force), to better determine effect of training methods in different maturity statuses, the development of sprinting and possible stages where individual development can be optimized by training. [ABSTRACT FROM AUTHOR]

This paper gives an account of the social forces exerted to contain women’s interest and access to weightlifting, and a muscular strength usually associated with masculinity. Weightlifting can create formidable physical strength but without the visible, physical displays of body building. The significance of weightlifting women’s lack of visibility is important and alters the social dynamic of their experience of physical strength. The study relies on in-depth, semi-structured interviews with 16 elite women weightlifters. They recount how disciplined, different and empowered they perceive themselves to be. Drawing together the weightlifting women’s illuminative epiphanic moments (,,) revealed the close association of strength with force and, the social expectation that, not only is powerful physicality used to dominate others, but it is also expected to be male. Women’s access to domination is contained through the gendered nature of gym space and a masculine approach to training. Strength training is not only a source of selfidentity, but it is also a site of collective experience and enforced norms of affective behaviour. The paper concludes that it is important for women to be supported in their challenge in this arena. [ABSTRACT FROM AUTHOR]

Background: Understanding postural control in low back pain (LBP) subgroups can help develop targeted interventions to improve postural control. The studies on this topic are limited. Therefore, the primary purpose of this study was to compare the postural control of LBP subgroups with healthy individuals during overhead load lifting and lowering. Methods: In this cross-sectional study, the participants were 52 with LBP and 20 healthy. The LBP patients were classified based on the O'Sullivan classification system into 21 flexion patterns and 31 active extension patterns. The participants lifted the box from their waists to their overheads and lowered it to their waists. Changes in postural control parameters were measured with a force plate system. Results: The results of the analysis of variance showed that during load lifting, the mediolateral phase plane (p =.044) and the mean total velocity (p =.029) had significant differences between flexion patterns and healthy. Also, the load-lowering results showed that active extension patterns, compared with healthy, had significant differences in the anteroposterior–mediolateral phase plane (p =.042). The patients showed less postural sway than the healthy. Conclusions: The results in this work highlight the importance of identifying the homogenous subgroups in LBP and support the classification of heterogeneous LBP. Different subgroups exhibit different postural control behaviors. These behaviors can be due to the loading of various tissues during different tasks. [ABSTRACT FROM AUTHOR]

Most people with intellectual disabilities have comorbid health conditions, which will impact optimization of sporting performance. Classification is used in Paralympic events to ensure that those with similar levels of functional ability compete fairly against each other. An evidence-based approach needs to be developed for athletes with intellectual disabilities to be classified in relation to their overall functional capacity into competition groups of similar ability. This research builds on previous work using the taxonomy of The International Classification of Functioning, Disability and Health (ICF) to group athletes with intellectual disabilities into comparable competition groups as an approach to Paralympic classification. Three groups of athletes—Virtus, Special Olympics, and Down syndrome—are compared using the ICF questionnaire indicating functional health status in relation to sporting performance. The questionnaire was found to discriminate between athletes with Down syndrome and other athletes, and an approach to using a cutoff score to develop competition classes is explored. [ABSTRACT FROM AUTHOR]

Purpose: This study investigated the evolution of neuromotor control during a typical short sport-specific rehabilitation program (SSR) in professional soccer players who had incurred a major lower-limb injury (n = 15, chondral and muscle injuries, ACL-reconstruction). Methods: All injured participants (n = 15) were in the on-field rehabilitation phase of their specific sport rehabilitation process, prior to return to play. An experimental group (EG, chondral and muscle injuries, ACL-reconstruction) followed a 3-week SSR-program composed of muscular and core strengthening (weightlifting, functional stability, explosivity and mobility exercises), running and cycling, neuromotor reprogramming, cognitive development and specific soccer on-field rehabilitation (acceleration, braking, cutting, dual-contact, high-speed-running, sprint, jump, drills with ball). Neuromotor control via analysis of movement kinematics, muscle activation and kinetic parameters was evaluated using a single-leg Countermovement-Jump, pre- and post- rehabilitation program. A control group (n = 22) of healthy soccer players of similar standards performed the same single-leg Countermovement-Jump to provide reference values regarding the level to be attained by the injured players for return to play. Results: In the experimental group, almost all kinetic analyses values progressed during the program and significantly for concentric Rate-of-Force-Development (p < 0.05), height jump (p < 0.001) and Reactive-Strength-Index Modified (p < 0.001) but remained lower than control group values for RSI-Mod (p < 0.05) and RFDconcentricLate (p < 0.001). Activation changed (p < 0.05) for all muscles except for rectus femoris and medial gastrocnemius in the pushing phase and rectus femoris during landing in the EG. Activation of all muscles decreased for EG, except for semitendinous which increased. Regarding kinematic analyses during the landing phase, there were a significant decrease in peak trunk flexion (p < 0.001) and lateroflexion (p < 0.001) and an increase in peak knee flexion (p < 0.001) for both legs. Trunk flexion (p < 0.001) and lateroflexion (p < 0.001) values were again higher for EG while knee flexion remained significantly lower than the CG (p < 0.001). Conclusion: The SSR generally improved neuromotor control suggesting that the present specific sport rehabilitation program, albeit of only three weeks duration, was effective in aiding elite footballers recover their neuromotor qualities although this was potentially insufficient to return to the values observed in healthy players. [ABSTRACT FROM AUTHOR]

Copyright of Retos: Nuevas Perspectivas de Educación Física, Deporte y Recreación is the property of Federacion Espanola de Asociaciones de Docentes de Educacion Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: The movement of the barbell has been detected as success factor for the snatch and the clean and jerk events. As the barbell's movement has been shown to be related to the athlete's body movement, we hypothesized that the latter could be a success factor also for the back squat (BS) event. Hence, this study aimed to investigate postural control during the execution of the BS at different load intensities in powerlifters and weightlifters. Methods: Seventeen powerlifters and weightlifters were enrolled and the one-repetition maximum (1-RM) of the BS of each participant was measured. Afterwards, the assessment of postural control during the execution of the BS at different load intensities (i.e. 60%, 70%, 80%, 90%, 100%) of the 1-RM of each participant was carried out through a posturographic platform to measure the displacement of the centre of pressure (CoP). The following parameters were considered: sway path length (SPL), sway ellipse surface (SES), length/surface (LFS ratio), sway mean speed (SMS), CoP coordinates along X and Y planes. Results: We found a significant increase in SPL and LFS ratio, and a significant decrease in SMS as the load intensity increased. In detail, we detected a significant difference in: (a) SPL between the BS at 60% and 80%, 60% and 90%, 60% and 100%; between the BS at 70% and 90%, 70% and 100%; between the BS at 80% and 100%; and between the BS at 90% and 100%; (b) SMS between the BS at 60% and 80%, 60% and 90%; (c) LFS ratio between the BS at 60% and 90%, 60% and 100%. Conclusions: These results suggest that powerlifters and weightlifters adopt different postural control strategies depending on the load intensity when performing the BS. Our findings showed that higher effort could affect postural control during the BS. Thus, postural control could be considered a success factor for the BS. [ABSTRACT FROM AUTHOR]

Copyright of Collegium Antropologicum is the property of Croatian Anthropological Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The present work combines ergonomics with the posture prediction in the assembly process to avoid musculoskeletal issues of human operator. For improved productivity the operator should be in a better work environment and in sound health. The purpose of this paper is to provide a different perspective to avoid ergonomic risk factors in manual assembly. Here, a human is modeled as 20-DOF as modeled in robotic analysis and simulated in a virtual environment. In the present study, two objective cost functions i.e. joint discomfort function and energy expenditure function have been employed for evaluating the optimized posture. For posture prediction, a combined multi-objective optimization (MOO) method is used and the objective cost functions are minimized i.e. less joint discomfort and less energy in MOO method required to do the manual assembly operation and consequently, the results are compared and finally the movements are tested using REBA technique. [ABSTRACT FROM AUTHOR]

Decommissioning of offshore platforms is becoming increasingly popular. The removal of these heavy steel structures is characterised by high risks that may compromise personnel safety and loss of assets. The removal operation relies on dedicated barges and heavy lift vessels that may descent or capsize because of mechanical or structural failure. The knowledge of associated hazards is driven by experience and failure data are often obtained empirically through analogous operations, which further introduces uncertainty to the risk analysis. This paper proposes an integrated safety analysis approach for conducting a decommissioning risk analysis of offshore installations. The approach incorporates hierarchical Bayesian analysis (HBA) with Bayesian network (BN) to assess the accident causations leading to futile decommissioning operation. First, the overall system failure of a lifting vessel was reviewed with an emphasis on where safety issues arise. In addition, the failure data obtained from expert judgements were aggregated through statistical distribution based on HBA. The aggregated failure data are then used to conduct dynamic safety analysis using BN, to assess and evaluate the risks of offshore jacket removal operations. The accident model is illustrated with a case study from Brent Alpha decommissioning technical document to demonstrate the capability of incorporating HBA with BN to conduct a risk analysis. [ABSTRACT FROM AUTHOR]

Performance enhancing drugs (PEDs) crises in sport provide stories for the mass media. From individuals such as Ben Johnson and Lance Armstrong, to countries and organisations such as Russian Athletics and Major League Baseball. More recently, research has emerged that suggests that those who take drugs, even the once, are permanently advantaged over those who never have (Egner et al., 2013; Eriksson, 2006). This has expanded existing arguments related to PEDs, even extending debate to one that argues that PED use should be monitored and legalised in order to create a level playing field – as opposed to 'banning' athletes. In contrast, there are varying reasons for the rationale of 'clean' sports. In the first kind of discussion related to this the central premise is often about health concerns and PED use. In the second discussion, we hear much about cheating, unfairness, and the perversion of sport (Schneider & Butcher, 2000). At the present time, the World Anti-Doping Agency (WADA) police PED use in sport and use Anti-Doping Rule Violations (ADRVs) that allow a sliding scale of transgressions with lifetime bans not given in the first instance of a failed test. Put simply then, these ADRVs do not facilitate a system for those not wishing to compete with others who, at any time, have used PEDs. However, in the 1980's a number of people in Britain made the decision to distance themselves from what they saw as significant doping in British and international Weightlifting. They achieved this through creating competitive strength organisations dedicated to a drug free for life ethos. In this paper I draw on the experiences and reflections of some of these key people, and contend that it was the ideology of fairplay that influenced this movement, and that the rules on PED use should not be fully authoritative and determinate. [ABSTRACT FROM AUTHOR]

Wave energy has significant worldwide exploitable resource and its exploitation has attracted renewable energy investigator' attention. Great progress on calculating device performance has been made by means of theoretical, numerical and model tests. This paper presents a method of calculating the energy extraction of a wave energy converter (WEC) based on Wave Height Take-off (WHTO). The method provides a means to improve the capture efficiency of designs, including demonstrating how well different kinds of WEC are optimized for certain wave conditions. Numerical simulations of a heaving buoy and a bottom-hinged pendulum in a 2D wave flume with different damping types (linear and nonlinear) are presented. The results show that the difference between the calculated energy extraction from the wave height reduction and from the model power take-off (PTO) was not significant in a 2D flume. Physical model tests were conducted using a simplified PTO consisting of a system of lifting weights, used to measure the energy extraction directly. Based on both numerical and physical model analyses, the article defines WHTO, which is equivalent to energy extracted by PTO, but determined without taking direct measurements. This paper aims to promote and validate the concept of the WHTO. • A methodology of calculating the energy extraction of a WEC by WHTO was promoted. • A numerical model was used to validate the concept of WHTO. • A heaving buoy and a pendulum were applied to find the differences PTO and WHTO. [ABSTRACT FROM AUTHOR]

Context: Research on d-aspartic acid (DAA) has demonstrated increases in total testosterone levels in untrained men, however research in resistance-trained men demonstrated no changes, and reductions in testosterone levels. The long-term consequences of DAA in a resistance trained population are currently unknown., Objective: To evaluate the effectiveness of DAA to alter basal testosterone levels over 3 months of resistance training in resistance-trained men., Design: Randomised, double-blind, placebo controlled trial in healthy resistance-trained men, aged 18-36, had been performing regular resistance training exercise for at least 3 d.w-1 for the previous 2 years. Randomised participants were 22 men (d-aspartic acid n = 11; placebo n = 11) (age, 23.8±4.9 y, training age, 3.2±1.5 y)., Intervention: D-aspartic acid (6 g.d-1, DAA) versus equal-weight, visually-matched placebo (PLA). All participants performed 12 weeks of supervised, periodised resistance training (4 d.w-1), with a program focusing on all muscle groups., Measures: Basal hormones, total testosterone (TT), free testosterone (FT), estradiol (E2), sex-hormone-binding globulin (SHBG) and albumin (ALB); isometric strength; calf muscle cross-sectional area (CSA); calf muscle thickness; quadriceps muscle CSA; quadriceps muscle thickness; evoked V-wave and H-reflexes, were assessed at weeks zero (T1), after six weeks (T2) and after 12 weeks (T3)., Results: No change in basal TT or FT were observed after the intervention. DAA supplementation (n = 10) led to a 16%, 95% CI [-27%, -5%] reduction in E2 from T1-T3 (p<0.01). The placebo group (n = 9) demonstrated improvements in spinal responsiveness (gastrocnemius) at the level of the alpha motoneuron. Both groups exhibited increases in isometric strength of the plantar flexors by 17%, 95% CI [7%, 28%] (p<0.05) as well as similar increases in hypertrophy in the quadriceps and calf muscles., Conclusions: The results of this paper indicate that DAA supplementation is ineffective at changing testosterone levels, or positively affecting training outcomes. Reductions in estradiol and the blunting of peripheral excitability appear unrelated to improvements from resistance training., Trial Registration: Australian New Zealand Clinical Trials Registry ACTRN12617000041358.

Background: Prolonged high-dose anabolic-androgenic steroid (AAS) use has been associated with psychiatric symptoms and cognitive deficits, yet we have almost no knowledge of the long-term consequences of AAS use on the brain. The purpose of this study is to investigate the association between long-term AAS exposure and brain morphometry, including subcortical neuroanatomical volumes and regional cortical thickness., Methods: Male AAS users and weightlifters with no experience with AASs or any other equivalent doping substances underwent structural magnetic resonance imaging scans of the brain. The current paper is based upon high-resolution structural T1-weighted images from 82 current or past AAS users exceeding 1 year of cumulative AAS use and 68 non-AAS-using weightlifters. Images were processed with the FreeSurfer software to compare neuroanatomical volumes and cerebral cortical thickness between the groups., Results: Compared to non-AAS-using weightlifters, the AAS group had thinner cortex in widespread regions and significantly smaller neuroanatomical volumes, including total gray matter, cerebral cortex, and putamen. Both volumetric and thickness effects remained relatively stable across different AAS subsamples comprising various degrees of exposure to AASs and also when excluding participants with previous and current non-AAS drug abuse. The effects could not be explained by differences in verbal IQ, intracranial volume, anxiety/depression, or attention or behavioral problems., Conclusions: This large-scale systematic investigation of AAS use on brain structure shows negative correlations between AAS use and brain volume and cortical thickness. Although the findings are correlational, they may serve to raise concern about the long-term consequences of AAS use on structural features of the brain., (Copyright © 2016 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.)

Since it was first observed, and especially so in recent years, the phenomenon of the so-called "sticking point" in resistance training has attracted a substantial amount of sports and exercise science research. Broadly speaking, the sticking point is understood as the position in the range of motion of a lift at which a disproportionately large increase in the difficulty associated with continuing the lift is experienced. Hence the sticking point is inherently the performance bottleneck, and is also associated with an increased chance of exercise form deterioration or breakdown. Understanding the aspects of lifting performance which should be analysed in order to pinpoint the cause of a specific sticking point and therefore devise an effective training strategy to overcome it is of pervasive importance to strength practitioners, and is conducive to injury avoidance and continued progress. In this paper, we survey a range of physiological and biomechanical mechanisms which contribute to the development of sticking points, and then, led by this insight, review and analyse the findings of the existing observational research on the occurrence of sticking points in three ubiquitous exercises: the bench press, the squat, and the deadlift. The findings of our analysis should be used to inform future research and current resistance training practice.

Purpose Aiming at the unbalancing problem of the neutral equilibrium characteristic for balance hoist in the loading process, the purpose of this paper is to establish a dynamic equation for multi-body using the Lagrange method. It is not difficult to find that the deformation of the boom system has a great influence on the stability of the whole system, through the simulation analysis of the multi-rigid-body system model.Design/methodology/approach Aiming at the unbalancing problem of the neutral equilibrium characteristic for balance hoist in the loading process, the dynamic equation for multi-body is established by Lagrange method. It is not difficult to find that the deformation of the boom system has a great influence on the stability of the whole system, through the simulation analysis of the multi-rigid-body system model.Findings Result shows that different weights have a great influence on the force deformation and vibration of the boom system of balance hoist. With the increase in lifting weight, the force and deformation of the boom system increase; lead to balance hoist unique with characteristics of indifferent equilibrium, proportional amplification, labor-saving operation will be lost, easy to cause the imbalance of balance hoist. Therefore, the appropriate increase in the basic length of the compression bar, reduction in the basic length of the tension rod and the increase stiffness of the boom system can improve the stability of balance hoist, which provides a reference for the optimization and manufacture of the balance hoist structure.Originality/value The simulation model was established by analyzing the working principle and the load condition of the balance hoist, and the simulation and dynamic characteristics of three typical working conditions are analyzed by using ADAMS; result shows that different weights have a great influence on the force deformation and vibration of the boom system of balance hoist. With the increase in lifting weight, the force and deformation of a boom system increase, lead to balance hoist unique with characteristics of indifferent equilibrium, proportional amplification, labor-saving operation will be lost, easy to cause the imbalance of balance hoist. [ABSTRACT FROM AUTHOR]

This paper presents the design process and experimental results of a brand new flapping and trailing edge control mechanism for a flapping wing micro air vehicle. The flapping mechanism, whose main components are fabricated from string, is suggested and optimized further by a modified pattern search method. The trailing edge control mechanisms for pitching and rolling moments are designed to be attached onto the present flapping mechanism in a modularized fashion. Prototypes of both mechanisms are fabricated and experimentally tested in order to examine the feasibility of the designs. It is expected that the present flapping mechanism will generate enough lift for the total weight of the vehicle. The present control mechanism is found to be able to supply sufficient control moment. [ABSTRACT FROM AUTHOR]

Purpose: Considerable debate exists as to whether increases in strength that occur with resistance exercise are the result of increases in muscle size. Most studies have attempted to answer this question using assessments of whole muscle size and voluntary muscle strength, but examining changes at the individual muscle fiber level may also provide some insight. The purpose of this meta-analysis was to compare adaptations at the whole muscle and individual fiber level.Methods: A meta-analysis was conducted in February, 2018 including all previously published papers and was analyzed using a random effects model.Results: There were no differences (p = 0.88) when comparing hypertrophy at the whole muscle (4.6%) and individual fiber level (7.0%), but significantly larger (p < 0.001) strength gains were observed at the whole muscle level (43.3%) relative to the individual fiber (19.5%). Additionally, there was an increase in the specific tension of type 1 muscle fibers (p = 0.013), but not type 2 muscle fibers (p = 0.23) which was driven by similar increases in strength (type 1: 17.5%, type 2A: 17.7%), despite differences in muscle size (type 1: 6.7%, type 2A: 12.1%).Conclusion: These results support the hypothesis that the neural adaptations play a large role in increasing isotonic whole muscle strength, but also demonstrate that an improvement in specific tension of type 1 muscle fibers is present. These results would suggest that some mechanism intrinsic to the muscle fiber, and independent of muscle growth, may also be contributing to strength increases in response to resistance exercise providing an avenue for future research. [ABSTRACT FROM AUTHOR]

Copyright of Baghdad Science Journal is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Males typically outperform females in Olympic-style weightlifting, as judged by total weight lifted, and similarly heavier athletes outperform lighter athletes. Current methods can standardise weightlifting performances across body mass to compare different body mass classes, but they do not address the sex gap. This study introduces a novel approach that puts male and female performances on a single unified scale, across the range of body mass, allowing mixed sex teams to be compared. The method uses standardised residuals or "z-scores" derived from models of performance regressed on sex and body mass fitted by GAMLSS (generalised additive models for location, scale and shape). Reference data come from the International Weightlifting Federation (IWF) world championships and Olympics 2017–2023. To ensure the validity of the model for ranking team performances in the future, results from 2000 to 2023 were compared and shown to be stable over time. A web application is available to aid athletes, coaches and health professionals to compare performances and monitor progress over time. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Applied Sports Sciences - Arabic is the property of Alexandria University, Faculty of Physical Education, Abu Qir and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background/objectives: Considering the diverse symptomatology of COVID-19—ranging from mild to severe cases—multi-professional interventions are crucial for enhancing physical recovery, nutritional status, and mental health outcomes in affected patients. Thus, this study aimed to investigate the effects of such an intervention on health-related physical fitness and biomarkers in overweight COVID-19 survivors with varying degrees of symptom severity after 8 weeks and 16 weeks. Methods: This non-randomized clinical trial included 59 overweight COVID-19 survivors (32 males and 27 females) divided into three groups: mild (n = 31), moderate (n = 13), and severe/critical (n = 15). The participants underwent a multi-professional program and were assessed for anthropometric and body composition (primary outcome), as well as physical fitness and biochemical markers (secondary outcome) 8 and 16 weeks before the intervention. Results: After 8 weeks, time effects were observed for the maximum isometric handgrip strength (p < 0.001), maximum isometric lumbar-traction strength (p = 0.01), flexibility (p < 0.001), abdominal strength–endurance (p < 0.001), the sit-and-stand test (p < 0.001), maximum oxygen consumption (p < 0.001), and distance covered in the 6 min walk test (p < 0.001). Additionally, time effects were also observed for fat mass (p = 0.03), body fat percentage (p = 0.02), abdominal circumference (p = 0.01), total cholesterol (p < 0.001), low-density lipoproteins (p < 0.001), and glycated hemoglobin (p < 0.001), with lower values after multi-professional interventions. After 16 weeks, the systolic and diastolic blood pressure showed significant reductions independently of the intervention group (p < 0.001). Conclusion: These findings suggest that multi-professional interventions can provide substantial benefits for post-COVID-19 patients, regardless of the severity of their initial symptoms. [ABSTRACT FROM AUTHOR]

The prediction of one-repetition maximum (1RM) using the submaximal load–velocity relationship (LVR) is highly relevant for the field of strength and conditioning. The optimal minimum velocity threshold (MVT) was recently proposed to increase the accuracy of 1RM predictions. However, using the average optimal MVT would allow for more practical estimations. LVRs of the free-weight back squat were obtained in 53 participants, throughout 2 sessions. LVRs were obtained using the multi- and two-point methods. Estimations of 1RM were made based on the average actual MVT (1RM velocity) and the average optimal MVT. The accuracy of 1RM predictions was examined using absolute-percent error and Bland-Altman plots. Cross-validation was performed using a leave-one-out approach. The number of selected loads did not affect the slope, y-intercept, optimal MVT or the accuracy of 1RM predictions. Predictions based on the average optimal MVT displayed greater accuracy than those obtained with the average actual MVT (~6% vs. ~8% absolute-percent error, respectively). However, wide 95% limits of agreement (LoA) were found between actual and estimated 1RM using both approaches (~13%1RM). The average optimal MVT offers more accurate 1RM estimations than the average actual MVT. However, errors prove substantial, making it challenging to precisely track minor changes in 1RM. [ABSTRACT FROM AUTHOR]

Background: Our systematic review aimed to critically evaluate empirical literature describing the association of muscle-strengthening exercise (MSE) with recurrence and/or mortality among breast cancer survivors. Methods: We included English-language empirical research studies examining the association between MSE and recurrence and/or mortality among females diagnosed with breast cancer. Seven databases (MEDLINE, PsycINFO, Embase, Scopus, Web of Science, Cochrane CENTRAL, and CINAHL) were searched in September 2023. Quality was appraised using the Mixed Methods Appraisal Tool. Results are summarized descriptively. Results: Five sources were identified. MSE measurement differed in relation to the description of the MSE (i.e., muscle-strengthening vs. strength training), examples of activities (e.g., sit-ups or push-ups vs. calisthenics vs. circuit training), and exercise frequency (i.e., days vs. times/week). Findings offer provisional evidence that some MSE may lower the hazards of recurrence and mortality. This association may vary by race, weight status, and menopausal status. Conclusions: In summary, limited available evidence suggests that MSE may lower the hazards of recurrence and mortality. More consistent measurement and analyses would help generate findings that are more readily comparable and applicable to inform clinical practice. Further research is needed to improve understanding of the strength and differences of these associations among underserved and underrepresented women. [ABSTRACT FROM AUTHOR]

A large corpus of data obtained by means of empirical study of neuromuscular adaptation is currently of limited use to athletes and their coaches. One of the reasons lies in the unclear direct practical utility of many individual trials. This paper introduces a mathematical model of adaptation to resistance training, which derives its elements from physiological fundamentals on the one side, and empirical findings on the other. The key element of the proposed model is what is here termed the athlete's capability profile. This is a generalization of length and velocity dependent force production characteristics of individual muscles, to an exercise with arbitrary biomechanics. The capability profile, a two-dimensional function over the capability plane, plays the central role in the proposed model of the training-adaptation feedback loop. Together with a dynamic model of resistance the capability profile is used in the model's predictive stage when exercise performance is simulated using a numerical approximation of differential equations of motion. Simulation results are used to infer the adaptational stimulus, which manifests itself through a fed back modification of the capability profile. It is shown how empirical evidence of exercise specificity can be formulated mathematically and integrated in this framework. A detailed description of the proposed model is followed by examples of its application-new insights into the effects of accommodating loading for powerlifting are demonstrated. This is followed by a discussion of the limitations of the proposed model and an overview of avenues for future work. [ABSTRACT FROM AUTHOR]

Copyright of Studia Universitatis Babes-Bolyai, Educatio Artis Gymnasticae is the property of Babes-Bolyai University, Cluj-Napoca, Romania and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Education Policy Analysis Archives / Archivos Analíticos de Políticas Educativas / Arquivos Analíticos de Políticas Educativas is the property of Educational Policy Analysis Archives & Education Review and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Addresses the deficit in data regarding the efficacy of training children for weightlifting. Controversy surrounding strength training and weightlifting for children; Discussion on the issue of safety of children in competitive weightlifting; Sex difference in degree of improvement in lift total.