Adjusted Landing Technique Reduces the Load on the Achilles Tendon in Badminton Players.

Achilles tendon (AT) rupture is common among recreational male badminton players. We hypothesize that a landing technique following forehand jump strokes with the landing foot in a neutral position often performed by recreational players and occasionally by elite players may expose the AT to higher loads than a scissor kick jump (SKJ) technique with the leg/foot externally rotated. The study aimed to investigate if recreational players could reduce the load in the AT when adopting the SKJ technique compared to their habitual landing technique with the foot in a neutral position and secondarily to compare the AT force between recreational players and elite players.

External and internal loads during the competitive season in professional female soccer players according to their playing position: differences between training and competition.

The aim of this study was to compare external (EL) and internal loads (IL) during training sessions compared to official matches between elite female soccer players according to their playing position.Training and match data were obtained during the 2017/18 season from eighteen players (age: 26.5±5.

Biomechanical and neuromuscular comparison of single- and multi-planar jump tests and a side-cutting maneuver: Implications for ACL injury risk assessment.

Background: Non-contact anterior cruciate ligament (ACL) injuries are a major problem among adolescent female soccer and handball players. Therefore, the aim of this study was to examine if known biomechanical and neuromuscular ACL injury risk factors obtained from single-planar jump-landings and multi-planar side-jumps can resemble the demands of side-cutting maneuvers, a known high-risk ACL injury movement for this population.

Methods: Twenty-four female soccer and handball players (mean ± SD: age: 17 ± 1 year; height: 172 ± 66 cm; mass: 67 ± 9 kg) performed a series of functional tasks including two single-planar jump-landings, two multi-planar side-jumps and a sports-specific side-cutting maneuver on their dominant leg.

Biomechanical loading during running: can a two mass-spring-damper model be used to evaluate ground reaction forces for high-intensity tasks?

Running impact forces expose the body to biomechanical loads leading to beneficial adaptations, but also risk of injury. High-intensity running tasks, especially, are deemed highly demanding for the musculoskeletal system, but loads experienced during these actions are not well understood. To eventually predict GRF and understand the biomechanical loads experienced during such activities in greater detail, this study aimed to (1) examine the feasibility of using a simple two mass-spring-damper model, based on eight model parameters, to reproduce ground reaction forces (GRFs) for high-intensity running tasks and (2) verify whether the required model parameters were physically meaningful.

The feasibility of predicting ground reaction forces during running from a trunk accelerometry driven mass-spring-damper model.

Background: Monitoring the external ground reaction forces (GRF) acting on the human body during running could help to understand how external loads influence tissue adaptation over time. Although mass-spring-damper (MSD) models have the potential to simulate the complex multi-segmental mechanics of the human body and predict GRF, these models currently require input from measured GRF limiting their application in field settings. Based on the hypothesis that the acceleration of the MSD-model's upper mass primarily represents the acceleration of the trunk segment, this paper explored the feasibility of using measured trunk accelerometry to estimate the MSD-model parameters required to predict resultant GRF during running.

The impact of start strategy on start performance in alpine skiing exists on flat, but not on steep inclines.

Here, we explored the relationship between incline and start strategy during alpine skiing. Eight FIS skiers performed starts on a flat (3°) and steep (21°) incline employing five different strategies. Their times, trajectories and velocities were monitored with a GNSS system and video.

Training Load Monitoring in Team Sports: A Novel Framework Separating Physiological and Biomechanical Load-Adaptation Pathways.

There have been considerable advances in monitoring training load in running-based team sports in recent years. Novel technologies nowadays offer ample opportunities to continuously monitor the activities of a player. These activities lead to internal biochemical stresses on the various physiological subsystems; however, they also cause internal mechanical stresses on the various musculoskeletal tissues.

Mechanical Player Load™ using trunk-mounted accelerometry in football: Is it a reliable, task- and player-specific observation?

The aim of the present study was to examine reliability and construct convergent validity of Player Load™ (PL) from trunk-mounted accelerometry, expressed as a cumulative measure and an intensity measure (PL · min). Fifteen male participants twice performed an overground football match simulation that included four different multidirectional football actions (jog, side cut, stride and sprint) whilst wearing a trunk-mounted accelerometer inbuilt in a global positioning system unit. Results showed a moderate-to-high reliability as indicated by the intra-class correlation coefficient (0.

The Relationship Between Whole-Body External Loading and Body-Worn Accelerometry During Team-Sport Movements.

Purpose: To investigate the relationship between whole-body accelerations and body-worn accelerometry during team-sport movements.

Methods: Twenty male team-sport players performed forward running and anticipated 45° and 90° side-cuts at approach speeds of 2, 3, 4, and 5 m/s. Whole-body center-of-mass (CoM) accelerations were determined from ground-reaction forces collected from 1 foot-ground contact, and segmental accelerations were measured from a commercial GPS accelerometer unit on the upper trunk.

Biomechanics of the ski cross start indoors on a customised training ramp and outdoors on snow.

An effective start enhances an athlete's chances of success in ski cross competitions. Accordingly, this study was designed to investigate the biomechanics of start techniques used by elite athletes and assess the influence of different start environments. Seven elite ski cross athletes performed starts indoors on a custom-built ramp; six of these also performed starts on an outdoor slope.

Using accelerometry to quantify deceleration during a high-intensity soccer turning manoeuvre.

Abstract The mechanics of cutting movements have been investigated extensively, but few studies have considered the rapid deceleration phase prior to turning which has been linked to muscle damage. This study used accelerometry to examine the influence of turning intensity on the last three steps of a severe turn. Ten soccer players performed 135° "V" cuts at five different intensities.

Psychiatric disorders in individuals diagnosed with infantile autism as children: a case control study.

The objective of this study was to compare the prevalence and types of psychiatric disorders in a clinical sample of 118 individuals diagnosed as children with infantile autism (IA) with psychiatric disorders in 336 matched controls from the general population using data from the nationwide Danish Psychiatric Central Register. The average observation time was 32.5 years, and mean age at follow-up was 40.

Pervasive developmental disorders and criminal behaviour: a case control study.

The prevalence and pattern of criminal behaviour in a population of 313 former child psychiatric in-patients with pervasive developmental disorders were studied. The patients were divided into three subgroups and compared with 933 matched controls from the general population. Age at follow-up was between 25 years and 59 years.

Autoimmune diseases in parents of children with infantile autism: a case-control study.

This register study compared the rates and types of autoimmune disease in the parents of 111 patients (82 males, 29 females; mean age at diagnosis 5y 5mo [SD 2y 6mo]) with infantile autism (IA) with a matched control group of parents of 330 children from the general population. All parents were screened through the nationwide Danish National Hospital Register. We inquired about 35 autoimmune diseases during an observation period of 27 years.

Psychiatric disorders in the parents of individuals with infantile autism: a case-control study.

Background: The rates and types of psychiatric disorders were studied in the parents of individuals with infantile autism (IA).

Sampling And Methods: To estimate the prevalence and types of psychiatric disorders, the parents of 115 individuals with IA and the parents of 330 controls from the general population were screened through the nationwide Danish Psychiatric Central Register covering a period of 33 years. The IA individuals had been seen as in-patients at two university clinics of child psychiatry during a 25-year period and had been referred from the entire country of Denmark.