Search results for "liikeoppi"

A hierarchical cluster analysis to determine whether injured runners exhibit similar kinematic gait patterns

2020

Previous studies have suggested that runners can be subgrouped based on homogeneous gait patterns, however, no previous study has assessed the presence of such subgroups in a population of individuals across a wide variety of injuries. Therefore, the purpose of this study was to assess whether distinct subgroups with homogeneous running patterns can be identified among a large group of injured and healthy runners and whether identified subgroups are associated with specific injury location. Three‐dimensional kinematic data from 291 injured and healthy runners, representing both sexes and a wide range of ages (10‐66 years) was clustered using hierarchical cluster analysis. Cluster analysis r…

Effects of barbell back squat stance width on sagittal and frontal hip and knee kinetics

2018

Different stance widths are commonly utilized when completing the barbell back squat during athletic general preparedness training. Width manipulation is thought to influence sagittal plane stimuli to the hip and knee extensors, the primary extensor musculature in the squat. However, how width manipulation affects frontal plane stimuli is less understood. Knowledge of hip and knee net joint moments (NJM) could improve exercise selection when aiming to improve sport-specific performance and prevent injuries. Fourteen adult amateur rugby athletes were recruited for this study. After a familiarization period, participants performed wide- (WIDE, 1.5× greater trochanter width) and narrow-stance …

The gait is less stable in children with cerebral palsy in normal and dual-task gait compared to typically developed peers

2021

There is limited evidence about gait stability and its alteration by concurrent motor and cognitive tasks in children with cerebral palsy (CP). We examined gait stability and how it is altered by constrained cognitive or motor task in CP and their typically developed (TD) controls. Gait kinematics were recorded using inertial-measurement units (IMU) from 18 patients with hemiplegia (13.5 +/- 2.4 years), 12 with diplegia (13.0 +/- 2.1 years), and 31 TD controls (13.5 +/- 2.2 years) during unconstrained gait, and motor (carrying a tray) and cognitive (word naming) task constrained gait at preferred speed (similar to 400 steps/task). Step duration, its standard deviation and refined-compound-m…

The more you move, the more action you construct : a motion capture study on head and upper-torso movements in constructed action in Finnish Sign Lan…

2020

Abstract This paper investigates, with the help of motion capture data processed on corpus principles, the characteristics of head and upper-torso movements in constructed action and regular narration (i.e., signing without constructed action) in FinSL. Specifically, the paper evaluates the validity of two arguments concerning constructed action: that constructed action forms a continuum with regular narration, and that constructed action divides into three subtypes (i.e., overt, reduced, and subtle). The results presented in the paper support the first argument but not directly the second one. Because of the ambiguous position of reduced constructed action in between subtle and overt const…

The standing knee lift test is not a useful screening tool for time loss from low back pain in youth basketball and floorball players

2021

Abstract Objectives The aim of this study was to investigate the association between pelvic kinematics during the standing knee lift (SKL) test and low back pain (LBP) in youth floorball and basketball players. Design A prospective cohort study. Setting Finnish elite youth floorball and basketball players. Participants Finnish elite youth female and male floorball and basketball players (n = 258, mean age 15.7 ± 1.8). Main outcome measures LBP resulting in time loss from practice and games was recorded over a 12-month period and verified by a study physician. Associations between LBP and sagittal plane pelvic tilt and frontal plane pelvic obliquity during the SKL test as measured at baselin…

Effects of Aerodynamic Drag and Drafting on Propulsive Force and Oxygen Consumption in Double Poling Cross-country Skiing

2022

Purpose To investigate the effects of aerodynamic drag and drafting on propulsive force (FPROP), drag area (CDA), oxygen cost (V˙O2), metabolic rate (E˙) and heart rate (HR) during roller skiing on a treadmill in a wind tunnel using the double poling technique. A secondary aim was to investigate the effects of wind versus no-wind test conditions on the same physiological parameters. Methods 10 subjects of each gender participated in the experiments. One pair of skiers of the same gender roller skied simultaneously in line with the air flow; the distance between the skiers was ~2.05 m. Each pair was tested as follows: I) with wind, leading; II) with wind, drafting; III) without wind. The tre…

Kävelyn biomekaniikka MBT-kengällä, tavallisella kengällä ja paljain jaloin hiekalla

2008

Using deep neural networks for kinematic analysis: Challenges and opportunities

2020

Kinematic analysis is often performed in a lab using optical cameras combined with reflective markers.\ud With the advent of artificial intelligence techniques such as deep neural networks, it is now possible\ud to perform such analyses without markers, making outdoor applications feasible. In this paper I summarise\ud 2D markerless approaches for estimating joint angles, highlighting their strengths and limitations.\ud In computer science, so-called ‘‘pose estimation” algorithms have existed for many years. These methods\ud involve training a neural network to detect features (e.g. anatomical landmarks) using a process called\ud supervised learning, which requires ‘‘training” images to be …

Markerless 2D kinematic analysis of underwater running : A deep learning approach

2018

Kinematic analysis is often performed with a camera system combined with reflective markers placed over bony landmarks. This method is restrictive (and often expensive), and limits the ability to perform analyses outside of the lab. In the present study, we used a markerless deep learning-based method to perform 2D kinematic analysis of deep water running, a task that poses several challenges to image processing methods. A single GoPro camera recorded sagittal plane lower limb motion. A deep neural network was trained using data from 17 individuals, and then used to predict the locations of markers that approximated joint centres. We found that 300–400 labelled images were sufficient to tra…

Rifle and aiming point accelerations do not differ between the most and least accurate shots in biathlon shooting within an athlete

2023

Abstract Study aim: As studies from shooting disciplines other than biathlon have observed associations between weapon accelerations and shooting performance, this study investigated whether accelerations of the rifle stock and aiming point (the point on the target where the rifle is aimed at) are associated with shooting performance, and differences in rifle and aiming point accelerations between the most and least accurate shots. Further, associations between rifle and aiming point accelerations were studied. Materials and methods: Shooting performance (HitDist, hit point distance from the center of the target) along with rifle and aiming point accelerations were measured from nine biathl…