Effects of nordic walking training on gait and exercise tolerance in male ischemic heart disease patients.

This technique-focused observational study explores the impact of a 6-week Nordic Walking (NW) program on physiological and biomechanical aspects in ischemic heart disease (IHD) patients. Twelve male IHD patients (66.2 ± 5.2 years, 12.2 ± 7.5 years of disease duration) were evaluated pre- and post-training for (i) gait parameters, (ii) exercise tolerance using electrocardiographic (ECG) stress test, (iii) a 6-min walk test (6MWT). The NW training, adhering to IHD patient guidelines, involved a 100-m walk at a self-selected, preferred speed without sticks, with classic NW sticks and mechatronic sticks. A mechatronic measuring system, specifically engineered for measuring, diagnosing and monitoring the patient's gait, was integrated into mechatronic sticks. Post-training, significant enhancements were observed in ECG stress test duration, metabolic equivalency, and 6MWT distance, irrespective of the stick type. However, no significant changes were noted in spatiotemporal parameters concerning the measured side, stick utilisation, or type. The results suggest that NW training boosts exercise capacity and refines gait mechanics in male IHD patients. However, the improvement in exercise capacity was not linked to changes in gait mechanics from NW training but rather to the movement during NW gait. Hence, the key to enhancing exercise capacity in IHD patients is the movement during NW gait, not the quality of gait mechanics.

Mechatronic Pole System for Monitoring the Correctness of Nordic Walking.

Marching with Nordic walking (NW) poles is a common form of physical activity. It is recommended in the treatment and rehabilitation of many diseases. NW's wide range of applications in rehabilitation and its effectiveness are limited by the need for experienced physiotherapists to supervise patients during the training. A prerequisite for good rehabilitation results is correctly using the poles during walking. Essential parameters of NW include the angle of inclination of the pole, the force of the pole on the ground, and proper coordination of performed movements. The purpose of this paper is to present the design and operating principle of a mechatronic NW pole system for measuring and recording the gait parameters. The subject of the work was the assessment of the usefulness of the mechatronic NW pole system for phases identified during marching. The study was conducted in field conditions. The study's main objective was to compare the obtained results from the developed system with those of a commercial system for measuring foot pressure distributions on the ground. The paper also presents sample results measuring walkers' gait with NW poles in the field and the resulting gait phase analysis.

Application of numerical simulation studies to determine dynamic loads acting on the human masticatory system during unilateral chewing of selected foods.

Introduction: This paper presents its kinematic-dynamic computational model (3D) used for numerical simulations of the unilateral chewing of selected foods. The model consists of two temporomandibular joints, a mandible, and mandibular elevator muscles (the masseter, medial pterygoid, and temporalis muscles). The model load is the food characteristic (i), in the form of the function Fi = f(Δhi)-force (Fi) vs change in specimen height (Δhi). Functions were developed based on experimental tests in which five food products were tested (60 specimens per product). Methods: The numerical calculations aimed to determine: dynamic muscle patterns, maximum muscle force, total muscle contraction, muscle contraction corresponding to maximum force, muscle stiffness and intrinsic strength. The values of the parameters above were determined according to the mechanical properties of the food and according to the working and non-working sides. Results and Discussion: Based on the numerical simulations carried out, it can be concluded that: (1) muscle force patterns and maximum muscle forces depend on the food and, in addition, the values of maximum muscle forces on the non-working side are 14% lower than on the working side, irrespective of the muscle and the food; (2) the value of total muscle contraction on the working side is 17% lower than on the non-working side; (3) total muscle contraction depends on the initial height of the food; (4) muscle stiffness and intrinsic strength depend on the texture of the food, the muscle and the side analysed, i.e., the working and non-working sides.

No Influence of Mechatronic Poles on the Movement Pattern of Professional Nordic Walkers.

This study compared selected temporal and kinematic parameters of normal gait and Nordic Walking (NW) performed with classic and mechatronic poles (classic poles equipped with sensors). It was assumed that equipping NW poles with sensors for biomechanical gait analysis would not impair the NW walking technique. Six professional NW instructors and athletes, including three women, participated in the study. The MyoMotion MR3 motion analysis system was used to collect gait kinematic variables. The subject's task was to cover a 100-m distance with three types of gait: a gait without poles, a gait with classic NW poles, and a gait with mechatronic poles at the preferred speed. Parameters were measured both on the right and left sides of the body. No significant differences were found between gait types for three temporal parameters: step cadence, step, and stride time. For the other variables, all the differences identified were between free-walking and walking with poles, with no differences between standard and mechatronic poles. For nine kinematic parameters, differences between free-walking and walking with poles for both the left and right sides were found, while no differences were due to the pole type. All temporal parameters were characterized by symmetry, while among kinematic parameters, only two were asymmetrical (shoulder abduction-adduction in walking with regular poles and elbow flexion-extension in walking without poles). Equipping classic NW poles with additional signaling and measuring devices (mechatronic poles) does not impair the NW technique, making it possible to use them in further studies of gait biomechanics.

Prediction of Motion Intentions as a Novel Method of Upper Limb Rehabilitation Support.

This article is devoted to the novel method of upper limb rehabilitation support using a dedicated mechatronic system. The mechatronic rehabilitation system's main advantages are the repeatability of the process and the ability to measure key features and the progress of the therapy. In addition, the assisted therapy standard is the same for each patient. The new method proposed in this article is based on the prediction of the patient's intentions, understood as the intentions to perform a movement that would be not normally possible due to the patient's limited motor functions. Determining those intentions is realized based on a comparative analysis of measured kinematic (range of motion, angular velocities, and accelerations) and dynamic parameter values, as well as external loads resulting from the interaction of patients. Appropriate procedures were implemented in the control system, for which verification was conducted via experiments. The aim of the research in the article was to examine whether it is possible to sense the movement intentions of a patient during exercises, using only measured load parameters and kinematic parameters of the movement. In this study, the construction of a mechatronic system prototype equipped with sensory grip to measure the external loads, control algorithms, and the description of experimental studies were presented. The experimental studies of the mechanism were aimed at the verification of the proper operation of the system and were not a clinical trial.

Modelling of the forces acting on the human stomatognathic system during dynamic symmetric incisal biting of foodstuffs.

A major stage in the preparation of a computational model of the human stomatognathic system is the determination of the values of the forces for the adopted loading configuration. In physiological conditions, food is a factor having a significant effect on the values of the loads acting on the stomatognathic system. Considering that the act of mastication is a complex process, this research undertook to determine the forces (bite forces, muscular forces and temporomandibular joint reaction forces) acting on the stomatognathic system during the dynamic symmetric incisal biting of selected foodstuffs. The investigations were divided into two stages: (1) experimental tests and (2) numerical simulations. In the first stage, classic force-displacement characteristic curves (Fi-Δh) were determined for the food while in the second stage, the curves were used as a dynamic stomatognathic system model load function. One of the most important results of this research is that the food characteristic in the form of a force-displacement function has been shown to have a significant effect not only on the values of the muscular forces and the temporomandibular joint reaction forces, but also on their curves during the dynamic loading of the stomatognathic system. The analysis of the results indicates that Fi-Δh has an effect on not only the (active and passive) forces, but also on other parameters, such as stress, deformation, displacement, and probably the rigidity of the muscles.

Effect of foodstuff on muscle forces during biting off.

PURPOSE: The subject of this research is the human stomatognathic system and the process of biting off various foodstuffs. METHODS: The research was divided into two stages - an experimental stage and a computational stage. In the first stage, tests were carried out to determine the force-displacement characteristics for the biting off food. For this purpose five different foodstuffs were tested in a testing machine and their strength characteristics were determined. The aim of the second stage was to build a computational model of the human cranium-mandible system and to run simulations of the process of biting off food in order to determine the muscular forces as a function of the food. A kinematic scheme was developed on the basis of a survey of the literature on the subject and used to create a computational model of the human stomatognathic system by means of dynamic analysis software (LMS DADS). Only the masseter muscle, the temporal muscle and the medial pterygoid muscle were taken into account - the lateral pterygoid muscle was left out. RESULTS: The simulations yielded the basic kinematic and dynamic parameters characterizing the muscles. CONCLUSIONS: Summing up, weaker occlusion forces are needed to bite off today's foodstuffs than the forces which the mastication muscles are capable of generating. Determined in the article the general equations will enable identification of the muscular forces acting on the mandible during biting off, performing basic strength calculations, and will also give an answer to which of the products the patient after a surgical procedure will be able to consume.