PROGRAMMED STRENGTH TRAINING USING A COMPUTERIZED ISOTONIC STAND

One of the very important tasks of the theory and practice of modern training is searching for new methods, in order to improve the efficiency of the training process. Nowadays muscle strength seems to be the most significant factor which influences performance in different kinds of sport. On the other hand development of the strength level is particularly difficult among highperformance athletes. The aim of this paper is to present computer-controlled strength training using a special stand for museie strength training and diagnostics. The stand consists of three main sub-assembles: -mechanical part (steel bedplate, bar with replaceable holders, bench for exercises). -hydraulic resistance module, -efectronic part (valve controller, AlC converter, PC 486/100). A special computer program allows force stabilization in the full range of motion (isotonic resistance) and registration of the basic parameters of movement. The computer-controlled training program includes three basic strength training methods: -repetition (50-80% RM, 4-8 series, 1020 reps); -maximal efforts (90-100% RM, 1-5 series, 1-3 reps); -speed-strength (40-45% RM, 4-8 series, 8-12 reps). Besides these methods the user could exercise according to his (or her) individual program. There are four main indices describing training loads, which can be controlled: resistance, number of series, number of reps and rest periods. Various popular exercises as: bench press, seated press, squats, both-or one-hand pulls, biceps curl. bent over row, etc. can be performed on the stand. The computer program enables registration of the force and displacement of the bar and on this base calculation maximal and mean values of several important parameters of the workout: mechanical power, velocity of the bar, work per rep(s). set(s) and unit(s). The initial resistance is established during the special trials, assessing the speedstrength abilities of the user, and changes of training loads are accomplished automatically, according to achieved results in these trials. The computer-controlled strength training performed on the isotonic stand is designed for both, beginners and highperformance athletes. The equipment can be used under field or laboratory conditions, because it is very safe, not noisy and not too large. REFERENCES Ariel G., Penny M., Saar D.. Selinger A. (1990): Computer-controlled strength training program for the U.S. National Women's Volleyball Team. COTO Research Center. Abstract form. Eliasz J. (1993): Trening sity mi~sniowej w pilee r~cznej (Strength training in handball) Sport Wyczynowy 9/10:21-28. Kannus P. (1994): Isokinetic evaluation of muscular performance: Implications for museie testing and rehabilitation. Int. Journal of Sports Medicine 15. Suppt. 1:S11-18. Kemp M. (1989): Strength training principles. Modem Athlete and Coach 27:11-12. Pauletto B. (1991): Strength training for coaches. Human Kinetics. Champaign IL. Zatsiorsky V.M. (1995): Science and Practice of Strength Training. Human Kinetics. Champaign IL

AN ASSESSMENT OF SPEED-STRENGTH ABILITIES IN YOUNG MEN

INTRODUCTION Muscle strength is one of the most important factors in sport performance and other human activities -in this case it concerns the physical preparation of military pilots, particularly in order to develop the +Gz toleration. The study was designed to establish the parameters of speed-strength abilities of upper and lower extremities in young men. It allows us to find out the relationships between age, body mass, speed and muscle strength in order to improve the efficiency of weight training. METHODS One hundred young men (cadet-pilots) participated in the study. They were divided into two main groups: middle aviation school students (n=21; 16.0±1.1 years of age, 173.4±5.3 cm body height, 63.8±10.2 kg body weight) and the Polish Air-Force Academy students (n=79; 20.9±1.4 years of age, 178.0±5.7 cm b.h., 73.3±7.3 kg b.m.). In order to estimate the basic speed-strength parameters of upper and lower extremities both groups performed bench press and squats. Exercises were provided on a computerized stand (locally made) under isokinetic (co = 0.2 radIs) and isotonic (M = 20 Nxm) conditions. The subjects performed three trials with maximal effort to estimate the maximal speed (MS) and the maximal torque (MT) developed in the exercise. Descriptive statistics for each parameter as well as the t-test and Pearson's correlation matrix were used (

Investigation of cooling properties of the gaseous medium of a space station

An investigation of cooling properties of the gaseous medium was performed in the biosatellite Kosmos-936 as well as in the orbital complexes Soyuz-28/Salyut-6 and Soyuz-30/Salyut-6 with the aid of an especially constructed electric dynamic catathermometer. In this instrument current was measured which was necessary to keep a steady settled temperature of the sensing device. The investigation was performed because of the disturbed heat exhange of the human body caused by lack of natural convection in weightlessness. The instrument also enabled objective estimation of the temperature of the cosmonaut's ody in six optionally selected regions. The results obtained by means of the catathermometer will also enable defining the appropriate hygienic conditions of the gaseous medium of space stations

Pets as Sentinels of Human Exposure to Neurotoxic Metals

The idea that animals may be used as sentinels of environmental hazards pending over humans and the associated public health implications is not a new one. Nowadays pets are being used as bioindicators for the effects of environmental contaminants in human populations. This is of paramount importance due to the large increase in the worldwide distribution of synthetic chemicals, particularly in the built environment. Companion animals share the habitat with humans being simultaneously exposed to and suffering the same disease spectrum as their masters. Moreover, their shorter latency periods (due to briefer lifespans) enable them to act as early warning systems, allowing timely public health interventions. The rise on ethical constraints on the use of animals and, consequently, on the sampling they can be subjected to has led to the preferential use of noninvasive matrices, and in this case we are looking into hair. This chapter focuses in three non-essential metals: mercury, lead, and cadmium, due to their ubiquitous presence in the built environment and their ability of affecting the mammal nervous system. There is a fairly short amount of studies reporting the concentrations of these metals in pets’ hair, particularly for cats. These studies are characterized, and the metal concentrations corresponding to different parameters (e.g., age, sex, diet, rearing) are described in order to provide the reader with a general vision on the use of this noninvasive matrix on the studies conducted since the last two decades of the twentieth century.publishe

How Many Types of Critical Activities Exist? – A Conjecture That Needs a Proof

The Precedence Diagramming Method (PDM) is the prevalent scheduling technique used for temporal planning of projects. Critical paths require special attention during the course of planning as their lengths define the project duration. However, increasing/decreasing the duration of an activity on the critical path does not necessarily results in a longer/shorter project duration. Responses of the critical path in a PDM network for small changes of the duration of a critical activity can be classified into six categories, while nine different possible categories exist in theory. The modeling capabilities of PDM recently have been extended by the introduction of a) point-to-point relations, b) continuous relations, and c) non-linear activity (production-time) functions. The paper presents the following conjecture that needs a proof: The number of existing types of critical activities remains six when using the recently developed precedence relations and non-linear production-time functions for activities. The theory of the different types of critical activities is briefly discussed and the mathematical model of the generalized PDM technique is presented. An additional feature presented in the paper beyond defining the conjecture is the introduction of influence lines for project duration that have never been used in project management before. Influence lines can be of great help in understanding the nature of critical activities. Papers providing solutions or confuting this conjecture will be honored with the CCC 2017 award

Public-private partnership for earthquake mitigation involving retrofit and insurance

Public-Private Partnerships involving governments and insurers have been used worldwide for mitigation of natural-hazards. However, the implementation of such systems in developing countries presents problems for their key stakeholders. On the one hand, property owners are hesitant to purchase insurance or invest in retrofit projects due to cost considerations. On the other hand, insurers are reluctant to cover potential seismic losses, because of uncertainties about the risk. This study introduces an innovative Public-Private Partnership framework for property owners, insurers and governments to facilitate decisions related to hazard insurance and structural retrofit of vulnerable buildings. This framework can also help insurance firms reduce the level of corporate financial assets available for payment of compensation to their clients, as required by regulations aimed at reducing the risk of insurer insolvencies. Property owners are motivated to participate in the framework by extra mitigation subsidies from the government. While the government will be reimbursed for part of the cost of these retrofit projects by insurance firms, whose own savings will be achieved through reductions to legally mandated corporate capital. A case study is presented to demonstrate the feasibility of this approach for mitigating seismic risk to residential buildings in a rural area