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Urban ecology sees today the city nature as a green infrastructure providing ecosystem services to the urban dwellers, contributing to their welfare and a sustainable urban development. However, the concepts included in this view are not as new as it seems. Ecosystem services are just a reiteration of the ecological economy view of nature as a natural capital providing goods and services to the human society. Similarly, although increasing attention has been paid lately to the green infrastructure and its role in addressing challenges faced by the modern society, including the mitigation of climate change effects, it is less known that the concept, that started being used relatively recently, in the '90s, has emerged at the end of the 21st century in the works of the prominent landscape architects and urban planners Frederick Law Olmsted and Ebenezer Howard. They argued in their projects, revolutionary for that time, for the need to combat urban sprawl through a strategic planning of vegetated systems and corridors, known today as "green infrastructure". The designed components of the systems of urban parks and green spaces are similar to those of the "green infrastructure", consisting of nodes (core areas/hubs) and connections. The relationship between nature and human well-being (known today as "ecosystem services") and sustainability was also anticipated by their woks. Most importantly, these early researches demonstrated that the green infrastructure is not optional, but must be strategically devised, holistically planned, and properly managed. This work aims to revisit the old works from a modern perspective.

Introduction.* W. Mtiller-Limmroth (Munich) No mention is made of the relationships between physical movement and the central nervous system in the book "The ScientificView of Sport-Perspectives, Aspects, Issues". It is nevertheless a fact that, if a movement is to proceed as desired, it is the nervous system which must ensure that no disturbing environmental forces modify the desired movement in a sense contrary to the will of its executant. In every movement, therefore, the plan and intention of the movement must coincide with its realisation. The muscles concerned must be co-ordinated to this end, agonists and antagonists must harmonise in effecting a useful and purposeful movement. This harmony is the essential factor of the co-ordination of movement. It involves the co-ordination of all processes that are released in the organism for the execution of a certain movement in its correct sequence. Exercise and training are the methods for developing the co-ordination of movement, in which stimulating and inhibiting processes play the principal part. The result of such training is skill, i. e. good co-ordination of the fine motor movements of parts of the motor system, and dexterity, i. e. the well balanced co-ordination of the whole motor system of an organism.The physiological and regulatory processes which assure this co-ordination of movement are the changes in tension and length of the skeletal muscles. In these processes, the pulses from the peripheral and central nervous system which initiate such activities are all conducted to the motoneurons in the spinal cord and thus to a common final path. The most important problem in the regulation of posture and movement, therefore, is the way in which a co-ordination of stimulation is accomplished in the anterior horn cells of the spinal cord. It must be ensured that muscle activity is harmonised without the necessity of conscious corrections with the environmental influences which impinge upon a person through his senses; at the same time, this activity must also be subject to arbitrary control. In addition, it is important how the motor system of the body is correlated with other somatic and autonomic functions of the central nervous system.The active body in the motor system is the motor unit which is made up of the alpha-motoneuron, its neurites and the muscle fibres which it reaches by way of the motor end-plates. The modulation of arbitrary activity is effected through a spatial summation, i.e. through the number of motor units which come into action, and through a time summation, i. e. the number of pulses coming from the alpha-motoneuron and resulting in a tetaniformic action.Here a part is played by a peripheral regulation system, the proprioceptive reflex whose reflex arc begins with the extensible muscle spindles. Pulses from the centre * Translated from German. 19 Olympia Congress Report 289 Motor Learning and Training in Sport part of the spindle are led by afferent fibres to the spinal ganglion, which makes synaptic contact with the alpha-motone...