The aim of this review is to describe the effects induced by local temperature changes on human skeletal muscle metabolism. More specifically, we will consider the influence of temperature on the mechanical properties of muscle contraction, on aerobic metabolism, anaerobic metabolism and on the Lohmann reaction. The text has been voluntarily organized on the basis of a simple bioenergetic model describing the different energy fluxes appearing in the muscle system. This approach should better highlight some of the points that still need to be investigated. Although it was not always possible to restrict the discussion to human muscle, the references report mainly data obtained directly on humans or on isolated human fibres. A short comment on skeletal muscle temperature measurement techniques, on humans, is also included.
A safe, convenient, sound and healthy living environment is the prerequisite for a good house for the people with special needs. The intention of making a house in such a way that it solves basic problems of fixture and fittings. However the construction phase of a good house is a critical to design inside and outside structures. Often the builders do not know all the factors to be considered that can maintain a safe, hygienic and healthy environment. It is believed that when housing is ergonomically furnished, then a maximum benefit will be achieved. To meet with an individual's specific needs, an analysis of user's requirement is the most important factors to be considered in the design of special houses. Users' data such as anthropometric dimension, users' choices and preferences are also necessary to design a suitable living environment. In this regard, this paper illustrates some ergonomic features to design and develop good houses in terms of how people with restricted mobility and communication can truly be helped residing in their homes and performing their daily living activities. Users' social, medical and engineering needs are highlighted following the process of disability, ageing, or impairments to achieve the maximum level of benefits, and ensuring safe and sound living.
An assistive device is designed to accommodate the special needs of disability that can help people with physical, mental or cognitive challenges go through their day-to-day activities with less difficulty. An assistive device usually provide alternatives to functional limitations imposed by the client's disorder, and thereby minimising rehabilitation costs. It is therefore important to know about how assistive technology will function in all the possible aspects of such disabilities and impairements. When designing a technical device, particularly in conjunction with the target user group, ergonomic issues are therefore important to find out the extent to which an assistive device is convenient or not, and to check the quality performance of assistive technology. Since the question of the match or mismatch of an assistive device and a disabled person requires much attention, it is therefore suggested that paying attention on how an assistive device be ergonomically designed and developed is important. Ergonomic applications are to be applied for increasing motivation of prospective customers through innovative performance of AT. The authors believe that there are opportunities in ergonomic applications to manufacture an assistive device as unique, cost saving, and allows less exertation and reduces energy consumption when it is used. Hence this paper highlights human factors and/or ergonomics consideration in the process of design and development of assistive devices synchronising with gerontechnological research and development aiming to emphasise user's requirement.
The purpose of the present study was to examine the effect of water temperature on the human body during low-intensity prolonged swimming. Six male college swimmers participated in this study. The experiments consisted of breast stroke swimming for 120 minutes in 23°C, 28°C and 33°C water at a constant speed of 0.4 m · sec-1 in a swimming flume. The same subjects walked on a treadmill at a rate of approximately 50% of maximal oxygen uptake (VO2max) at the same relative intensity as the three swimming trials. Rectal temperature (Tre) in 33°C water was unchanged during swimming for 120 minutes. Tre during treadmill walking increased significantly compared to the three different swimming trials. Tre, mean skin temperature (Tsk) and mean body temperature (Tb) in 23°C and 28°C water decreased significantly more than in both the 33°C water and walking on land. VO2 during swimming in 23°C water increased more than during swimming in the 28°C and 33°C trials; however, there were no significant differences in VO2 between the 23°C swimming trial and treadmill walking. Heart rate (HR) during treadmill walking on land increased significantly compared with HR during the three swimming trials. Plasma adrenaline concentration at the end of the treadmill walking was higher than that at the end of each of the three swimming trials. Noradrenaline concentrations at the end of swimming in the 23°C water and treadmill walking were higher than those during the other two swimming trials. Blood lactate concentration during swimming in 23°C water was higher than that during the other two swimming trials and walking on land. These results suggest that the balance of heat loss and heat production is maintained in the warm water temperature. Therefore, a relatively warm water temperature may be desirable when prolonged swimming or other water exercise is performed at low intensity.
The objective of the study was to compare blood pressure and endocrine responses in a cold pressure test in young healthy subjects who had shown increased blood pressure during an acutely increased sodium intake. Subjects (n=53) added 121 mmol sodium into their normal diet for one week. If the mean arterial pressure had increased by a minimum of 5 mmHg compared to the control measure, they were selected for the experiments. The selected subjects (n=8) were given 121 mmol supplemental sodium d-1 for 14 days after which they immersed the right hand into a cold (+10 °C) water bath for 5 min. The blood pressure increased (P<0.05) during the test and was independent of the sodium intake. The plasma noradrenaline increased from 2.41 ± 0.38 nmol l-1 to 2.82 ± 0.42 nmol l-1 (P<0.05) with normal diet and from 1.85 ± 0.29 nmol l-1 to 2.40 ± 0.37 nmol l-1 (P<0.05) with high sodium diet. The starting concentrations and the endpoint concentrations were statistically similar. The plasma levels of natriuretic peptides (NT-proANP, ANP and BNP) did not change during the test, and the concentrations were independent of the sodium diet. To conclude, acutely increased sodium intake does not change blood pressure or hormonal responses in a cold pressor test in young healthy subjects.