The Synergetic Effect of Plyometric Compound Exercises and Transcranial Direct Current Stimulation on Balance and Physical Function.

This study aimed to investigate the effects of plyometric compound exercises and Transcranial Direct Current Stimulation (tDCS) on balance and body function in healthy adults. Forty-five students enrolled at Noryangjin Y Academy in Seoul who met the research criteria were equally and randomly divided into the following groups: the Experimental Group I, Experimental Group II, and Control Group. Experimental Groups I and II received tDCS and sham tDCS for 20 min, respectively; both groups performed plyometric compound exercises for 30 min twice weekly for four weeks. The Control Group received sham tDCS for 20 min twice weekly for four weeks. Tests such as the static balance test (Functional Reach Test, FRT), dynamic balance test (Y-Balance Test, Y-BT), power test (vertical jump test and long jump test), and agility test (t-test and side-step test) were conducted on the day of the experiment, before and after the intervention. Experimental Groups I and II significantly improved in static balance, dynamic balance, power, and agility (p < 0.001), whereas the Control Group did not. Experimental Group I showed greater effects on static balance, dynamic balance, power, and agility than Experimental Group II and the Control Group (p < 0.001). In conclusion, plyometric compound exercises + tDCS intervention can be effective for an ordinary person who trains balance and body functions (power and agility); in particular, to improve exercise performance.

Risk factors of repeated falls in the community dwelling old people.

This study aimed to provide evidence for the development of an algorithm to identify older adults with a high risk for repeated falls, along with strategies to prevent repeated falls, by analyzing the known physical, psychological, and environmental factors related to falls in older adults. One hundred fifty-seven community-dwelling older adults aged 65 years or older who experienced a fall within the past year were enrolled in this study. Participants' physical, psychological, environmental, and fall prevention-related characteristics were surveyed using structured questionnaires to identify the risk factors for repeated falls. The use of antidepressants, depression score, and compliance with fall prevention behaviors were found to differ significantly between the two groups, and the use of antidepressants and depression were found to be significant predictors of repeated falls. Depression should be considered as a major variable when developing an algorithm to identify the risk of repeated falls among older adults living at home. Also, the practice of fall prevention behaviors was higher in the repeated-falls group, likely due to that group's efforts to prevent additional falls.

Effect of the combined isotonic technique for proprioceptive neuromuscular facilitation and taping on pain and grip strength in patients with lateral epicondylitis: a randomized clinical trial.

The purpose of this study was to investigate the effect of the combined isotonic technique (CIT) for proprioceptive neuromuscular facilitation and taping intervention on pain and grip strength in patients with lateral epicondylitis (LE). Twenty subjects with LE were treated 5 times a week for 4 weeks. Patients were randomized to an experimental group (n=10) with taping after CIT and a control group (n=10) with taping after stretching. A visual analogue scale (VAS) was used to measure changes in pain. A hand dynamometer was used to measure grip strength. A paired t-test was performed to compare differences after the intervention. We used an independent t-test to compare the differences between experimental and control groups. All statistical significance levels were set at α=0.05. Within-group changes in VAS and grip strength were significantly different in both the experimental and control groups (P<0.05). Between-groups after intervention, VAS and grip strength showed more improvement in the experimental group than in the control group (P<0.05). This study showed that by applying CIT and taping to patients with LE, significant improvement in pain and grip strength could be obtained. Since the intervention had positive effects on LE by reducing pain and increasing grip strength, additional studies on efficient intervention will be conducted to develop exercise programs.

Effects of Music Therapy on the Cardiovascular and Autonomic Nervous System in Stress-Induced University Students: A Randomized Controlled Trial.

OBJECTIVE: Stress is caused when a particular relationship between the individual and the environment emerges. Specifically, stress occurs when an individual's abilities are challenged or when one's well-being is threatened by excessive environmental demands. The aim of this study was to measure the effects of music therapy on stress in university students. DESIGN: Randomized controlled trial. PARTICIPANTS: Sixty-four students were randomly assigned to the experimental group (n = 33) or the control group (n = 31). INTERVENTION: Music therapy. OUTCOME MEASURES: Initial measurement included cardiovascular indicators (blood pressure and pulse), autonomic nervous activity (standard deviation of the normal-to-normal intervals [SDNN], normalized low frequency, normalized high frequency, low/high frequency), and subjective stress. After the first measurement, participants in both groups were exposed to a series of stressful tasks, and then a second measurement was conducted. The experimental group then listened to music for 20 minutes and the control group rested for 20 minutes. A third and final measurement was then taken. RESULTS: There were no significant differences between the two groups in the first or second measurement. However, after music therapy, the experimental group and the control group showed significant differences in all variables, including systolic blood pressure (p = .026), diastolic blood pressure (p = .037), pulse (p < .001), SDNN (p = .003), normalized low frequency (p < .001), normalized high frequency (p = .010), and subjective stress (p = .026). CONCLUSION: Classical music tends to relax the body and may stimulate the parasympathetic nervous system. These results suggest music therapy as an intervention for stress reduction.

What is more damaging to vascular endothelial function: Diabetes, age, high BMI, or all of the above?

BACKGROUND: It is well established that there is a reduction in the skin blood flow (SBF) in response to heat with age and diabetes. While it is known that high BMI creates a stress on the cardiovascular system and increases the risk of all cause of morbidity and mortality, little is known of the effect of high BMI on SBF response to heat. Since diabetes is associated with age and a higher BMI, the interrelationship between age, BMI and SBF needs to be investigated to better understand the contribution diabetes alone has to endothelial impairment. MATERIAL AND METHODS: This study examined the SBF to heat in young and old people with low and high BMI and people with diabetes with high BMI to determine the contribution these variables have on SBF. Subjects were ten young and older people with BMI <20 and ten young and older people with BMI >20 and ten subjects with diabetes with BMI >20. The SBF response, above the quadriceps, was determined during a 6 minutes exposure to heat at 44°C. RESULTS: Even in young people, SBF after the stress of heat exposure was reduced in subjects with a high BMI. The effect of BMI was greatest in young people and lowest in older people and people with diabetes; in people with diabetes, BMI was a more significant variable than diabetes in causing impairment of blood flow to heat. BMI, for example, was responsible for 49% of the reduction in blood flow after stress heat exposure (R=-0.7) while ageing only accounted for 16% of the blood flow reduction (R=-0.397). CONCLUSIONS: These results would suggest the importance of keeping BMI low not only in people with diabetes to minimize further circulatory vascular damage, but also in young people to diminish long term circulatory vascular compromise.

Electroencephalography to assess motor control during balance tasks in people with diabetes.

BACKGROUND: Balance is sensed through peripheral and central receptors and mediated by central control through the brain and spinal cord. Although some evidence exists as to the areas of the brain involved and how processing of data occurs in young individuals, nothing has been published on people with diabetes. The purpose of this study was to examine the electroencephalogram (EEG) during common sensorimotor and balance training tasks and to relate these to task difficulty. SUBJECTS AND METHODS: Postural sway and EEG change of alpha, beta, and sigma wave bands were measured in 17 young subjects, 10 older subjects, and 10 subjects with diabetes during eight progressively more difficult balance tasks with eyes open and closed, feet in tandem or apart, and on foam or a firm surface. RESULTS: EEG power of beta and sigma wave bands showed significant increases on the cortical and parietal areas of the brain relative to the control tasks when eyes were open (P<0.05). The cortical involvement decreased as the task became more difficult with vision and somatosensory information reduced, whereas that of the parietal area increased with task difficulty. The greatest increase was in subjects with diabetes, and the least was in younger people. Individuals with diabetes had increased sigma and beta EEG power in all regions of the brain examined with increased complexity of the balance task. CONCLUSIONS: This study demonstrated cortical and parietal involvement in static balance tasks commonly used in sensorimotor training. The results support the proposal that there was increased subcortical control with increase in task difficulty in the young subjects, but in subjects with diabetes, there was a major increase in activity across the brain.

The interrelationship between air temperature and humidity as applied locally to the skin: the resultant response on skin temperature and blood flow with age differences.

BACKGROUND: Most studies of the skin and how it responds to local heat have been conducted with either water, thermodes, or dry heat packs. Very little has been accomplished to look at the interaction between air humidity and temperature on skin temperature and blood flow. With variable air temperatures and humidity's around the world, this, in many ways, is a more realistic assessment of environmental impact than previous water bath studies. MATERIAL/METHODS: Eight young and 8 older subjects were examined in an extensive series of experiments where on different days, air temperature was 38, 40, or 42°C. and at each temperature, humidity was either 0%, 25%, 50%, 75%, or 100% humidity. Over a 20 minute period of exposure, the response of the skin in terms of its temperature and blood flow was assessed. RESULTS: For both younger and older subjects, for air temperatures of 38 and 40°C., the humidity of the air had no effect on the blood flow response of the skin, while skin temperature at the highest humidity was elevated slightly. However, for air temperatures of 42°C., at 100% humidity, there was a significant elevation in skin blood flow and skin temperature above the other four air humidity's (p<0.05). In older subjects, the blood flow response was less and the skin temperature was much higher than younger individuals for air at 42°C. and 100% humidity (p<0.05). CONCLUSIONS: Thus, in older subjects, warm humid air caused a greater rise in skin temperature with less protective effect of blood flow to protect the skin from overheating than is found in younger subjects.

The effect of moist air on skin blood flow and temperature in subjects with and without diabetes.

BACKGROUND: Endothelial function is known to be impaired in response to heat in people with diabetes, but little has been done to see how air humidity alters the skin blood flow response to heat. METHODS: Seventeen male and female subjects were divided in two groups, one with type 2 diabetes and the other the control subjects without diabetes, age-matched to the diabetes group. All subjects participated in a series of experiments to determine the effect of the warming of the skin by air on skin temperature and skin blood flow. On different days, skin temperature was warmed with air that was 38°C, 40°C, or 42°C for 20 min. Also, on different days, at each temperature, the air humidity was adjusted to 0%, 25%, 50%, 75%, or 100% humidity. Skin blood flow and temperature were measured throughout the exposure period. This allowed the interactions between air humidity and temperature to be assessed. RESULTS: For the control subjects, the moisture in the air had no different effect on skin blood flow at air temperatures of 38°C and 40°C (analysis of variance, P>0.05), although skin blood flow progressively increased at each air temperature that was applied. But for the warmest air temperature, 42°C, although the four lower humidities had the same effect on skin blood flow, air at 100% humidity caused the largest increase in skin blood flow. In contrast, in the subjects with diabetes, blood flow was always significantly less at any air temperature applied to the skin than was observed in the control subjects (P<0.05), and skin blood flow was significantly higher for the two higher humidities for the two higher air temperatures. Skin temperature paralleled these findings. CONCLUSION: These data show that individuals with diabetes do not tolerate moist, warm air above 50% humidity as well as controls without diabetes.

Reduced endothelial function in the skin in Southeast Asians compared to Caucasians.

BACKGROUND: The reaction of vascular endothelial cells to occlusion and heat in Southeast Asian Indians (SAI) compared to Caucasians (C) has not been studied, although genetic differences are found in endothelial cells between the races. MATERIAL/METHODS: Ten C and Ten SAI (<35 years old) male and female subjects participated. There was no difference in the demographics of the subjects except that the SAI group had been in the United States for 6 months; C was natives to the US. Endothelial function was assessed by the response of the circulation (BF) to local heating and the response to vascular occlusion. The effects of local heat on circulation in the skin on the forearm was assessed by applying heat for 6 minutes at temperatures, 38, 40 and 42°C on 3 separate days. On different days, vascular occlusion was applied for 4 minutes to the same arm and skin blood flow was measured for 2 minutes after occlusion; skin temperature was either 31°C or 42°C. RESULTS: When occlusion was applied at a skin temperature of 31°C, the BF response to occlusion was significantly lower in the SAI cohort compared to C (peak BF C = 617 ± 88.2 flux, SAE = 284 ± 73 flux). The same effect was seen at skin temperatures of 42°C. The circulatory response to heat was also significantly less in SAI compared to C at each temperature examined (p<0.05)(for temperatures of 38, 40 and 42°C, peak blood flow for C was 374.7 ± 81.2, 551.9 ± 91.3 and 725.9 ± 107 flux respectively and 248.5 ± 86.2, 361.4 ± 104.3 and 455.3 ± 109.7 flux respectively for SAI. (p<0.05). CONCLUSIONS: Thus there seems to be big differences in these 2 populations in endothelial response to these stressors. The difference may be due to genetic variations between the 2 groups of subjects.

The interrealtionship between locally applied heat, ageing and skin blood flow on heat transfer into and from the skin.

In response to a thermal stress, skin blood flow (BF) increases to protect the skin from damage. When a very warm, noxious, heat source (44 °C) is applied to the skin, the BF increases disproportionately faster than the heat stress that was applied, creating a safety mechanism for protecting the skin. In the present investigation, the rate of rise of BF in response to applied heat at temperatures between 32 °C and 40 °C was examined as well as the thermal transfer to and from the skin with and without BF in younger and older subjects to see how the skin responds to a non-noxious heat source. Twenty male and female subjects (10 - 20-35 years, 10 - 40-70 years) were examined. The arms of the subjects were passively heated for 6 min with and without vascular occlusion by a thermode at temperatures of 32, 36, 38 or 40 °C. When occlusion was not used during the 6 min exposure to heat, there was an exponential rise in skin temperature and BF in both groups of subjects over the 6-min period. However, the older subjects achieved similar skin temperatures but with the expenditure of fewer calories from the thermode than was seen for the younger subjects (p<0.05). BF was significantly less in the older group than the younger group at rest and after exposure to each of the three warmest thermode temperatures (p<0.05). As was seen for noxious temperatures, after a delay, the rate of rise of BF at the three warmest thermode temperatures was faster than the rise in skin temperature in the younger group but less in the older group of subjects. Thus, a consequence of ageing is reduced excess BF in response to thermal stress increasing susceptibility to thermal damage. This must be considered in modelling of BF.

Effects of an exercise program on balance and trunk proprioception in older adults with diabetic neuropathies.

BACKGROUND: Diabetes is the most common cause of peripheral neuropathies. No definitive treatment for diabetic neuropathies has been reported, and very few studies have been published on the role of exercise in reducing either the symptoms or incidence of diabetic neuropathies. METHODS: This study assessed the effects of an exercise program on balance and trunk proprioception in older adults with diabetic neuropathies. Thirty-eight patients with diabetes having peripheral neuropathies were enrolled, randomized, and subdivided in two groups: an experimental group of 19 participants with diabetes (72.9 ± 5.6 years old) and a control group of 19 participants with diabetes (73.2 ± 5.4 years old). Both groups received health education on diabetes for 50 min/week for 8 weeks. The experimental group practiced an additional balance exercise program for 60 min, two times a week. The exercise training was performed two times per week for 8 weeks. Results were evaluated by both static and dynamic balance and trunk proprioception. RESULTS: Postural sway significantly decreased (P < 0.05), the one-leg stance test significantly increased (P < 0.05), and dynamic balance from the Berg Balance Scale, Functional Reach Test, Timed Up and Go test, and 10-m walking time improved significantly after balance exercise (P < 0.05). Trunk repositioning errors also decreased with training (P < 0.05). CONCLUSION: The balance exercise program improved balance and trunk proprioception. These results suggested that a balance exercise is suitable for individuals with diabetic neuropathy.

The ability of different areas of the skin to absorb heat from a locally applied heat source: the impact of diabetes.

BACKGROUND: When heat is applied to the skin, heat is conducted away because of the latent heat transfer properties of the skin and an increase in skin circulation, but little attention has been paid to the heat transfer properties of skin in different areas of the body and in people with diabetes. research design: Thirty subjects in the age range of 20-75 years had a thermode (44°C) applied to the skin of their arm, leg, foot, and back for 6 min to assess the heat transfer characteristics of skin in these four areas of the body. Skin blood flow and skin temperature were monitored over the 6-min period. RESULTS: For the younger subjects, blood flow was not statistically different in response to heat in three areas of the body, starting at less than 200 flux measured by a laser Doppler imager and ending at approximately 1,200 flux after heat exposure. The foot had higher resting blood flow and higher blood flow in response to heat. Temperature and the rate of rise of temperature were also not different in any of the areas. The heat added to raise temperature, however, varied by body region. The arm required the least, whereas the leg and foot required the most. For the older group and subjects with diabetes, the heat required for any region of the body was much less to achieve the same increase in skin temperature, and blood flows were also much less; the subjects with diabetes showed the least blood flow and required the fewest calories to heat the skin. Whereas the foot required the greatest number of calories to heat the tissue in younger and older subjects, in subjects with diabetes, the foot took proportionally fewer calories. CONCLUSION: Thus, specific areas of the body are damaged more by diabetes than other areas.

The contribution of skin blood flow in warming the skin after the application of local heat; the duality of the Pennes heat equation.

As predicted by the Pennes equation, skin blood flow is a major contributor to the removal of heat from an external heat source. This protects the skin from erythema and burns. But, for a person in a thermally neutral room, the skin is normally much cooler than arterial blood. Therefore, if skin blood flow (BF) increases, it should initially warm the skin paradoxically. To examine this phenomenon, 10 young male and female subjects participated in a series of experiments to examine the contribution of skin blood flow in the initial warming the skin after the application of local heat. Heat flow was measured by the use of a thermode above the brachioradialis muscle. The thermode was warmed by constant temperature water at 44°C entering the thermode at a water flow rate of 100 cm(3)/min. Skin temperature was measured by a thermistor and blood flow in the underlying skin was measured by a laser Doppler imager in single point mode. The results of the experiments showed that, when skin temperature is cool (31-32°C), the number of calories being transferred to the skin from the thermode cannot account for the rise in skin temperature alone. A significant portion of the rise in skin temperature is due to the warm arterialized blood traversing the skin from the core areas of the body. However, as skin temperature approaches central core temperature, it becomes less of a heat source and more of a heat sync such that when skin temperature is at or above core temperature, the blood flow to the skin, as predicted by Pennes, becomes a heat sync pulling heat from the thermode.

The influence of aging and diabetes on heat transfer characteristics of the skin to a rapidly applied heat source.

BACKGROUND: Numerous studies have examined the blood flow of the skin at rest and in response to sustained heat and shown that, in older people and people with diabetes, the skin blood flow response to heat is diminished compared to younger people. It is not sustained heat, however, that usually causes burns; it is a more rapid application of heat. SUBJECTS AND METHODS: Ten younger subjects, 10 older subjects, and 10 subjects with diabetes were examined before and after applying a water-filled thermode to the skin above the quadriceps muscle to observe the changes in skin temperature and skin blood flow and the ability of the skin to absorb heat after a 2-min heat exposure with water at 44°C. RESULTS: Skin temperature rose from 31.2°C at rest to 38.3°C after 2 min of heat application in all subjects (P > 0.05 between groups). The calories required in the younger group of subjects was 2.26 times the calories required in the older group of subjects for the same change in skin temperature and 13.8 times the calories needed to increase skin temperature in the subjects with diabetes. Furthermore, the blood flow at rest was lower in people with diabetes than older subjects and both groups less than that seen in younger subjects. The blood flow response to heat was slower in the subjects with diabetes compared to the older subjects and much slower than that seen in the younger subjects. CONCLUSIONS: Reduced skin blood flow of older and subjects with diabetes, decreased thickness of the dermal layer, and increased subcutaneous fat, as well as damage to transient receptor potential vanilloid 1 receptors, may account for some of the differences between the groups.