Purpose: Stone extraction is an important treatment option when performing flexible ureteroscopic lithotripsy (f-URSL) for upper urinary stones. We used a f-URSL simulator model to investigate surgical factors affecting the efficacy of stone extraction with the one-surgeon basketing technique. Materials and Methods: This simulator-based study involved eight urologists and eight residents. These participants each performed two tasks, with Flexor (Cook Medical) and Navigator (Boston Scientific) ureteral access sheaths, with and without the M-arm (MC Medical) single-use basket holder, and with models representing both left and right kidneys. The two tasks were to touch each renal calix with the ureteroscope, and to extract stones. As outcomes, we recorded the number of times that the ureteroscope became stuck during insertion, the number of times a stone was dropped during removal, the number of times the basket forceps were opened and closed, and the time required to accomplish each task. Results: The ureteroscope became stuck significantly more often when Navigator was used compared with Flexor overall, and for both urologists and residents (all p<0.01). Stones were dropped significantly more often on the ipsilateral side (kidney on the same side as the operator’s hand) than on the contralateral side overall (p=0.01), and the basket forceps were opened and closed significantly more often on the ipsilateral side than on the contralateral side both overall and by residents (all p<0.01). Conclusions The efficiency of stone extraction during f-URSL with the one-surgeon basketing technique was affected by differences in ureteral access sheath and the kidney side.

To investigate the factors affecting the rate of improvement in endurance exercise performance following pre-cooling with ice slurry, we focused on individual physical characteristics and thermoregulatory capacity. Twenty-four healthy adults (12 males and 12 females) ingested 7.5g kg-1 of either ice slurry at -1°C (ICE) or control water at 20°C (CON) before cycling at 55% VO2max and continued cycling until the rectal temperature reached 38.5°C or untill exhaustion in a hot environment (controlled at 38°C, 40% relative humidity). The relationship between the rate of improvement in exercise performance and physical characteristics and thermoregulatory factors (changes in rectal temperature, the rate of rectal temperature increase, whole body sweat loss, mean metabolic heat production, and heat storage) was investigated. No correlation was noted between the rate of improvement in exercise performance and physical characteristics and heat storage. On the other hand, the rate of improvement in exercise performance showed significant correlations with changes in rectal temperature (r = -0.497), the rate of rectal temperature increases during exercise (r = -0.784), whole body sweat loss (r = 0.407), and mean metabolic heat production (r = -0.436). The rate of inhibition of sweating and the rate of increase in metabolic heat production by ice slurry ingestion during exercise have been suggested to be related to the rate of improvement in exercise performance. On the other hand, there was no relationship between body composition or VO2max and the rate of improvement in exercise performance.

Several studies have reported that molecular hydrogen (H₂) acts as a therapeutic medical gas owing to scavenging reactive oxygen species (ROS). However, little is known about effects of H₂ on exercise-induced oxidative stress. The purpose of this study was to investigate the effects of weekly hydrogen bathing on exercise-induced oxidative stress and delayed-onset muscle soreness (DOMS). Nine healthy and active young men participated in this study, and each subject performed hydrogen bathing trial and placebo bathing trial in a crossover design. The subjects performed downhill running (8 % decline) at 75 % peak oxygen uptake (VO₂peak) for 30 min, and each subjects conducted hydrogen or placebo bathing for 20 min, respectively, 1-6 days after downhill running. Before and after exercise, we measured visual analogue scale (VAS) and collected blood samples (Pre- and 5 min, 60 min after the end of bathing, 1day, 2days, 3days, 7days after downhill running). Blood sample analyses include creatine kinase (CK), myoglobin (Mb), malondialdehyde (MDA), reactive oxygen metabolites (d-ROMs), biological antioxidant potential (BAP), myeloperoxidase (MPO), interleukin-6 (IL-6), interleukin-17a (IL-17a) and lactate concentrations. Weekly hydrogen bathing had no effects of exercise-induced oxidative stress and muscle damage. On the other hand, hydrogen bathing significantly reduced DOMS (VAS) 1 and 2days after downhill running (p=0.033). These findings suggest that hydrogen bath after downhill exercise can be effective for reduction of DOMS.

Evidence from Western countries suggests that built environmental attributes can influence the physical activity participation in adults, but whether or not this is the case for Chinese is unknown. Also, the strength of the relationship of environment to physical activity may differ by age group. The present study examined age-related differences in associations between perceived neighborhood environment and walking in Chinese women dwelling in Beijing. Cross-sectional data were collected through an internet-based survey. Total of 737 women aged 30 to 59 years responded. All of them were then divided into three groups based on the age: aged from 30-39, from 40-49 and from 50-59. In addition to socio demographic information, the perceived neighborhood environment was measured by Neighborhood Environment Walkability Scale Questionnaire, and their walking time per week was collected through International Physical Activity Questionnaire. To measure relationship between perceived neighborhood environment and walking time, partial correlations were computed, adjusting for socio demographics. Walking time was significantly related to residential density in aged 40-49 years, and land use mix-access, walking/cycling facilities, traffic safety variables in aged 50-59 years. The present study indicates that there would be differences in associations between neighborhood attributes by age-groups. Future, public health promotion of walking activity and the design of interventions need to consider the contribution of neighborhood level built environment influences.

Porpose: Physical inactivity is a modifiable risk factor for many chronic diseases. In China, inactive lifestyle is increasing yearly on Chinese adults by rapid economic development which produces their lifestyle changes. Thus, we investigated the prevalence and socio-demographic correlates of meeting the physical activity recommendation among Chinese adult internet users.Methods: Data were analyzed for 1394 Chinese adults who responded an internet based cross-sectional survey. The International Physical Activity Questionnaire Chinese version was used to determine whether the individuals met the physical activity recommendation (150minutes/week) on the ACSM/AHA guideline. Demographic data (gender, age, marital status, employment status, educational level, annual income level, and body mass index) were also obtained. A multivariate logistic regression analysis was utilized.Results: Overall, 87.3% of respondents met the physical activity recommendation. Age and annual income were significantly associated with meeting the physical activity recommendation. Women aged 40-49 years were more likely to meet the physical activity recommendation than those aged 30-39 years (OR = 2.12). Women with annual incomes of 40000∼50000 Yuan were more likely to meet the physical activity recommendation than those with annual incomes of 30000 Yuan or less (OR = 2.40).Conclusion: The high prevalence rate and different socio-demographic correlates of meeting physical activity recommendation were observed among Chinese adults compared with these in developed countries. Specific strategies accounting for such socio-demographic correlates may be needed for effectively promoting physical activity among Chinese adults.

Athletes have been instructed to refrain from taking carbonated beverages in the sports world, but the mechanism has not been clear. The purpose of this study was to clarify how physiological and biochemical evaluation are affected by taking a 10% CHO carbonated beverage after cycle ergometer (60 min, 60% VO₂max). Seven subjects consumed a carbonated or noncarbonated (10% carbohydrate) beverage after exercise. No differences were observed in concentration of glucose, insulin, free fatty acids, K and Na in serum from carbonated beverage compared with noncarbonated beverage intakes after exercise.These results indicate that carbonated beverage did not affect the changes of physiological and biochemical parameter after prolonged exercise, and it could be more refreshing and stimulate taste rather than noncarbonated beverage, but seemed to be hard to drink immediately after exercise because it made subjects feel as if having drunk more than they did.

The purpose of this study was to compare the thigh muscle oxygenation state of competitive road cyclists and non-cyclists during varied pedaling frequency cycling. Six male college road cyclists (CY group) and five male students (NC group) performed four sets of cycling bouts, consisting of 2 minutes of warm up (60 rpm, 50 watts) followed by 5 minutes of pedaling (150 watts) using an electro-magnetic braked cycle ergometer at 40, 60, 90, and 120 rpm. Oxygenated hemoglobin and/or myoglobin (Oxy-Hb/Mb) and deoxygenated Hb/Mb (Deoxy-Hb/Mb) concentrations in the vastus lateralis were measured by near infrared spatially resolved spectroscopy. The Oxy-Hb/Mb level was significantly higher in the CY group than the NC group. But there was no significant intraction effect of the group and pedaling rate on the Oxy-Hb/Mb level. These results suggest that the changes in muscle oxygenation state according to pedaling cadence do not differ between cyclists and non-cyclists. And though the whole body work efficiency decreased according to increasing pedaling cadence, Oxy-Hb/Mb and Deoxy-Hb/Mb levels in the vastus lateralis remained unchanged up to 90 rpm. However, at 120 rpm, the Oxy-Hb/Mb level decreased remarkably and the Deoxy-Hb/Mb level increased. These results suggest that deoxygenation in the vastus lateralis at 120 rpm was higher than that for lower frequencies. And, conversely, oxygen uptake in the vastus lateralis might have increased steeply at 120 rpm. It may be that the maximum pedaling cadence that would not reduce work efficiency in the vastus lateralis is around 90 rpm.

The purpose of this study was to examine the effect of class walking on lifestyle activity. The subjects were recruited from the community around the university, and volunteered to eight weeks intervention. The intervention groups were 2 different walking program groups that included a class-walking group (A : n=32) and a voluntary walking group (B : n=31) ; and the control was a blood-pressure monitor group (C : n=22) . Only A group participated in a walking class with group instruction. Physical activity was measured by pedometer counts before the start of the intervention, during the 8-week intervention and again as follow up four months afterwards. In A group, the number of pedometer counts, during the group walking activity of the 5 th and 6 th weeks, was measured in order to evaluate the number of voluntary steps on the class-walking day. Although there was no significant difference among the three groups in daily activity before the intervention, the activity of A group (12367±3290) and B group (9988±3461) was significantly increased during the intervention. Also, there were significant differences between A and B, A and C. As for A group, the number of steps due to group walking (9025±584 steps) enhanced the daily activity on the class-walking days (16191±3988 steps), but significantly attenuated the voluntary steps on the class-walking days (7166±3988 steps), which did not significantly differ from the baseline of the daily activity. The number of steps on the non-class walking days (i. e. steps other than those taken on the class-walking day ; 11719±3454 steps) was not significantly different than that of B. There was significant enhancement of daily activity 4 months after the intervention for A (11487±4057) and B (9564±2545 steps), but not for C (9070±3485 steps), compared to the baseline. There was not a significant difference between the daily activity of A and B after the intervention. These data suggest that the instruction given and the steps taken in class walking enhance daily activity during the intervention period, and that voluntary steps play a more important role in whether or not one remains active and adheres to regular exercise.

The purpose of this study was to examine the effect of fructose ingestion on maximal exercise performance capacity following prolonged steady-state exercise compared with glucose or placebo ingestion, in 7 male college students (age 23.3±0.7 yr, height 171.3±1.9 cm, weight 68.4±1.4 kg, Vo2max 3.5±0.2 L/min, mean ± SEM) . The subjects cycled constantly on an ergometer at 59± 2 % Vo2max for 100 min divided in the middle by a 5-min rest, and then performed 10 min of all-out self-paced cycling. They ingested either 8 % fructose solution (F), 8 % glucose solution (G) or artifi-cially sweetened placebo (P) before and during exercise (at 20, 40, 65, 85 mm) . Before exercise and at 50 and 100 min of exercise and 5 min after the performance ride, blood samples were collected for determination of the concentrations of blood lactate, serum glucose and serum FFA. In the G trial, the serum FFA level was significantly lower than in the P and F trials at any of the time points dur-ing and after exercise (vs. P ; p<0.01, vs. F ; p<0.05) . However, glucose ingestion maintained serum glucose at a significantly higher level during and after exercise than placebo ingestion (p< 0.01) and improved the total work output in the 10-min performance ride (G vs. P ; 135± 8 KJ vs. 128± 8 KJ, p<0.05) . Although in the F trial, the serum FFA level was elevated during exercise compared to that in the G trial and the serum glucose level was significantly higher than in the P trial (vs. P ; p<0.01), the blood lactate level after exercise was lower than in the G trial and total work output was similar to that in the P trial (123± 8 KJ, vs. G ; p<0.01) . These results indicate that fructose ingestion before and during exercise cannot improve the ability to perform high-intensity exercise late in prolonged exercise despite maintaining the serum glucose level.