Training Session and Detraining Duration Affect Lower Limb Muscle Strength Maintenance in Middle-Aged and Older Adults: A Systematic Review and Meta-Analysis.

Muscle strength after detraining is still higher than the level before training, which is an important issue for middle-aged and older adults. The purpose of the present study was to examine the effects of detraining duration (DD), resistance training duration (RTD), and intensity on the maintenance of resistance training (RT) benefits after detraining in middle-aged and older adults. A systematic search yielded 15 randomized control trails (n = 383) eligible for inclusion. The results showed that RTD ≥ 24 weeks and DD ≥ RTD, the RT benefits were still significantly maintained even with medium and low intensity (standardized mean difference = 1.16, 95% confidence interval, CI [0.38, 1.94], p = .004). When RTD < 24 weeks and DD ≤ RTD, only the high-intensity groups maintained the RT benefits (DD, 4-6 weeks: standardized mean difference = 0.71, 95% CI [0.34, 1.08], p = .0002; DD 8-16 weeks: standardized mean difference = 1.35, 95% CI [0.66, 2.04], p = .0001). However, when DD > RTD, the RT benefits were not maintained even with high intensity. In summary, when RTD was less than 24 weeks, RTD > DD was an important factor in maintaining muscle strength.

A community-based approach to lean body mass and appendicular skeletal muscle mass prediction using body circumferences in community-dwelling elderly in Taiwan.

BACKGROUND AND OBJECTIVES: To develop and validate the prediction equations for lean body mass (LBM) and appendicular skeletal muscle mass (ASM) using body circumference measurements of community-dwelling adults older than 50 years old. METHODS AND STUDY DESIGN: Four hundred and ninety-eight community-dwelling adults older than 50 years old were recruited for this study. Participants were randomly assigned to a development group (DG, n=332) and validation group (VG, n=166). Lean body mass and ASM were assessed using dualenergy x-ray absorptiometry along with the anthropometric parameters. The Pearson correlation coefficient was used to examine the associations between ASM, LBM and anthropometric parameters in the DG. Prediction equations for LBM and ASM were established from DG data using multiple regression analyses. Paired t-test and Bland-Altman test were used to validate the equations in the VG. RESULTS: Forearm circumference had the highest correlation with LBM and ASM. The developed prediction models were: LBM (kg) = 27.479 + 0.726 * weight (kg) - 3.383 * gender (male = 1, female = 2) - 0.672 * BMI + 0.514 * forearm circumference (cm) - 0.245 * hip circumference (cm)(r2=0.90); ASM (kg) = -4.287 + 0.202 * weight (kg) - 0.166 * hip circumference (cm) - 1.484 * gender (male = 1, female = 2) + 0.173 * calf circumference (cm) + 0.096 * height + 0.243 * forearm circumference (cm)(r2=0.85). CONCLUSIONS: Prediction equations using only a measuring tape provide accurate, inexpensive, practical methods to assess LBM and ASM in Asians older than 50 years old.

Effects of land vs water jump exercise: Implications for exercise design targeting bone health.

PURPOSE: To quantify ground reaction force (GRF), osteogenic index (OI), muscle activity, and blood lactate levels during continuous jumping performed in water and on land. METHODS: Thirteen post-menopausal women (59.5 ± 6.8 years) performed two bouts of jumping, on land (LND) and in water at a depth of 1 m (WEX). Each 10-minute, 40-second bout consisted of 2 consecutive sets of squat, lunge, jumping jax, countermovement, and single legged jumps as intervals: 10 seconds maximal effort and 60 seconds recovery at 50% of heart rate reserve (HRR). Pre- and post-exercise lower extremity rate of perceived exertion (RPE) was recorded, and 10-µL earlobe blood samples were collected to assess lactate concentration. During exercise, data were collected for electromyography, GRF, and heart rate. Total GRF (TGRF) and total muscular activity (TMA) during each 10 seconds of jumping were measured. OI for one bout of continued jumps was determined by averaging GRF·ln (number of jumps + 1). RESULTS: There were no differences between WEX and LND for percent HRR and RPE. TGRF, OI, TMA, and lactate concentration on LND jumps were significantly higher than WEX. CONCLUSION: At similar cardiorespiratory and RPE levels, the lower impact loading of 10 minutes 40 seconds of interval continuous jumping exercise in 1-m depth was less osteogenic than on land. However, one daily bout of water jumping, 5 days per week resulted in a similar OI as 3 days of jumping on land. WEX might substitute or provide an adjunct to LND exercise to promote bone health.

Effects of Dynamic Stretching with Different Loads on Hip Joint Range of Motion in the Elderly.

The purpose of this study was to investigate the immediate and sustained effects of static stretching (SS), dynamic stretching (DS) with no-load (DSNL), DS with a light load (DSLL, 0.25 kg), and DS with a heavy load (DSHL, 0.5 kg) on the hip joint range of motion (ROM). Sixteen participants (63.2 ± 7.13 years) were randomly assigned to perform SS, DSNL, DSLL, and DSHL exercises. The ROM for passive flexion and extension of the right hip joint was measured at pretest, as well as immediately after and at 60 min after completing the exercise. Additionally, the ROM of hip flexion and extension during the stretching exercise was evaluated by kinematic analysis of video-captured images. Passive ROM measurements reveals that the hip flexion ROM was higher after DSNL than after DSLL and DSHL at both time points (DSNL vs. DSLL, DSHL: 0 min: 7.0% vs. -1.8%, -3.9%; 60 min: 7.8% vs. -2.1%, -1.4%, p < 0.05), as well as higher than after SS at 60 min after exercise (DSNL vs. SS: 7.8% vs. 1.0%, p < 0.05). Compared to SS, all types of DS demonstrated a more sustained effect of ROM improvement at 60 min (DSNL, DSLL, DSHL vs. SS: 8.0%, 5.6%, 7.0% vs. 1.6%, p < 0.05). These results suggest that all DS modes can effectively improve hip extension ROM in the elderly. DSNL may be the most effective exercise for improving hip flexion ROM, providing sustained effect for over 60 min.

Neuromuscular Activity and Muscular Oxygenation Through Different Movement Cadences During In-water and On-land Knee Extension Exercise.

Chien, K-Y, Kan, N-W, Liao, Y-H, Lin, Y-L, Lin, C-L, and Chen, W-C. Neuromuscular activity and muscular oxygenation through different movement cadences during in-water and on-land knee extension exercise. J Strength Cond Res 31(3): 750-757, 2017-The purpose of this study was to determine the influence of various knee extension exercise cadences on neuromuscular activation and hemodynamic properties of the quadriceps muscle in water and on land. Seventeen young women participated in this study, and the subjects were randomly allocated to perform loaded knee extension exercises in water and on land at 4 different cadences of 30, 50, 70, and 90 b·min. Heart rate (HR), blood flow (BF), total saturation index (TSI) of oxygen, electromyography (EMG) for the extent of muscular activity, and rate of perceived exertion (RPE) were measured. Response values of HR, BF, TSI, and RPE at each cadence were obtained by subtracting the resting values from the indicator values measured at the respective cadences. We observed that BF, EMG, and RPE in water at 90 b·min were comparable with those on land. The HR and TSI changes were higher in water compared with on land (p = 0.004 and p = 0.013, respectively). In conclusion, we demonstrate that the neuromuscular activity when performing knee extension exercises at 90 b·min in water was comparable with that on land. However, exercising in water at the same cadence evoked higher TSI responses and greater cardiovascular challenges. A knee extension exercise at 90 b·min is the recommended operating speed of rehabilitation in water.

High-protein diet with immediate post-exercise protein drink: Impact on appetite in middle-aged obesity.

Successful management of obesity can be challenging if individuals constantly experience cravings. The present study investigated the effects of a high-protein diet, including a high-protein drink consumed immediately after high-intensity interval training (HIIT), on appetite and weight loss in obese middle-aged individuals. A total of 52 obese middle-aged individuals (58.2 ± 4.11 years old) were randomly assigned to one of three groups: the exercise group (E, n=19), exercise and high-protein diet group (ED, n=21), and a control group (n=12). The E and ED groups engaged in cycling HIIT (comprising 90 % of peak heart rate (HRpeak) for 3 min, followed by 70 % of HRpeak for 3 min, for a total of 5 cycles) three times a week for 3 months. The ED group consumed a high-protein drink immediately after HIIT and had a daily protein intake of 1.6g/kg. Body composition and eating behavior were assessed before and after the intervention. Additionally, appetite levels were measured before and after each exercise session, before dinner, and before bedtime during three phases of the intervention: the first phase (weeks 3-4), the second phase (weeks 5-8), and the third phase (weeks 9-12). Results showed that only the ED group experienced a decrease in body mass index (from 27.4 ± 4.28 to 26.8 ± 4.09 kg/m2, p=0.04). Appetite significantly increased after exercise in both E and ED groups (p values for the three phases ranged from 0.04 to 0.001 for the E group and from 0.042 to 0.003 for the ED group). The desire to eat significantly increased after exercise in the E group (phase 1: p = 0.026; phase 2: p = 0.011; phase 3: p = 0.003), but not in the ED group. Furthermore, the frequency of late-night snacking decreased in the ED group (the score changed from 2.4 ± 0.86 to 2.7 ± 0.80, p = 0.034). Notably, the E group tended to have a higher pre-dinner appetite score than the ED group in the third phase (p = 0.063). In summary, a high daily protein intake, combined with the consumption of high-protein drinks after exercise, resulted in reduced post-exercise appetite and a decrease in the frequency of late-night snacking.

Use of Chinese Herbal Medicine Was Related to Lower Risk of Osteoporotic Fracture in Sarcopenia Patients: Evidence from Population-Based Health Claims.

Introduction: With population aging, sarcopenia and its accompanying risk of osteoporotic fracture has drawn increased attention. Nowadays, while Chinese herbal medicine (CHM) is often used as complementary therapy for many medical conditions, its effect against likelihood of osteoporotic fracture among sarcopenia subjects was not fully elucidated yet. We therefore conducted a population-level study to compare osteoporotic fracture risk for sarcopenia persons with or without CHM use. Methods: Using the patient record from a nationwide insurance database, we recruited persons with newly diagnosed sarcopenia and simultaneously free of osteoporotic fracture between 2000 and 2010. Propensity score matching was then applied to randomly select sets of CHM users and non-CHM users. All of them were tracked until end of 2013 to measure the incidence and adjusted hazard ratios (HRs) for new new-onset fracture in multivariable Cox proportional hazards model. Results: Compared to non-CHM users, the CHM users indeed had a lower incidence of osteoporotic fracture (121.22 vs 156.61 per 1000 person-years). Use of CHM correlated significantly with a lower fracture likelihood after adjusting for potential covariates, and those receiving CHM treatment for more than two years experienced a remarkably lower risk by 73%. Uses of several herbal formulae were correlated to reduced risk of osteoporotic fracture, such as Caulis Spatholobi, Xuduan, Duzhong, Danshen, Shu-Jing-Huo-Xue-Tang, Du-Huo-Ji-Sheng-Tang, Shao-Yao-Gan-Cao-Tang, and Shen-Tong-Zhu-Yu -Tang. Conclusion: Our study depicted that cumulative CHM exposure was inversely associated with osteoporotic fracture risk in a duration-dependent manner, implying that CHM treatment may be embraced as routine care in preventing incident osteoporotic fracture.

Swim training reduces metformin levels in fructose-induced insulin resistant rats.

PURPOSE: Regular exercise training and metformin medication are widely considered to increase insulin sensitivity and protect against type 2 diabetes, however, evaluating the effect of exercise training on the disposition and pharmacokinetics of metformin is unclear. METHODS: We investigated the effect of a 4-wk swim training program (45 min/day, 5 days/wk) on the pharmacokinetics for the use of metformin in fructose-induced insulin resistant rats. Fructose-induced insulin resistant rats were assigned into two groups (n=6/group): swim training with metformin (SM), and non-swim training with metformin (CM). Blood samples were collected from 12 h-fasted rats at baseline and at 0.25, 0.5, 0.75, 1, 2, 3, 4, 6, 8, 10, and 12 h after an oral glucose tolerance test (OGTT) with administration of a single dose of metformin (450 mg/kg). RESULTS: Our study revealed that both glucose and insulin levels in the SM group were significantly lower than those in the CM group at 15 min following OGTT. The maximum concentration (C(max)) and area under the serum concentration-time curve (AUC) for the SM group were significantly lower than CM group. The apparent distribution volume (Vd) and the time-averaged total body clearance (CL) for the SM group were significantly higher than those for the CM group. There were no significant differences in the time to maximum concentration (T(max)) or the time to half-life concentration (t(1/2)) between the two groups. CONCLUSIONS: Our data demonstrate that swim training reduces metformin serum levels.

Accelerometer-based prediction of ground reaction force in head-out water exercise with different exercise intensity countermovement jump.

BACKGROUND: Water jumping exercise is an alternative method to achieve maintenance of bone health and reduce exercise injuries. Clarifying the ground reaction force (GRF) of moderate and high cardiopulmonary exercise intensities for jumping movements can help quantify the impact force during different exercise intensities. Accelerometers have been explored for measuring skeletal mechanical loading by estimating the GRFs. Predictive regression equations for GRF using ACC on land have already been developed and performed outside laboratory settings, whereas a predictive regression equation for GRF in water exercises is not yet established. The purpose of this study was to determine the best accelerometer wear-position for three exercise intensities and develop and validate the ground reaction force (GRF) prediction equation. METHODS: Twelve healthy women (23.6 ± 1.83 years, 158.2 ± 5.33 cm, 53.1 ± 7.50 kg) were recruited as participants. Triaxial accelerometers were affixed 3 cm above the medial malleolus of the tibia, fifth lumbar vertebra, and seventh cervical vertebra (C7). The countermovement jump (CMJ) cadence started at 80 beats/min and increased by 5 beats per 20 s to reach 50%, 65%, and 80% heart rate reserves, and then participants jumped five more times. One-way repeated analysis of variance was used to determine acceleration differences among wear-positions and exercise intensities. Pearson's correlation was used to determine the correlation between the acceleration and GRF per body weight on land (GRFVLBW). Backward regression analysis was used to generate GRFVLBW prediction equations from full models with C7 acceleration (C7 ACC), age, percentage of water deep divided by body height (PWDH), and bodyweight as predictors. Paired t-test was used to determine GRFVLBW differences between values from the prediction equation and force plate measurement during validation. Lin's CCC and Bland-Altman plots were used to determine the agreement between the predicted and force plate-measured GRFVLBW. RESULTS: The raw full profile data for the resultant acceleration showed that the acceleration curve of C7 was similar to that of GRFv. The predicted formula was - 1.712 + 0.658 * C7ACC + 0.016 * PWDH + 0.008 * age + 0.003*weight. Lin's CCC score was 0.7453, with bias of 0.369%. CONCLUSION: The resultant acceleration measured at C7 was identified as the valid estimated GRFVLBW during CMJ in water.

Effects of Acute Aquatic High-Intensity Intermittent Exercise on Blood Pressure and Arterial Stiffness in Postmenopausal Women with Different ACE Genotypes.

The present study investigated the effects of acute aquatic high-intensity intermittent jumping (HIIJ) on blood pressure (BP) and arterial stiffness in postmenopausal women with different angiotensin-converting enzyme genotypes (ACE). We recruited 12 postmenopausal women carrying the ACE deletion/deletion (DD) genotype and 61 carrying the insertion/insertion or insertion/deletion (II/ID) genotype. The participants performed 12 trials of 30 s, 75% heart rate reserve (HRR) jumping, and 60 s, 50% HRR recovery, and 3 trials of 40 s upper limb resistance exercises were performed as fast as possible. The heart rate (HR) and BP were measured before exercise, immediately, 10 min, and 45 min after exercise. The brachial-ankle pulse wave velocity (baPWV) was measured before and after exercise. The systolic blood pressure (SBP) of the DD genotype increased more significantly than those with the II/ID genotype post-exercise (30.8 ± 4.48 vs. 20.4 ± 2.00 mmHg, p = 0.038). The left and right sides of baPWV increased significantly after exercise (1444.8 ± 29.54 vs. 1473.4 ± 32.36 cm/s, p = 0.020; 1442.1 ± 30.34 vs. 1472.0 ± 33.09, p = 0.011), and there was no significant difference between the two groups. The HIIJ increased baPWV. The postmenopausal women with the DD genotype have a higher SBP increased post-exercise than those with II/ID genotype. These findings suggest that the aquatic exercise program has better effects in decreasing blood pressure in postmenopausal women with the II/ID genotype. Those with the DD genotype should pay attention to the risk of increasing blood pressure after aquatic HIIJ exercise.

Effects of BCAA, arginine and carbohydrate combined drink on post-exercise biochemical response and psychological condition.

This study investigated the effects of BCAA, arginine and carbohydrate combined beverage (BCAA Drink) on biochemical responses and psychological conditions during recovery after a single bout of exhaustive exercise. Fourteen healthy males were assigned to drink either BCAA Drink (BA trial) or placebo (PL trial) on two sessions separated by 2 weeks. Blood samples of each subject were collected before exercise, 0, 10, 20, 40, 60, 120 min and 24 h after exercise. No significant differences in the levels of lactate, ammonia, creatine kinase and glycerol between the two groups were observed at any of the time points. However, the levels of glucose and insulin were significantly higher in the BA trial as compared to those in the PL trial at the 40 and 60 min recovery points. Furthermore, the testosterone-to-cortisol ratio at the 120 min recovery point was significantly higher in the BA trial as compared to that in the PL trial. The results indicate the occurrence of anabolic response during the recovery period. The benefit of BCAA Drink was also performed by Profile of Mood States to assess the psychological condition. Fatigue score increased immediately at exhaustion in both groups, but the decrease in the fatigue score at 120 min recovery point was significant only in BA trial. These data indicate that a single bout of exhaustive exercise enhanced the feeling of fatigue. The detrimental consequence was reduced by an ingestion of BCAA Drink.

Aquatic Exercise for Health Promotion: A 31-Year Bibliometric Analysis.

The present study aimed to review the research literature on aquatic exercise for health promotion using bibliometric methods and CiteSpace software. The number of studies related to this topic are constantly expanding, with the USA, Brazil, and Australia the centers of this research. Most published papers fall within Sports Science, but the disciplines of Physiology, Psychology, and Rehabilitation were also found to be dominant domains for this literature. The seven most prolific authors were from Brazil or Spain. The most frequently cited references focused on sub-topics of physiology, biochemistry, physical fitness, psychological health, cardiovascular disease, and joint disease. New research trends have shifted to the promotion of cardiovascular health in clinical populations (stroke, overweight, hypertension, endothelium dysfunctional, obese, inflammation, antioxidant, heart failure). Overall, this review found that research hot spots and trends in this realm have focused on improving cardiovascular health with aquatic exercise.

Effects of Combined High-Protein Diet and Exercise Intervention on Cardiometabolic Health in Middle-Aged Obese Adults: A Randomized Controlled Trial.

Background: Obesity is the main risk factor of cardiovascular diseases (CVD) and metabolic diseases. The middle-aged population is the age group with the highest prevalence of obesity. Thus, improving cardiometabolic health is important to prevent CVD and metabolic diseases in middle-aged obese adults. The aim of this study was to examine the effects of exercise alone or in combination with a high-protein diet on markers of cardiometabolic health in middle-aged adults with obesity. Methods: Sixty-nine middle-aged adults with obesity were assigned randomly to the control group (C; n = 23), exercise group (E; n = 23), or exercise combined with high-protein diet group (EP; n = 23). Individuals in the E and EP groups received supervised exercise training and individuals in the EP group received high-protein diet intervention. Body composition (assessed by dual-energy X-ray absorptiometry), oral glucose tolerance test (OGTT), lipid profiles, and inflammatory markers were determined before and after 12 weeks of intervention. Insulin sensitivity index (ISI0,120) was calculated from values of fasting and 2-h insulin and glucose concentration of OGTT. Insulin-peak-time during the OGTT was recorded to reflect ß-cell function. Analysis of covariance with baseline values as covariates was used to examine the effects of the intervention. The significant level was set at 0.05. Results: After 12 weeks of intervention, the E group had a greater percentage of individuals with early insulin-peak-time during the OGTT than that in the C and EP groups (p = 0.031). EP group had lower total cholesterol and triglycerides than that in the C group (p = 0.046 and 0.014, respectively). Within-group comparisons showed that the 2-h glucose of OGTT and C-reactive protein decreased in the EP group (p = 0.013 and 0.008, respectively) but not in the E and C groups; insulin sensitivity improved in the EP group (p = 0.016) and had a trend to improve in the E group (p = 0.052); and abdominal fat mass and total body fat mass decreased in both intervention groups (p < 0.05). Conclusion: Combined high-protein diet and exercise intervention significantly decreased fat mass and improved lipid profiles, insulin sensitivity, glucose tolerance, and inflammation in middle-aged adults with obesity. Clinical Trial Registration: Thai Clinical Trials Registry, TCTR20180913003, 13-09-2018.

Sub-maximal exercise altered the prednisolone absorption pattern.

PURPOSE: Prednisolone has been widely used due to its relatively short pituitary inhibition and its moderate potency. Exercise is one of the non-pharmacological interventions for glucocorticoid- induced osteoporosis prevention. However, the effects of exercise on the pharmacokinetics of prednisolone were unclear. The purpose of this study was to evaluate the effects of sub-maximal exercise on the pharmacokinetics of prednisolone. METHODS: A randomized, double-blind, cross-over experimental design was used. Subjects needed to undertake two trials: a non-exercise trial (NE) and an exercise trial (E). After the first blood sampling, the subjects consumed 5 mg of prednisolone with 100 mL of water and then took a rest for 30 min. In the E trial, subjects cycled at 70% VO(2max) intensity until exhaustion. When subjects underwent the NE trial, they remained seated for the duration of the experiment. Serial blood samples were collected at 0.25, 0.5, 0.75, 1, 1.25, 1.5, 2, 3, 4, 5, 6, 8, 10 and 12 hr after prednisolone administration. Prednisolone and cortisol concentration were analyzed with a validated high performance liquid chromatographic method. RESULTS: This study indicated that the maximum concentration of the E trial was significantly lower than the NE trial (p<.05). However, the area under the plasma concentration-time, half life, the time-averaged total body clearance, and the apparent volume of the distribution showed no significant difference between two trials. The mean percentage change of cortisol of E trail was significantly higher than NE trail (p<.05). CONCLUSIONS: The results suggested that sub-maximal exercise altered the prednisolone absorption pattern.

Land vs. water HIIE effects on muscle oxygenation and physiological parameter responses in postmenopausal women.

Muscle oxygenation (MO) status is the dynamic balance between O2 utilization and O2 delivery. Low-impact high-intensity interval exercise MO responses in the exercise and recovery stage are still unclear. We compared the differences in MO and physiological parameters between high-intensity interval water-based exercise (WHIIE) and high-intensity interval land bike ergonomic exercise (LBEHIIE) in postmenopausal women. Eleven postmenopausal women completed WHIIE or LBEHIIE in counter-balanced order. Eight sets were performed and each exercise set included high intensity with 80% heart rate reserve (HRR) in 30 s and dynamic recovery with 50% HRR in 90 s. Muscle tissue oxygen saturation index (TSI), total hemoglobin (tHb), oxy-hemoglobin (O2Hb), and deoxy-hemoglobin (HHb) were recorded. Blood lactate, heart rate and rating of perceived exertion (RPE) were measured at pre and post-exercise. Under similar exercise intensity, RPE in WHIIE was lower than that in LBEHIIE. The heart rate in WHIIE was lower than that in LBEHIIE at 1 and 2 min post-exercise. During the dynamic recovery, TSI, tHb, and O2Hb in water were higher than on land. A negative correlation was found between the change in TSI and lactate concentration (r = - 0.664). WHIIE produced greater muscle oxygenation during dynamic recovery. Muscle TSI% was inversely related to blood lactate concentration during exercise in water.

Cold water immersion recovery strategy increases blood pressure levels after high-intensity intermittent exercise.

BACKGROUND: This study aimed to investigate the effects of cold water immersion (CWI) recovery strategies on the blood pressure levels and related physiological parameters after high-intensity intermittent exercise (HIIE). METHODS: This randomized crossover study included 20 men (21.5±1.6 years). Each participant performed a maximum-exertion exercise performance test on a bicycle, and heart rate was measured. Subsequently, six cycles of HIIE (1 minute at 120% heart rate reserve [HRR] and 4 minutes at 40% HRR) were performed in a random sequence, and the recovery period involved either CWI or static rest (SR). RESULTS: Systolic and diastolic blood pressure levels at the 6th and 20th minute of CWI recovery were significantly higher than those during SR and significantly higher than those during a quiet state at the 6th minute. The heart rates at the 20th minute and 35th minute of CWI recovery were significantly lower than that during SR, and the ratings of perceived exertion (RPE) at the 6th and 20th minute of CWI recovery were significantly lower than that during SR. No significant difference in lactate production was evident between the two recovery strategies. Ear temperature was not significantly different when it was quiet, at the end of exercise, and at the 6th and 35th minute of recovery; however, at the 20th minute of recovery, ear temperature during CWI was significantly higher than that during SR. CONCLUSIONS: CWI after HIIE reduced the extent to which blood pressure decreased. For the fatigue-related heart rate and RPE indicators, CWI was superior to SR.

Aging effects on glycemic control and inflammation for politicians in Taiwan.

UNLABELLED: Insulin sensitivity is deteriorating with age leading to many metabolic complications, yet fasting glucose is the common metabolic predictor in preventive medicine. In this study we compared the differences in fasting glucose, glucose tolerance, and inflammatory markers between two generations in politically active families. Their physical activity levels and dietary intake amounts were also evaluated. Eight elected councilors and their first order descendents participated in this study. Oral glucose tolerance test (OGTT), insulin, triglyceride, cholesterol, and inflammatory markers including C-reactive protein (CRP) and interleukin-6 (IL-6) were determined. Fasting glucose concentration in politicians was smaller than 100 mg/dL (considered clinically normal), and only approximately 14% concentration difference was observed between two generations. However, all politicians were substantially insulin resistant, compared with their young descendents, evidenced by exaggerated glucose and insulin responses (>100% greater area under curves above baseline) under oral glucose challenged condition. Their waist circumference, diastolic blood pressure, and cholesterol levels were significantly greater than controls. Furthermore, CRP of the politicians was approximately 2.3 folds of the control value suggesting a low grade inflammation. The levels of physical activity and dietary intake were not different between groups. However, the weekly walking energy expenditure for the politician group was approximately 3 times greater than that of the control. CONCLUSION: To reflect the age-dependent metabolic deterioration for the purpose of prevention, OGTT and CRP are far more sensitive measures than fasting glucose value. Greater walking activity in politicians was not sufficient to counterbalance the age-dependent changes.

Ratings of Perceived Exertion and Physiological Parameters of Muscle Metabolism in Postmenopausal Women.

We compared responses from postmenopausal women living a sedentary lifestyle ( n = 15; Mean age= 59; SD = 4.2) to a single bout of water- or land-based exercise with respect to ratings of perceived exertion (RPE), lactate concentration, and muscle oxygen saturation. Each participant was randomly assigned to a single water- or land-based 50-minute bout of combined aerobic and resistance exercise. Blood samples were collected to detect pre- and post-exercise lactate concentration. Total hemoglobin, deoxidized hemoglobin, and the percentage change in the total oxygen saturation index (TSI%) of the rectus femoris were detected by means of near-infrared spectroscopy. We found similar RPE at various stages of land- and water-based exercise, and a similar change in lactate concentration in these environments (in water: 4.35 ± 1.49 mol/L; on land: 3.62 ± 1.18 mol/L). However, the reduction in HHb response was less pronounced after water-based exercise, and TSI% increased on land but decreased in water, with the magnitude of this change much higher on land. For similar RPE and lactate concentration, the oxygen saturation in the exercising muscles decreased in water, suggesting higher oxygen consumption in water than on land.

Glucose tolerance and insulin sensitivity following an one-week volleyball competition.

The purpose of the study was to compare glucose tolerance and insulin sensitivity between trained (TR) and competition (CP) states, in relation to cortisol and testosterone levels. Sixteen highly trained volleyball players voluntarily participated in this study. The first testing session (TR state) occurred 1 week before the start of national level volleyball CP, and the second testing session (CP state) occurred next morning after the 1-week CP. Fasted serum sample was used for measuring cortisol and testosterone. Subjects were then orally challenged with 75 g of glucose solution for determinations of oral glucose tolerance test (OGTT) and insulin response. Under both fasted and glucose challenged conditions, glucose levels of CP were not different from TR state, whereas insulin levels of CP were significantly elevated above TR (50 min: from 78.8 +/- 8.7 to 96.6 +/- 8.1 microU/ml, P < 0.05; 80 min: from 62.8 +/- 7.0 to 82.0 +/- 7.3; P < 0.05). Muscle creatine kinase (CK) level in blood was significantly increased above TR, suggesting greater muscle damage by CP. Serum leptin level, percent fat mass, and body weight were not different between two states. CP significantly increased serum cortisol level without significantly change in testosterone level. The new finding of the study was that volleyball CP reduced the whole-body insulin sensitivity significantly compared to TR state. The greater level of insulin concentration under CP state appears to be associated with elevated serum cortisol level. Despites the benefit of increased physical activity on metabolic function is widely recognized, physiological stress associated with CP can result in attenuation of systemic insulin sensitivity compared TR state.

Liquid chromatography-tandem mass spectrometry screening method for the simultaneous detection of stimulants and diuretics in urine.

This study established a simultaneous screening method based on solid-phase extraction and liquid chromatography-tandem mass spectrometry (LC-MS-MS) for the detection of 23 stimulants and 23 diuretics in human urine. An electrospray ionization source and multiple reaction monitoring were used for data acquisition. All stimulants and diuretics were separated in less than 12.52 min. The limits of detection were in the range of 25-500 ng/mL for stimulants and 25-125 ng/mL for diuretics. To evaluate the performance of this method, urine samples were collected from 1627 athletes in Taiwan, and 7 positive samples were found. This LC-MS-MS method not only meets the minimum required performance limits set by the World Anti-Doping Agency but also provides a fast way to analyze the authentic urine samples in doping control laboratories.