To compare the effects of endurance training with endurance strength training on the anthropometric, body composition, physical capacity, and circulatory parameters in obese women.

Preconditioning is often used in medicine to protect organs from ischemic damage and in athletes to enhance the performances. We tested whether low-dose ammonium preconditioning (AMP) could have a beneficial effect on physical exercises (PE). We used Cardiopulmonary Exercise Testing (CPET) on a treadmill to investigate the effects of low-dose AMP on the physical exercise capacity of professional track and field athletes and tested twenty-five athletes. Because of the individual differences between athletes, we performed a preliminary treadmill test (Pre-test) and, according to the results, the athletes were randomly allocated into the AMP and control (placebo, PL) group based on the similarity of the total distance covered on a treadmill. In the AMP group, the covered distance increased (11.3 ± 3.6%, p < 0.02) compared to Pre-test. Similarly, AMP significantly increased O2 uptake volume-VO2 (4.6 ± 2.3%, p < 0.03) and pulmonary CO2 output-VCO2 (8.7 ± 2.8%, p < 0.01). Further, the basic blood parameters (pH, pO2, and lactate) shift was lower despite the greater physical exercise progress in the AMP group compared to Pre-test, whereas in the placebo group there were no differences between Pre-test and Load-test. Importantly, the AMP significantly increased red blood cell count (6.8 ± 2.0%, p < 0.01) and hemoglobin concentration (5.3 ± 1.9%, p < 0.01), which might explain the beneficial effects in physical exercise progress. For the first time, we showed that low-dose AMP had clear beneficial effects on submaximal PE.

Involuntary physical activity induced by the avoidance of electrical shock leads to improved endurance exercise capacity in animals. However, it remains unknown whether voluntary stand-up physical activity (SPA) without forced simulating factors improves endurance exercise capacity in animals. We examined the eff ects of SPA on body weight, cardiac function, and endurance exercise capacity for 12 weeks. Twelve male Sprague-Dawley rats (aged 8 weeks, n=6 per group) were randomly assigned to a control group (CON) or a voluntary SPA group. The rats were induced to perform voluntary SPA (lifting a load equal to their body weight), while the food height (18.0 cm) in cages was increased progressively by 3.5 every 4 weeks until it reached 28.5 cm for 12 weeks. The SPA group showed a lower body weight compared to the CON group, but voluntary SPA did not affect the skeletal muscle and heart weights, food intake, and echocardiography results. Although the SPA group showed higher grip strength, running time, and distance compared to the CON group, the level of irisin, corticosterone, genetic expression of mitochondrial biogenesis, and nuclei numbers were not affected. These findings show that voluntary SPA without any forced stimuli in rats can eff ectively reduce body weight and enhance endurance exercise capacity, suggesting that it may be an important alternative strategy to enhance endurance exercise capacity.

SUR2A is an ATP-binding protein that serves as a regulatory subunit of cardioprotective ATP-sensitive K(+) (K(ATP) ) channels. Based on signalling pathway regulating SUR2A expression and SUR2A role in regulating numbers of fully assembled K(ATP) channels, we have suggested that nicotinamide-rich diet could improve physical endurance by stimulating SUR2A expression. We have found that mice on nicotinamide-rich diet significantly improved physical endurance, which was associated with significant increase in expression of SUR2A. Transgenic mice with solely overexpressed SUR2A on control diet had increased physical endurance in a similar manner as the wild-type mice on nicotinamide-rich diet. The experiments focused on action membrane potential and intracellular Ca(2+) concentration have demonstrated that increased SUR2A expression was associated with the activation of sarcolemmal K(ATP) channels and steady Ca(2+) levels in cardiomyocytes in response to β-adrenergic stimulation. In contrast, the same challenge in the wild-type was characterized by a lack of the channel activation and rise in intracellular Ca(2+) . Nicotinamide-rich diet was ineffective to increase physical endurance in mice lacking K(ATP) channels. This study has shown that nicotinamide-rich diet improves physical endurance by increasing expression of SUR2A and that this is a sole mechanism of the nicotinamide-rich diet effect. The obtained results suggest that oral nicotinamide is a regulator of SUR2A expression and has a potential as a drug that can improve physical endurance in conditions where this effect would be desirable.

Regular running and strength training are the best ways to improve aerobic capacity and develop the size of skeletal muscles. However, uncontrolled physical activities can often lead to an undertraining or over-training syndrome. In particular, overtraining causes persistent fatigue and reduces physical performance due to changes in the various physiological and immunological factors. In this study, we gave an exhaustive submaximal endurance or resistance exercise to participants and investigated the relationship between physical stress (cortisol level in blood), oxidative stress (intracellular ROS accumulation), and adaptive immune response (CD4:CD8 ratio).

Physical inactivity and sedentary behavior are associated with poor well-being in young people with adverse effects extending into adulthood. To date, there are many studies investigating the relationship between physical activity (PA) and posture, but there are no data on the relationship between the type and intensity of PA and sedentary behavior, their association with thoracic and lumbar spine angles, and with endurance and balance of the trunk muscles, especially in healthy young adults aged 18-25 years. Moreover, there are no data on the relationship between PA and sedentary behavior and musculoskeletal and cardiopulmonary health, as well as quality of life (QoL) and sleep that would provide a more comprehensive picture of physical health status.

We previously reported that polymethoxyflavones (PMFs) in black ginger (Kaempferia parviflora) extract (KPE) increased energy production by activating AMP-activated protein kinase (AMPK) in C2C12 myoblasts. We herein evaluated the effects of KPE on physical fitness performance and muscular endurance in mice. Male mice were orally administered KPE for 4 weeks, and then forced swimming test, open-field test, inclined plane test, and wire hanging test were performed. KPE significantly increased the swimming time, motility after swimming, and grip strength. IL-6 and TNF-α mRNA expression levels were decreased in the soleus muscle, whereas peroxisome proliferator-activated receptor γ coactivator (PGC)-1α and glycogen synthase mRNA expression levels, mitochondrial number, and glycogen content were increased. These results were in agreement with those obtained for KPE and PMFs in C2C12. Therefore, the activation of AMPK by PMFs may be one of the mechanisms by which KPE improves physical fitness performance and muscular endurance.

The purpose of this study was to examine potential moderators of school-based physical activity interventions on cardiorespiratory endurance in primary school-aged children using meta-regression. An Internet search with several databases was employed, extracting school-based pediatric physical activity intervention studies published within the past 30 years. Studies were included if there was a control or comparison group, if the study sample included primary school-aged children, if the targeted outcome of cardiorespiratory endurance was objectively assessed, if the intervention was at least partially school-based, and if the effect estimate's variability was reported. An inverse-variance random effects meta-regression was employed using the primary predictors of component number (single component or multi-component) and intervention length using 20 extracted studies with 23 total effects. The overall pooled effect on cardiorespiratory endurance was statistically significant (Hedges' g = 0.30, 95% C.I.: 0.19⁻0.40; p < 0.001). Using random effects meta-regression, neither component number (b = ⁻0.09, 95% C.I.: ⁻0.40⁻0.23; p = 0.560) or intervention length (b = 0.001, 95% C.I.: ⁻0.002⁻0.004; p = 0.427) yielded a significant modifying effect on cardiorespiratory endurance. School-based physical activity interventions have a significant pooled effect on cardiorespiratory endurance in primary school-aged children. Component number and intervention length does not modify this effect, suggesting other sources for between-study heterogeneity.

Brain structure is a fundamental determinant of brain function, both of which decline with age in the adult. Whereas short-term exercise improves brain size in older adults, the impact of endurance training on brain structure when initiated early and sustained throughout life, remains unknown. We tested the hypothesis that long-term competitive aerobic training enhances cortical and subcortical mass compared to middle to older-aged healthy adults who adhere to the minimum physical activity guidelines. Observations were made in 16 masters athletes (MA; 53 ± 6 years, VO2max = 55 ± 10 ml/kg/min, training > 15 years), and 16 active, healthy, and cognitively intact subjects (HA; 58 ± 9 years, VO2max = 38 ± 7 ml/kg/min). T1-weighted structural acquisition at 3T enabled quantification of cortical thickness and subcortical gray and white matter volumes. Cardiorespiratory fitness correlated strongly with whole-brain cortical thickness. Subcortical volumetric mass at the lateral ventricles, R hippocampus, R amygdala, and anterior cingulate cortex, correlated with age but not fitness. In a region-of-interest (ROI) group-based analysis, MA expressed greater cortical thickness in the medial prefrontal cortex, pre and postcentral gyri, and insula. There was no effect of group on the rate of age-related cortical or subcortical decline. The current data suggest that lifelong endurance training that produces high levels of cardiorespiratory fitness, builds cortical reserve early in life, and sustains this benefit over the 40-70 year age span. This reserve likely has important implications for neurological health later in life.

Breast cancer is a persisting global burden for health services with cases and deaths projected to rise in future years. Surgery complemented by adjuvant therapy is commonly used to treat breast cancer, however comes with detrimental side effects to physical fitness and mental wellbeing. The aim of this systematic review and meta-analysis is to determine whether resistance and endurance interventions performed during adjuvant treatment can lastingly ameliorate these side effects. A systematic literature search was performed in various electronic databases. Papers were assessed for bias and grouped based on intervention design. RStudio was used to perform the meta-analyses for each group using the 'meta' package. Publication bias and power analyses were also conducted. These methods conform to PRISMA guidelines. Combined resistance and endurance interventions elicited significant long-lasting improvements in global fatigue and were beneficial to the remaining side effects. Individually, resistance and endurance interventions non-significantly improved these side effects. Resistance interventions elicited higher benefits overall. Exercise interventions have lasting clinical benefits in ameliorating adjuvant therapy side effects, which negatively impact physical fitness and mental wellbeing. These interventions are of clinical value to enhance adherence rates and avoid comorbidities such as sarcopenia, thus improving disease prognosis.

Sarcopenia, a reduction in muscle mass and function seen in aging populations, may be countered by improving systemic carnosine stores via beta-Alanine (β-alanine) supplementation. Increasing systemic carnosine levels may result in enhanced anti-oxidant, neuro-protective and pH buffering capabilities. This enhancement should result in improved exercise capacity and executive function.

The influence of original drugs from Scutellaria baicalensis (SB) Georgi (dry extract, powder of rhizomes and roots, tablets "Scutex" on the basis of the dry extract and capsules "Scutella", which contain powder of rhizomes with roots) was studied on depressive behavior, physical endurance and anti-hypoxic activity in mice.

Every other day feeding (EOD) and exercise induce changes in cell metabolism. The aim of the present work was to know if both EOD and exercise produce similar effects on physical capacity, studying their physiological, biochemical and metabolic effects on muscle. Male OF-1 mice were fed either ad libitum (AL) or under EOD. After 18 weeks under EOD, animals were also trained by using a treadmill for another 6 weeks and then analyzed for physical activity. Both, EOD and endurance exercise increased the resistance of animals to extenuating activity and improved motor coordination. Among the groups that showed the highest performance, AL and EOD trained animals, ALT and EODT respectively, only the EODT group was able to increase glucose and triglycerides levels in plasma after extenuating exercise. No high effects on mitochondrial respiratory chain activities or protein levels neither on coenzyme Q levels were found in gastrocnemius muscle. However, exercise and EOD did increase β-oxidation activity in this muscle accompanied by increased CD36 levels in animals fed under EOD and by changes in shape and localization of mitochondria in muscle fibers. Furthermore, EOD and training decreased muscle damage after strenuous exercise. EOD also reduced the levels of lipid peroxidation in muscle. Our results indicate that EOD improves muscle performance and resistance by increasing lipid catabolism in muscle mitochondria at the same time that prevents lipid peroxidation and muscle damage.

Iron deficiency (ID), with or without anemia, is responsible for physical fatigue. This effect may be linked to an alteration of mitochondrial metabolism. Our aim was to assess the impact of ID on skeletal striated muscle mitochondrial metabolism. Iron-deficient non-anemic mice, obtained using a bloodletting followed by a low-iron diet for three weeks, were compared to control mice. Endurance was assessed using a one-hour submaximal exercise on a Rotarod device and activities of mitochondrial complexes I and IV were measured by spectrophotometry on two types of skeletal striated muscles, the soleus and the quadriceps. As expected, ID mice displayed hematologic markers of ID and reduced iron stores, although none of them were anemic. In ID mice, endurance was significantly reduced and activity of the respiratory chain complex I, normalized to citrate synthase activity, was significantly reduced in the soleus muscle but not in the quadriceps. Complex IV activities were not significantly different, neither in the soleus nor in the quadriceps. We conclude that ID without anemia is responsible for impaired mitochondrial complex I activity in skeletal muscles with predominant oxidative metabolism. These results bring pathophysiological support to explain the improved physical activity observed when correcting ID in human. Further studies are needed to explore the mechanisms underlying this decrease in complex I activity and to assess the role of iron therapy on muscle mitochondrial metabolism.

Background. Approximately 17% of children aged 6-11 years were classified as obese in the United States. Obesity adversely affects physical functioning and leads to reduced quality of life. Heart function for overweight and obese children has not been reported. Methods. Data for this study were from NHANES National Youth Fitness Survey (NNYFS) conducted in conjunction with the National Health and Nutrition Examination Survey (NHANES) in 2012. This study used data from children aged 6-12 (N = 732) that had the cardiorespiratory endurance measure, body mass index for age and sex, and dietary data (N = 682). Cardiovascular endurance was estimated by heart rate reserve. Results. Compared to the highest percentile of heart rate reserve, those in the first percentile had 3.52 (2.36, 5.24) odds and those in the second percentile had 3.61 (1.84, 7.06) odds of being in the overweight/obese as compared to the under/normal weight category. Considering the highest percentile, boys had a heart rate reserve of 35%, whereas girls had a heart rate reserve of 13% (less than half that of boys). Conclusion. Having an overweight or obese classification for children in this study demonstrated a compromise in cardiovascular endurance. Parental awareness should be raised as to the detrimental consequence of overweight and heart health.

To investigate the impact of Tai Chi training on muscle strength, physical endurance, postural balance and flexibility, as measured by tests commonly used in health-related fitness or competitive sports contexts.

This study evaluated the effects of aclidinium bromide, a long-acting muscarinic antagonist indicated for maintenance treatment of chronic obstructive pulmonary disease (COPD), on exercise endurance, dyspnea, lung hyperinflation, and physical activity.

COVID-19 and imposed restrictions are linked with numerous health consequences, especially among endurance athletes (EA). Unfavorable changes in physical activity and nutrition may affect later sports and competition performance. The aims of this study were: (1) to assess the impact of COVID-19 infection and pandemic restrictions on the nutrition and physical activity of EAs and (2) to compare them with the results of cardiopulmonary exercise testing (CPET). In total, 49 EAs (nmale = 43, nfemale = 6, mean age = 39.9 ± 7.8 year., height = 178.4 ± 6.8 cm, weight = 76.3 ± 10.4 kg; BMI = 24.0 ± 2.6 kg·m−2) underwent pre- and post-COVID-19 CPET and fulfilled the dietary and physical activity survey. COVID-19 infection significantly deteriorated CPET performance. There was a reduction in oxygen uptake and in heart rate post-COVID-19 (both p < 0.001). Consuming processed meat and replacing meat with plant-based protein affected blood lactate concentration (p = 0.035). Fat-free mass was linked with consuming unsaturated fatty acids (p = 0.031). Adding salt to meals influenced maximal speed/power (p = 0.024) and breathing frequency (p = 0.033). Dietary and Fitness Practitioners and Medical Professionals should be aware of possible COVID-19 infection and pandemic consequences among EA. The results of this study are a helpful guideline to properly adjust the treatment, nutrition, and training of EA.

Low back pain (LBP) is the leading cause of disability worldwide and often associated with lifestyle factors. However, studies further examining the role of these lifestyle factors in non-specific low back pain in comparison with radicular pain are sparse. The aim of this cross sectional study was to investigate how diverse lifestyle factors are associated with LBP. The study population of 3385 middle aged adults with and without low back pain was drawn from a large Birth 1966 Cohort. Outcome measures were steps per day, abdominal obesity, physical activity and endurance of the back muscles. Back static muscular endurance, abdominal obesity and physical activity were measured by means of the Biering-Sørensen test, waist circumference and a wrist worn accelerometer, respectively. Logistic regression analysis was applied to estimate associations of back static muscular endurance, abdominal obesity and accelerometer-measured physical activity with non-specific low back pain and radicular pain. An additional 1000 steps per day were associated with 4% lower odds of having non-specific low back pain. Participants with abdominal obesity had 46% higher odds of having radicular pain, whereas increases of 10 s in back static muscular endurance and 10 min in daily vigorous physical activity were associated with 5% and 7% lower odds of having radicular pain, respectively. In this population-based study, non-specific low back pain and radicular pain were associated with different lifestyle and physical factors at midlife. Non-specific low back pain was associated only with the average daily number of steps, whereas abdominal obesity was the strongest determinant of radicular pain, followed by vigorous physical activity and back static muscular endurance. The findings of this study contribute to better understand the role of lifestyle factors in both non-specific low back pain and radicular pain. Future longitudinal studies are required to explore causality.

Combining training of muscle strength and cardiorespiratory fitness within a training cycle could increase athletic performance more than single-mode training. However, the physiological effects produced by each training modality could also interfere with each other, improving athletic performance less than single-mode training. Because anthropometric, physiological, and biomechanical differences between young and adult athletes can affect the responses to exercise training, young athletes might respond differently to concurrent training (CT) compared with adults. Thus, the aim of the present systematic review with meta-analysis was to determine the effects of concurrent strength and endurance training on selected physical fitness components and athletic performance in youth. A systematic literature search of PubMed and Web of Science identified 886 records. The studies included in the analyses examined children (girls age 6-11 years, boys age 6-13 years) or adolescents (girls age 12-18 years, boys age 14-18 years), compared CT with single-mode endurance (ET) or strength training (ST), and reported at least one strength/power-(e.g., jump height), endurance-(e.g., peak V°O2, exercise economy), or performance-related (e.g., time trial) outcome. We calculated weighted standardized mean differences (SMDs). CT compared to ET produced small effects in favor of CT on athletic performance (n = 11 studies, SMD = 0.41, p = 0.04) and trivial effects on cardiorespiratory endurance (n = 4 studies, SMD = 0.04, p = 0.86) and exercise economy (n = 5 studies, SMD = 0.16, p = 0.49) in young athletes. A sub-analysis of chronological age revealed a trend toward larger effects of CT vs. ET on athletic performance in adolescents (SMD = 0.52) compared with children (SMD = 0.17). CT compared with ST had small effects in favor of CT on muscle power (n = 4 studies, SMD = 0.23, p = 0.04). In conclusion, CT is more effective than single-mode ET or ST in improving selected measures of physical fitness and athletic performance in youth. Specifically, CT compared with ET improved athletic performance in children and particularly adolescents. Finally, CT was more effective than ST in improving muscle power in youth.