Association of left ventricular global area strain derived from resting 3D speckle-tracking echocardiography and exercise capacity in individuals undergoing treadmill exercise test

Background: Left ventricular (LV) global area strain (GAS) is a novel index derived from resting 3D speckle-tracking echocardiography (STE), and its clinical significance has rarely been studied. We examined the association of LV GAS and exercise capacity in a health check-up population.Methods: We recruited 94 symptom-free participants (52.2 ± 11.7 years, 62.8% male) without substantial structural heart disease or coronary heart diseases who were undergoing a routine health examination. All participants underwent resting echocardiography and symptom-limited treadmill exercise test according to the Bruce protocol. Four strain parameters were obtained from the analysis, namely 3D GAS (GAS3d), global longitudinal strain, global circumferential strain, and global radial strain.Results: After multivariate analysis for factors of exercise time, we observed a significant association in LV GAS3d (P < 0.001). We divided participants into preserved and impaired exercise capacity groups according to the cutoff value of 8 metabolic equivalent of tasks. LV GAS3d (OR 1.24, 95% CI 1.10-1.39, P < 0.001) was an independent predictor of impaired exercise capacity and the optimal cut-off value was -19.96% at a sensitivity of 77.8% and at a specificity of 92.1%. LV GAS3d could improve the discriminatory power of exercise capacity in individuals with early mitral filling velocity to average mitral annulus velocity ratio (E/e'') ≥ 8.Conclusions: LV GAS3d was significantly associated with exercise time and exhibited incremental predictive value on E/e'' for exercise capacity in participants undergoing treadmill exercise test.     

Effects of schedule exercise therapy on chronic insomnia

Schedule exercise therapy (SET) is a novel nonpharmacological intervention for the treatment of chronic insomnia disorder (CID). The aim of this study was to explore the effects of SET on CID. Methods: One hundred and eighteen CID were recruited and randomized into medication (MED) or medication combined with SET (MSET) groups. Over 12 observational weeks, sleep and mood status were evaluated using the Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), Epworth Sleepiness Scale (ESS), Self-rating Depression Scale (SDS), and Self-rating Anxiety Scale (SAS). At the end of the observational period, the rates of clinically effective hypnotic use were calculated. At 12 weeks, the PSQI progressively decreased for all subjects combined (P < .001) as well as ISI (P < .001), ESS (P < .001), SDS (P < .001), and SAS (P < .001). The decreases in PSQI (P < .05), ISI (P < .05), SDS (P < .01), and SAS (P < .05) in the MSET group were significantly larger than those in the MED group, but not the same as those in the ESS group (P > .05). At the trial endpoint, the clinically effective rate was significantly higher (P < .05) and the hypnotic usage rate was lower (P < .05) in the MSET group than in the MED group. SET may be an effective treatment for insomnia in patients with CID.     

Effects of Citrulline Supplementation on Different Aerobic Exercise Performance Outcomes: A Systematic Review and Meta-Analysis

Supplementation with Citrulline (Cit) has been shown to have a positive impact on aerobic exercise performance and related outcomes such as lactate, oxygen uptake (VO₂) kinetics, and the rate of perceived exertion (RPE), probably due to its relationship to endogenous nitric oxide production. However, current research has shown this to be controversial. The main objective of this systematic review and meta-analysis was to analyze and assess the effects of Cit supplementation on aerobic exercise performance and related outcomes, as well as to show the most suitable doses and timing of ingestion. A structured literature search was carried out by the PRISMA^® (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) and PICOS guidelines in the following databases: Pubmed/Medline, Scopus, and Web of Science (WOS). A total of 10 studies were included in the analysis, all of which exclusively compared the effects of Cit supplementation with those of a placebo group on aerobic performance, lactate, VO₂, and the RPE. Those articles that used other supplements and measured other outcomes were excluded. The meta-analysis was carried out using Hedges’ g random effects model and pooled standardized mean differences (SMD). The results showed no positive effects of Cit supplementation on aerobic performance (pooled SMD = 0.15; 95% CI (−0.02 to 0.32); I², 0%; p = 0.08), the RPE (pooled SMD = −0.03; 95% CI (−0.43 to 0.38); I², 49%; p = 0.9), VO₂ kinetics (pooled SMD = 0.01; 95% CI (−0.16 to 0.17); I², 0%; p = 0.94), and lactate (pooled SMD = 0.25; 95% CI (−0.10 to 0.59); I², 0%; p = 0.16). In conclusion, Cit supplementation did not prove to have any benefits for aerobic exercise performance and related outcomes. Where chronic protocols seemed to show a positive tendency, more studies in the field are needed to better understand the effects.     

Does Regular Physical Activity Improve Personal Income? Empirical Evidence from China

A lack of adequate exercise threatens human health, weakening human capital accumulation. The relationship between exercise and income has become the focus of attention in health economics. In terms of reducing body weight and improving physical fitness, diet and physical exercise are intertwined and become effective ways to shape a healthy state. Based on individual-level survey data from China, this study quantified the economic returns of habitual exercise behavior by using an endogenous switching regression model (ESRM) to eliminate selection bias. The study shows that (1) participants in the group with regular exercise behavior increased their income by 3.79% compared with those not exercising regularly; (2) for the group with no regular exercise behavior, regular exercise increased their income by 13.36% compared with those not exercising regularly. Additionally, empirical evidence shows that both drinking and smoking can significantly increase individual income, despite unhealthy habits. These results suggest that the habit of regular physical activity plays a vital role in increasing individual income and improving overall national health, and the effect of individual behavior on income is affected by national culture. The outcomes are empirical evidence for the Chinese government to promote Healthy China Action and support developing countries worldwide to enable habitual exercise, stimulating a policy of exercise behavior.     

Aerobic Exercise Prevents Chronic Inflammation and Insulin Resistance in Skeletal Muscle of High-Fat Diet Mice

Obesity is commonly accompanied by chronic tissue inflammation and leads to insulin resistance. Aerobic exercise is an essential treatment for insulin resistance and has anti-inflammatory effects. However, the molecular mechanisms of exercise on obesity-associated inflammation and insulin resistance remain largely unknown. Here, we evaluated the effects of aerobic exercise on inflammation and insulin resistance in skeletal muscles of high-fat diet (HFD) mice. Male C57BL/6J mice were fed a high-fat diet or a normal diet for 12 weeks, and then aerobic training was performed on a treadmill for 8 weeks. Body weight, fasting blood glucose, food intake levels, and glucose and insulin tolerance were evaluated. The levels of cytokines, skeletal muscle insulin resistance, and inflammation were also analyzed. Eight weeks of aerobic exercise attenuated HFD-induced weight gain and glucose intolerance, and improved insulin sensitivity. This was accompanied by enhanced insulin signaling. Exercise directly resulted in a significant reduction of lipid content, inflammation, and macrophage infiltration in skeletal muscles. Moreover, exercise alleviated HFD-mediated inflammation by suppressing the activation of the NF-κB pathway within skeletal muscles. These results revealed that aerobic exercise could lead to an anti-inflammatory phenotype with protection from skeletal muscle insulin resistance in HFD-induced mice.     

Nutritional Compounds to Improve Post-Exercise Recovery

The metabolic and mechanical stresses associated with muscle-fatiguing exercise result in perturbations to bodily tissues that lead to exercise-induced muscle damage (EIMD), a state of fatigue involving oxidative stress and inflammation that is accompanied by muscle weakness, pain and a reduced ability to perform subsequent training sessions or competitions. This review collates evidence from previous research on a wide range of nutritional compounds that have the potential to speed up post-exercise recovery. We show that of the numerous compounds investigated thus far, only two—tart cherry and omega-3 fatty acids—are supported by substantial research evidence. Further studies are required to clarify the potential effects of other compounds presented here, many of which have been used since ancient times to treat conditions associated with inflammation and disease.     

Glucose and Fructose Supplementation and Their Acute Effects on Anaerobic Endurance and Resistance Exercise Performance in Healthy Individuals: A Double-Blind Randomized Placebo-Controlled Crossover Trial

Background: The effects of glucose, fructose and a combination of these on physical performance have been subject of investigation, resulting in diverse findings. Objective: The aim of this study was to investigate how an individualized amount of glucose, fructose, and a combination of these compared to placebo (sucralose) alter endurance performance on a cycle ergometer, lower and upper body resistance exercise performance at individualized thresholds in healthy young individuals. Methods: A total of 16 healthy adults (9 females) with an age of 23.8 ± 1.6 years and a BMI of 22.6 ± 1.8 kg/m² (body mass (BM) 70.9 ± 10.8 kg, height 1.76 ± 0.08 m) participated in this study. During the screening visit, the lactate turn point 2 (LTP2) was defined and the weights for chest-press and leg-press were determined. Furthermore, 30 min prior to each exercise session, participants received either 1 g/kg BM of glucose (Glu), 1 g/kg BM of fructose (Fru), 0.5 g/kg BM of glucose/fructose (GluFru) (each), or 0.2 g sucralose (placebo), respectively, which were dissolved in 300 mL of water. All exercises were performed until volitional exhaustion. Time until exhaustion (TTE) and cardio-pulmonary variables were determined for all cycling visits; during resistance exercise, repetitions until muscular failure were counted and time was measured. During all visits, capillary blood glucose and blood lactate concentrations as well as venous insulin levels were measured. Results: TTE in cycling was 449 ± 163 s (s) (Glu), 443 ± 156 s (Fru), 429 ± 160 s (GluFru) and 466 ± 162 s (Pla) (p = 0.48). TTE during chest-press sessions was 180 ± 95 s (Glu), 180 ± 92 s (Fru), 172 ± 78 s (GluFru) and 162 ± 66 s (Pla) (p = 0.25), respectively. Conclusions: Pre-exercise supplementation of Glu, Fru and a combination of these did not have an ergogenic effect on high-intensity anaerobic endurance performance and on upper and lower body moderate resistance exercise in comparison to placebo.