Critical power is a key threshold determining the magnitude of post-exercise hypotension in non-hypertensive young males.

The effect of different exercise intensities on the magnitude of post-exercise hypotension has not been rigorously clarified with respect to the metabolic thresholds that partition discrete exercise intensity domains (i.e., critical power and the gas exchange threshold (GET)). We hypothesized that the magnitude of post-exercise hypotension would be greater following isocaloric exercise performed above versus below critical power. Twelve non-hypertensive men completed a ramp incremental exercise test to determine maximal oxygen uptake and the GET, followed by five exhaustive constant load trials to determine critical power and W' (work available above critical power). Subsequently, criterion trials were performed at four discrete intensities matched for total work performed (i.e., isocaloric) to determine the impact of exercise intensity on post-exercise hypotension: 10% above critical power (10% > CP), 10% below critical power (10% < CP), 10% above GET (10% > GET) and 10% below GET (10% < GET). The post-exercise decrease (i.e., the minimum post-exercise values) in mean arterial (10% > CP: -12.7 ± 8.3 vs. 10% < CP: v3.5 ± 2.9 mmHg), diastolic (10% > CP: -9.6 ± 9.8 vs. 10% < CP: -1.4 ± 5.0 mmHg) and systolic (10% > CP: -23.8 ± 7.0 vs. 10% < CP: -9.9 ± 4.3 mmHg) blood pressures were greater following exercise performed 10% > CP compared to all other trials (all P < 0.01). No effects of exercise intensity on the magnitude of post-exercise hypotension were observed during exercise performed below critical power (all P > 0.05). Critical power represents a threshold above which the magnitude of post-exercise hypotension is greatly augmented. NEW FINDINGS: What is the central questions of this study? What is the influence of exercise intensity on the magnitude of post-exercise hypotension with respect to metabolic thresholds? What is the main finding and its importance? The magnitude of post-exercise hypotension is greatly increased following exercise performed above critical power. However, below critical power, there was no clear effect of exercise intensity on the magnitude of post-exercise hypotension.

Recent advances in enzyme-related biomaterials for arthritis treatment.

Arthritis is a group of highly prevalent joint disorders, and osteoarthritis (OA) and rheumatoid arthritis are the two most common types. The high prevalence of arthritis causes severe burdens on individuals, society and the economy. Currently, the primary treatment of arthritis is to relieve symptoms, but the development of arthritis cannot be effectively prevented. Studies have revealed that the disrupted balance of enzymes determines the pathological changes in arthritis. In particular, the increased levels of matrix metalloproteinases and the decreased expression of endogenous antioxidant enzymes promote the progression of arthritis. New therapeutic strategies have been developed based on the expression characteristics of these enzymes. Biomaterials have been designed that are responsive when the destructive enzymes MMPs are increased or have the activities of the antioxidant enzymes that play a protective role in arthritis. Here, we summarize recent studies on biomaterials associated with MMPs and antioxidant enzymes involved in the pathological process of arthritis. These enzyme-related biomaterials have been shown to be beneficial for arthritis treatment, but there are still some problems that need to be solved to improve efficacy, especially penetrating the deeper layer of articular cartilage and targeting osteoclasts in subchondral bone. In conclusion, enzyme-related nano-therapy is challenging and promising for arthritis treatment.

Effectiveness of Yijinjing on cognitive functions in post-stroke patients with mild cognitive impairment: study protocol for a randomized controlled trial.

BACKGROUND: Statistics show that every year, 5.4 million people in the world suffer a stroke. Post-stroke cognitive impairment (PSCI) is one of the most common complications after stroke with a rate of 75%, which leads to decreased functions for independent living and reduced quality of life (QOL). Exercise training has been reported to be useful to improve the cognitive functions of post-stroke patients. Yijinjing, a traditional Chinese Qigong exercise characterized by an integration of mind and body in moderate exercise intensity, can improve cognitive functions of PSCI patients. This study aims to explore the feasibility and effectiveness of the Yijinjing exercise in this regard. METHODS: A single-blind, superiority, randomized controlled trial will be employed with evaluations at 3 and 6 months. Seventy-two PSCI patients will be recruited and randomly assigned to the Yijinjing exercise intervention group or the control group (1:1). Participants in the control group will receive routine rehabilitation therapies, including occupational therapy, physical therapy, acupuncture therapy, and health education 5 times a week for 3 months. The intervention group will receive a 12-week routine rehabilitation therapy combined with the Yijinjing exercise intervention for 40 min each session and 3 sessions a week. The primary outcome of cognition will be measured by the Montreal Cognitive Assessment scale (MoCA). Secondary outcomes include executive function, memory function, visuospatial function, sleep quality, gait and motor function, activity of daily living (ADL), and quality of life (QOL). DISCUSSION: Current evidence has reported the effectiveness of traditional Chinese exercise in improving the post-stroke population's motor functions. This research is a randomized controlled trial that evaluates traditional Chinese exercise's effectiveness for PSCI patients. It is expected to expand the traditional Chinese exercise scope and provide a new treatment approach for stroke populations with cognitive impairments. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR1900026532 . Registered on 13 October 2019.

Does the Conversion of Household Registration Actually Improve the Happiness of Migrant Workers in China?

Migrant workers are an important human resource for economic and social development. Considering the government's goal of serving and improving people's livelihoods, improving the happiness of migrant workers is necessary. This study investigates in-depth the impact of the conversion of household registration on migrant workers' happiness, which is represented by a multi-dimensional comprehensive index based on the propensity matching score model and data from the China Migrants Dynamic Survey (CMDS) in 2017. Moreover, this study explores the different effects of conversion among the groups divided by the characteristics of migrant workers. The results show that from an overall perspective, although the conversion of household registration could improve the happiness of migrant workers, the degree of this improvement is minor. Further, the characteristics of the different groups, including age, educational background, contracted land, collective dividends, and income significantly affect the improvement of happiness. The conversion of household registration has obviously improved the happiness of migrant workers with low educational backgrounds, low income, and contracted land. Based on these findings, the government should take more targeted actions to improve the positive effects of household registration among different migrant worker groups due to the different characteristics in the process of household registration system reform.