Interval training has more negative effects on sleep in adolescent speed skaters: a randomized cross controlled trial.

Objective: Sleep is an essential component of athletic performance and recovery. This study aimed to investigate the effects of different types of high-intensity exercise on sleep parameters in adolescent speed skaters. Methods: Eighteen male adolescent speed skaters underwent aerobic capacity testing, Wingate testing, and interval training in a randomized crossover design to assess strength output, heart rate, and blood lactate levels during exercise. Sleep quality after each type of exercise was evaluated using the Firstbeat Bodyguard 3 monitor. Results: The results showed that Wingate testing and interval training led to decreased sleep duration, increased duration of stress, decreased RMSSD, and increased LF/HF ratio (p < 0.01). Conversely, aerobic capacity testing did not significantly affect sleep (p > 0.05). The impact of interval training on sleep parameters was more significant compared to aerobic capacity testing (p < 0.01) and Wingate testing (p < 0.01). Conclusion: High-intensity anaerobic exercise has a profound impact on athletes' sleep, primarily resulting in decreased sleep duration, increased stress duration, decreased RMSSD, and increased LF/HF ratio.

How to Test the On-Ice Aerobic Capacity of Speed Skaters? An On-Ice Incremental Skating Test for Young Skaters.

Aerobic capacity is important for speed skaters to achieve good results in middle-long distance events. The technical characteristics of speed skating cause intermittent blood flow blockage in the lower limbs. Therefore, an athlete's aerobic capacity on ice may differ from that measured by cycling or running. Now, the on-ice aerobic capacity lacks methods for conducting aerobic capacity tests on ice. Objective: The objective of this study was to develop a method for measuring on-ice aerobic capacity for young athletes and to compare it with the VO2max test on cycling. Methods: This study established a test method for the on-ice aerobic capacity of young, high-level speed skaters with incremental load (on-ice incremental skating test, OIST) through expert interviews and literature review. In the first part, OIST was used to test the aerobic abilities of 65 youth professional speed skaters (51 males and 14 females) on ice and to explore the correlation with their specific performance. The second part compares the relationship between aerobic capacity on ice and aerobic capacity on bicycle of 18 young high-level male athletes. The third part establishes the regression formula of ice ventilation threshold heart rate. The OIST established in this study can evaluate the on-ice aerobic capacity of athletes from National Level and Level 1&2 in China. The athletes' on-ice aerobic capacity indicators were significantly lower than those of the cycling test. However, the values of absolute VO2max and absolute ventilatory threshold had a high correlation (R = 0.532, p < 0.05; R = 0.584, p < 0.05). The regression formula of ventilatory threshold heart rate on ice = 0.921 × HRmax (Cycling test) -9.243. The OIST established in this study meets the characteristics and requirements of the VO2max measurement method. The OIST seems to be able to better evaluate the aerobic capacity of athletes skating on ice. The indicators of maximum oxygen uptake and ventilation threshold in OIST were significantly lower than those in the aerobic cycling test, but there was a good correlation. The aerobic cycling test can be used as an important selection index of the ice aerobic capacity of speed skaters. The regression formula will provide an important basis for coaches to accurately monitor the intensity of ice training.

Effects of high-fat diet and treadmill running on the hypothalamic Kiss-1-GPR54 signaling pathway in male growing rats.

BACKGROUND: Kiss-1 neuron, one of the metabolic sensors in the hypothalamus, is necessary for puberty initiation. It acts through G protein-coupled receptor, known as GPR54. In this study, the mechanism of the hypothalamic Kiss-1-GPR54 signaling pathway in a high-fat diet and exercise was investigated in growing male rats. METHODS: A total of 135 3-week-old male weaned rats were kept on a high-fat diet (HFD) and exercise (60-70% [Formula: see text], 1 h/day, 5 days/week). They were randomly divided, as follows: control group (C); normal diet + exercise group (CE); HFD group (H); and HFD + exercise group (HE). Hypothalamus, testis, and serum samples of each group were collected on postnatal day (PND) 21 (early childhood), 43 (puberty), and 56 (maturity). Immunofluorescence, quantitative real-time PCR, hematoxylin and eosin staining, and chemiluminescent immunoassays were used in the study. ANOVA was used to analyze the effects of age (PNDs 21, 43, and 56), exercise (exercise and sedentariness), and diet (high-fat and normal) on the biological indices of rats. RESULTS: mRNA and protein expression of Kiss-1 and GPR54 in the hypothalamus gradually increased along with growth and peaked at PND 43, while those in serum testosterone increased and peaked at PND 56. The high-fat diet increased the expression of the Kiss-1-GPR54 system in the hypothalamus, whereas the serum testosterone decreased during different stages of growth. Exercise decreased the expression of Kiss-1 at PND 56 and increased it at PND 43. Meanwhile, it decreased testosterone and the deposition of lipid droplets in the testis at all ages of development. CONCLUSIONS: The expression of Kiss-1-GPR54 in male rats showed fluctuating changes during growth and development. The high-fat diet was able to upregulate the expression of the Kiss-1-GPR54 system in the hypothalamus. The exercise was able to correct the adverse effect of the high-fat diet on the Kiss-1-GPR54 signaling pathway in the hypothalamus and the function of the hypothalamic-pituitary-gonadal (HPG) axis, but had age-specific effects on the male rats' development.

BAIBA Involves in Hypoxic Training Induced Browning of White Adipose Tissue in Obese Rats.

In recent years, obesity has become an important risk factor for human health; how to effectively prevent and reduce the occurrence of obesity is a hot research topic in recent years. Hypoxic training effectively improves abnormalities of lipid metabolism caused by obesity. The current study explored the effects of hypoxic training on BAIBA secretion and white fat browning in inguinal fat in obese rats. Analyses were performed by HPLC/MS/MS-MS/MS, RT-q PCR and western blot methods. The findings showed that 4 weeks of hypoxic training reduced body weight, Lee's index, and regulated blood lipid profile in obese rats. Hypoxic training up-regulated BAIBA concentration in gastrocnemius muscle and circulation in obese rats. Hypoxic training significantly upregulated expression of PPARα and UCP-1 in inguinal fat of obese rats and increased white fat browning. The findings showed that BAIBA may involve in improveing blood lipid profile and white fat browning by modulating PPARα and UCP-1 expression.

Long non-coding RNA SPRY4-IT1 as a promising indicator for three field lymph-node dissection of thoracic esophageal carcinoma.

BACKGROUND: Esophageal squamous cell carcinoma(ESCC) is one of the most common tumors worldwide. Esophagectomy with three-field lymph node dissection(3FLND) is the radical surgical procedure for esophageal cancer. However, 3FLND is not widely used due to it's higher mortality rate and higher incidence of postoperative complications. There is an urgent need to identify novel biomarkers that can guide the most proper lymph-node dissection in esophageal cancer patients. METHOD: Ninety-two patients with thoracic ESCC undergoing 3FLND were enrolled into our study from the Department of Thoracic Surgery of the Fourth Hospital affiliated to the Hebei Medical University and Hebei General Hospital between Jun 2011 and Dec 2015. Retrospectively collected data from these 92 patients was used to explore the relationship between the lymph-node metastasis、recurrence and the SPRY4-IT1 expression level and to determine whether 3FLND should be performed in patients with thoracic ESCC. RESULTS: The findings revealed that the SPRY4-IT1 expression was significantly higher in esophageal cancer tissues than in adjacent noncancerous tissues. (P < 0.01). Furthermore, the high expression of SPRY4-IT1 was significantly correlated with tumor differentiation (P = 0.029), T classification (P = 0.013), lymph node metastasis(P = 0.022) and pathological stage (P = 0.001). The increased expression of SPRY4-IT1 was associated with a higher risk of cervical and superior mediastinal lymph-node metastasis(P = 0.039).However, no significant association was observed between the risk of cervical and superior mediastinal lymph-node recurrence and the SPRY4-IT1 expression level in the thoracic ESCC patients performed 3FLND(P = 0.509). CONCLUSIONS: Our data support the assumption that the high expression of SPRY4-IT1 is associated with a high risk of lymph node metastasis and it has potential application as a indicator for guiding on three-field lymph node dissection in patients with thoracic ESCC. Randomized controlled trials with a large cohort of patients will be needed to confirm this conclusion in the future.

The effect of high-fat diet and exercise on KISS-1/GPR54 expression in testis of growing rats.

PURPOSE: To find the expression of KISS-1 and G protein-coupled receptor 54 in rats testis from PND 21st to 56th. METHOD: 128 three-week-old weaned rats underwent high-fat diet and exercise (60-70% VO2max, 1 h/day, 5 days/week) intervention and were randomly divided into group C, CE, HC, or HE. Sample time points were set on the PND 21st, 35th, 43rd, and 56th. The testicular testosterone and the mRNA content, and protein content of KISS-1 and GPR54 in testis tissue were detected by ELISA, RT-qPCR, and Western blotting. RESULT: (1) The protein of KISS-1 and GPR54 increased gradually during the growing period. KISS-1 mRNA peaked at 35D and GPR54 peaked at 43D. (2) High-fat diet affected the expression of the KISS-1/GPR54 system in rat testis and reduced the expression level of KISS-1 protein. (3) 60-70% VO2max exercise decreased the KISS-1/GPR54 expression level. Exercise intervention improved testicular development in rats with a high-fat diet. CONCLUSION: The expression of KISS-1/GPR54 increased during the growing period. High-fat diet can downregulate the protein and gene expression of KISS-1/GPR54 and change the expression trend. 60-70% VO2max exercise decreased the expression of KISS-1/GPR54, which may be involved in the effects of exercise on high-fat dietary sex hormone disorders.

Long non-coding RNA (lncRNA) PGM5P4-AS1 inhibits lung cancer progression by up-regulating leucine zipper tumor suppressor (LZTS3) through sponging microRNA miR-1275.

It is necessary to explore new molecules for the improvement of precise diagnosis and antitumor therapies in lung cancer. LncRNAs (long non-coding RNAs) play an important role in the regulation of cancer cell malignant behavior and tumor development. In this work, we found that a newly discovered lncRNA, lncRNA PGM5P4-AS1, was lower expressed in lung cancer tissues than adjacent tissues. Then, the lncRNA PGM5P4-AS1 was overexpressed or knocked-down in different lung cancer cells, and its effects on the malignant phenotypes were measured by 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, cell cycle assay, wound healing assay, and transwell assay. The results showed that the overexpression of PGM5P4-AS1 inhibited lung cancer cell proliferation, migration, and invasion activities, while these abilities were prominently promoted by the interference of PGM5P4-AS1. Further, the growth of lung cancer tumors in nude mice was also inhibited by PGM5P4-AS1 overexpression. In mechanism, PGM5P4-AS1 has the binding site of miR-1275 and could positively regulate the expression of LZTS3 via sponging miR-1275. In conclusion, PGM5P4-AS1 could be a potential precise diagnosis and therapeutic target biomarker of lung cancer.