The effects of endurance exercise combined with high-temperature head-out water immersion on serum concentration of brain-derived neurotrophic factor in healthy young men.

OBJECTIVES: To evaluate acute changes in serum brain-derived neurotrophic factor (BDNF) concentration following combined endurance exercise and heat stress through head-out water immersion (HOI). SETTING: Observational study with crossover design. METHODS: Ten healthy young male participants performed HOI at 40 °C (40 °C HOI) or continuous cycling at 60% of maximal oxygen uptake while immersed in 40 °C (40 °C HOI-ex) or 23 °C water (23 °C HOI-ex) for 15 min. Serum BDNF, cortisol and lactate concentrations, and core temperature (Tcore) were measured pre, immediately post, and 15 and 30 min post-immersion. RESULTS: BDNF concentration increased immediately and 15 min after 40 °C HOI-ex, but not after 40 °C or 23 °C HOI-ex. No changes in Tcore concentration were observed during 23 °C HOI-ex (Pre; 37.3 °C ± 0.3 °C, Post; 37.8 °C ± 0.2 °C, Post 15; 37.4 °C ± 0.3 °C, Post 30; 37.2 °C ± 0.2 °C). Tcore increased significantly post, post 15, and post 30 min of 40 °C HOI (Pre; 37.1 °C ± 0.4 °C, Post; 38.8 °C ± 0.5 °C, Post 15; 37.9 °C ± 0.4 °C, Post 30; 37.9 °C ± 0.2 °C) and 40 °C HOI-ex (Pre; 37.2 °C ± 0.2 °C, Post; 40.2 °C ± 0.7 °C, Post 15; 38.9 °C ± 0.5 °C, Post 30; 38.3 °C ± 0.5 °C). Tcore was higher in 40 °C HOI-ex compared with 40 °C HOI and 23 °C HOI-ex immediately post and post 15 min. Plasma lactate and cortisol were significantly higher in 40 °C HOI-ex compared with 40 °C HOI and 23 °C HOI-ex after immersion (p = 0.001). CONCLUSION: While 15 min HOI alone or thermoneutral exercise do not increase BDNF concentration, both combined may form a time-efficient strategy to acutely elevate BDNF.

Effects of a Single Session of Acupuncture Treatment on Blood Pressure and Heart Rate Variability in Patients with Mild Hypertension.

Objective: The aim of the present study was to compare the effects of acupuncture treatment on arterial blood pressure (BP) and heart rate (HR) in patients with mild hypertension with high sympathetic tone with those of normotensive patients and to examine the effects on cardiac sympathetic nerve activity (CSNA) and vagal activity using heart rate variability (HRV) analysis. Design: Eight male patients with prehypertension or stage I hypertension and eight normotensive age-matched patients were included in this study. All patients had their systolic BP (SBP), diastolic BP (DBP), HR, and HRV measured. In addition, the ratio of low-frequency (LF) to high-frequency (HF) HRV and the power of the HF of the HRV were recorded. The study was conducted at Kansai University of Health Sciences in Japan. Interventions: Each patient underwent a single, 15-min-long acupuncture session. Acupuncture was applied to PC6, LI4, ST36, LR3 on both sides, and GV20. Results: SBP and HR decreased significantly in the hypertensive group during and after acupuncture compared with the baseline SBP and HR (p < 0.05). LF/HF was significantly reduced during acupuncture (p < 0.05), and HF was significantly increased after acupuncture in the hypertensive group (p < 0.05). However, there were no significant changes in LF/HF or HF in the control group. Conclusions: Acupuncture may reduce the BP and HR in patients with mild hypertension. An HRV analysis suggests that acupuncture may suppress the enhanced basal CSNA activity and increase the vagal nerve activity in patients with mild hypertension. Clinical Trial Registration number: UMIN000041249.

The effects of local versus systemic passive heating on the acute inflammatory, vascular and glycaemic response.

The aim of this study was to compare the acute cardiometabolic and perceptual responses between local and whole-body passive heating. Using a water-perfused suit, 10 recreationally active males underwent three 90 min conditions: heating of the legs with upper-body cooling (LBH), whole-body heating (WBH) and exposure to a thermoneutral temperature (CON). Blood samples were collected before and up to 3 h post-session to assess inflammatory markers, while a 2 h oral glucose tolerance test was initiated 1 h post-session. Femoral artery blood flow and perceptual responses were recorded at regular intervals. The interleukin (IL)-6 incremental area under the curve (iAUC) was higher for LBH (1096 ± 851 pg/mL × 270 min) and WBH (833 ± 476 pg/mL × 270 min) compared with CON (565 ± 325 pg/mL × 270 min; p < 0.047). Glucose concentrations were higher after WBH compared with LBH and CON (p < 0.046). Femoral artery blood flow was higher at the end of WBH (1713 ± 409 mL/min) compared with LBH (943 ± 349 mL/min; p < 0.001), and higher in LBH than CON (661 ± 222 mL/min; p = 0.002). Affect and thermal comfort were more negative during WBH compared with LBH and CON (p < 0.010). In conclusion, local passive heating elevated blood flow and the IL-6 iAUC. However, while resulting in more positive perceptual responses, the majority of the included cardiometabolic markers were attenuated compared with WBH. Novelty: The increase in the IL-6 iAUC in response to passive heating is not reduced by upper-body cooling. Upper-body cooling attenuates the plasma nitrite, IL-1ra and femoral artery blood flow response to passive heating. Upper-body cooling leads to more positive perceptual responses to passive heating.

Activation of mesolimbic reward system via laterodorsal tegmental nucleus and hypothalamus in exercise-induced hypoalgesia.

Ventral tegmental area (VTA) dopamine (DA) neurons are the primary source of dopamine in target structures that constitute the mesolimbic reward system. Previous studies demonstrated that voluntary wheel running (VWR) by neuropathic pain (NPP) model mice produces exercise-induced hypoalgesia (EIH), and that activation of mesolimbic reward system may lead to EIH. However, the neuronal mechanism by which the mesolimbic reward system is activated by VWR is unknown. Here, we found that VWR produces EIH effects and reverses the marked reduction in activated lateral VTA (lVTA)-DA neurons induced by NPP. The proportions of activated laterodorsal tegmental nucleus (LDT)-cholinergic and lateral hypothalamus-orexin neurons were significantly enhanced by VWR. Retrograde tracing and dual immunostaining revealed that VWR activates lVTA-projecting LDT-cholinergic/non-cholinergic and lateral hypothalamic area (LHA)-orexin/non-orexin neurons. Therefore, EIH effects may be produced, at least in part, by activation of the mesolimbic reward system via activation of LDT and LHA neurons.

Effects of acupuncture at the ST-36 point on muscle sympathetic nerve activity and blood pressure in normal adults.

The aim of the present study was to determine the effects of acupuncture on post-ganglionic muscle sympathetic nerve activity (MSNA) in humans. MSNA was measured in 8 healthy adult males by microneurography evaluation of the left peroneal nerve. Blood pressure (BP) and heart rate (HR) were simultaneously recorded. MSNA was evaluated as the burst rate, with total MSNA, BP and HR normalized to their respective baseline values. After 10min of rest in the supine position, acupuncture was applied to the right ST-36 point in the tibialis anterior muscle for 15min, with recovery then monitored over a 20-min period. While the burst rate and total MSNA remained constant throughout the study, there was a significant decrease in BP during the real but not sham acupuncture procedure (p<0.05). HR did not significantly change throughout the study. The results rule out the role of MSNA in the BP fall during acupuncture at the ST-36 point, and suggest possible involvement of other factors in the fall of BP.

Positive effects of a qigong and aerobic exercise program on physical health in elderly Japanese women: an exploratory study.

OBJECTIVE: To determine the effects of a 12-week qigong and aerobic exercise program on the physical well-being of relatively healthy elderly Japanese women. METHODS: In the first study, 72 elderly Japanese women who were relatively healthy and naive to qigong completed the 12-week qigong and aerobic exercise program. Physical function, body composition, and abdominal fat were evaluated. In the second study, we examined the effects of qigong alone on physical function. Twenty-nine participants in each of two groups (divided according to their residences) underwent a 12-week program: qigong and aerobic exercise (residents in Yura Town) or qigong exercise alone (residents in Mihama Town). RESULTS: In the first study, physical function including lung capacity, trunk bending, normal walking for 30 m, and rising from a supine position significantly improved after the 12-week program. In addition, body fat diminished significantly during the program. In the second study, both exercise programs ("qigong and aerobic" and "qigong alone") similarly increased walking speed (normal and maximum walking) and rising speed. CONCLUSIONS: The findings of this exploratory study demonstrated that a 12-week qigong and aerobic exercise program was associated with improvements in physical function and a reduction in body fat. The qigong exercise program alone positively influenced physical function. The qigong program appears to be an appealing means of improving the physical health of elderly persons.