Activation changes in the prefrontal cortex (PFC) regions have been linked to acute exercise-induced improvements in cognitive performance. The type of exercise performed may influence PFC activation, and further impact cognitive function. The present study aimed to compare PFC activation during cognitive testing after moderate-intensity, high intensity, and yoga exercises, and to determine if PFC activation is linked to cognitive performance. Eight subjects (four male and four female), aged 35 ± 5 completed a control, high intensity, moderate intensity, and yoga exercises followed by administration of a cognitive task (NIH Toolbox Fluid Cognition). Left and right PFC activation (LPFC and RPFC, respectively) were evaluated by measuring hemoglobin difference (Hbdiff) changes during post-exercise cognitive assessment using functional near infrared spectroscopy (fNIRS). Activation during the cognitive test was higher in the LPFC after moderate intensity exercise compared to control, high intensity, and yoga (5.30 ± 6.65 vs. 2.26 ± 2.40, 2.50 ± 1.48, 2.41 ± 2.36 μM, p < 0.05, respectively). A negative relationship was detected between LPFC and processing speed after exercise. PFC activation did not align with cognitive performance. However, acute exercise, regardless of type, appeared to alter neural processing. Specifically, less PFC activation was required for a given neural output after exercise.

Hypoxia induced intestinal barrier injury, microbial translocation, and local/systemic inflammation may contribute to high‐altitude associated gastrointestinal complications or symptoms of acute mountain sickness (AMS). Therefore, we tested the hypothesis that six‐hours of hypobaric hypoxia increases circulating markers of intestinal barrier injury and inflammation. A secondary aim was to determine if the changes in these markers were different between those with and without AMS. Thirteen participants were exposed to six hours of hypobaric hypoxia, simulating an altitude of 4572 m. Participants completed two 30‐minute bouts of exercise during the early hours of hypoxic exposure to mimic typical activity required by those at high altitude. Pre‐ and post‐exposure blood samples were assessed for circulating markers of intestinal barrier injury and inflammation. Data below are presented as mean ± standard deviation or median [interquartile range]. Intestinal fatty acid binding protein (Δ251 [103–410] pg•mL⁻¹; p = 0.002, d = 0.32), lipopolysaccharide binding protein (Δ2 ± 2.4 μg•mL⁻¹; p = 0.011; d = 0.48), tumor necrosis factor‐α (Δ10.2 [3–42.2] pg•mL⁻¹; p = 0.005; d = 0.25), interleukin‐1β (Δ1.5 [0–6.7] pg•mL⁻¹ p = 0.042; d = 0.18), and interleukin‐1 receptor agonist (Δ3.4 [0.4–5.2] pg•mL⁻¹p = 0.002; d = 0.23) increased from pre‐ to post‐hypoxia. Six of the 13 participants developed AMS; however, the pre‐ to post‐hypoxia changes for each marker were not different between those with and without AMS (p > 0.05 for all indices). These data provide evidence that high altitude exposures can lead to intestinal barrier injury, which may be an important consideration for mountaineers, military personnel, wildland firefighters, and athletes who travel to high altitudes to perform physical work or exercise.

Background: Previous studies of the Elevation Training Mask (ETM) describe comparisons between groups using the ETM and controls for effects on aerobic performance. However, comparisons have not been made to intermittent hypoxic training (IHT). Further, how the ETM impacts exercise economy is unknown. Therefore, we sought to determine the effects of training with the ETM compared to IHT on aerobic performance and cycling economy. Methods: Thirty participants were randomized into an ETM, IHT, or control group (n = 10 each). Pre-and post-testing occurred using a ramp VO2max test on a cycle ergometer allowing submaximal power output (PO) measures of economy. Economy was measured using POs of 100, 125, and 150W. High-intensity cycling interval training (HIIT) occurred 2x/week for 30 min/session for six weeks. Sessions were 20 min of HIIT (30s at 100% peak power output (PPO) of pre VO2max, 90s active recovery at 25W, 10 bouts) with a 5-minute warm-up and cool-down. Repeated measures ANOVA was used for statistical analyses. RESULTS: All participants improved VO2max, PPO, and PO at ventilatory threshold 2 pre-to post-training (p < 0.05). Interactions between groups showed that the RER for the IHT group

Bellovary, Bryanne N., Andrew D. Wells, Zachary J. Fennel, Jeremy B. Ducharme, Jonathan M. Houck, Trevor J. Mayschak, Ann L. Gibson, Scott N. Drum, and Christine M. Mermier. Could orthostatic stress responses predict acute mountain sickness susceptibility before high altitude travel? A pilot study. High Alt Med Biol . 24:19–26, 2023. Purpose: This study assessed head-up tilt (HUT) responses in relation to acute mountain sickness (AMS)-susceptibility during hypoxic exposure. Materials and Methods: Fifteen participants completed three lab visits: (1) protocol familiarization and cycle maximal oxygen consumption (VO ₂ max) test; (2) HUT test consisting of supine rest for 20 minutes followed by 70° tilting for ≤40 minutes; and (3) 6 hours of hypobaric hypoxic exposure (4,572 m) where participants performed two 30-minute cycling bouts separated by 1 hour at a 50% VO ₂ max workload within the first 3 hours and rested when not exercising. During HUT, systolic blood pressure (SBP), diastolic blood pressure, heart rate (HR), and variability (blood pressure variability [BPV] and HR variability [HRV]) were measured continuously. The AMS scores were determined after 6 hours of exposure. Correlations determined relationships between HUT cardiovascular responses and AMS scores. Repeated-measures analysis of variance (ANOVA) assessed differences between those with and without AMS symptoms during HUT. Results: Higher AMS scores correlated with greater change in SBP variability ( r = 0.52, p = 0.048) and blunted changes in HRV (root mean square of successive differences between normal heartbeats r = 0.81, p = 0.001, percentage of adjacent normal sinus intervals that differ by more than 50 milliseconds [pNN50] r = 0.87, p < 0.001) during HUT. A pNN50 interaction ( p = 0.02) suggested elevated cardiac sympathetic activity at baseline and a blunted increase in cardiac sympathetic influence throughout HUT in those with AMS (pNN50 baseline: AMS = 26.2% ± 15.3%, no AMS = 51.0% ± 13.5%; first 3 minutes into HUT: AMS = 17.2% ± 19.1%, no AMS = 17.1% ± 10.9%; end of HUT: AMS = 6.2% ± 9.1%, no AMS 11.0% ± 10.0%). Conclusions: The results suggest autonomic responses via HUT differ in AMS-susceptible individuals. Changes in HRV and BPV during HUT may be a promising predictive measurement for AMS-susceptibility, but further research is needed for confirmation.

: Osteoporosis is one of the most important problems associated with aging. Genetic and environmental agents affect the process of reducing bone mineral density (BMD). As environmental agents, mechanical load (something which exerts an opposing force on the system; hence system needs more power to perform that work) is the important factor, which affects BMD. Studies show that a variety of exercise programs, depending on the amount of mechanical load they apply to the bone, activate the signaling pathways involved in the process of osteoblast activation and reduce osteoclast activity. The effect of physical activity (PA) on BMD is a function of the intensity, duration, and type of program used. Although the existing literature shows that regular PA increases BMD and subsequently develops its strength, there are conflicting results regarding the effectiveness of exercise programs that confirm the need for further study in this area.

Background: Hormone therapy is a highly effective method for treating menopausal disorders. However, its side effects may include an increased risk of cancer, heart disease, and pulmonary embolism. Previous research has demonstrated that both exercise and nutrition separately have positive effects on menopausal symptoms. Therefore, we suggest that combining exercise and nutrition interventions may provide a synergistic effect, yielding results at least similar to those of estrogen (Est) therapy. Objectives: This study aims to compare the independent and combined effects of resistance training (RT), Est therapy, and vitamin D calcium chitosan (Vit D + Ca++ + Chit) supplementation on markers of bone turnover in ovariectomized (OVX) rats. Methods: Forty-two female Wistar rats were randomly divided into seven groups (n = 6 per group): (1) healthy-control (He-Co), (2) OVX-Vit D + Ca++ + Chit + RT, (3) OVX-saline (Sal) + Est + RT, (4) Sal + RT, (5) OVX-Vit D + Ca++ +Chit, (6) OVX-Sal + Est, and (7) OVX-Control (OVX-Co). Bone samples were extracted 48 hours after the final session. Two-way ANOVAs were used to determine differences in intervention effects between groups. The alpha level was set to 0.05. Results: Ovariectomy (OVX) decreased bone tissue expression of alkaline phosphatase (ALP) and osterix (OSX) while increasing peroxisome proliferator-activated receptor gamma (PPAR-γ) gene expression. Ovariectomy also decreased the number of osteocytes and osteoblasts while increasing the number of osteoclasts. Resistance training (RT) and Vit D + Ca++ + Chit intake increased bone tissue expression of ALP, OSX, and PPAR-γ gene expression. Additionally, RT and Vit D + Ca++ + Chit supplementation increased the number of osteocytes and osteoblasts and decreased the number of osteoclasts. Conclusions: The combined interventions had synergistic effects compared to each intervention separately on ALP, osteocyte, osteoblast, and osteoclast observations. Therefore, combining RT with Vit D + Ca++ + Chit could be a non-pharmacological approach to address bone turnover alterations caused by OVX.