In an increasingly aging and overweight population, osteoporosis and type 2 diabetes (T2DM) are major public health concerns. T2DM patients experience prejudicial effects on their bone health, affecting their physical capacity. Exercise in hypoxia (EH) and a low-carbohydrate diet (LCD) have been suggested for therapeutic benefits in T2DM, improving bone mineral content (BMC) and glycemic control. This study investigated the effects of EH combined with an LCD on body composition and functional and physiologic capacity in T2DM patients. Older T2DM patients (n = 42) were randomly assigned to the following groups: (1) control group: control diet + exercise in normoxia; (2) EH group: control diet + EH; (3) intervention group: LCD + EH. Cardiopulmonary tests (BRUCE protocol), body composition (DEXA), and functional capacity (6MWT, handgrip strength) were evaluated. Body mass index (kg/m²) and body fat (%) decreased in all groups (p < 0.001). BMC (kg) increased in all groups (p < 0.001) and was significantly higher in the EH and EH + LCD groups (p < 0.001). VO_2peak improved in all groups (p < 0.001), but more so in the hypoxia groups (p = 0.019). Functional capacity was increased in all groups (p < 0.001), but more so in the EH group in 6MWT (p = 0.030). EH with and without an LCD is a therapeutic strategy for improving bone mass in T2DM, which is associated with cardiorespiratory and functional improvements.

To investigate the effect of an acute oral administration of pseudoephedrine (PSE) on muscle function, fatigue, and anaerobic power output. Healthy males (N = 10) and females (N = 10) were allocated to receive both a placebo and PSE (120 mg) using a randomized, double-blind, crossover experimental design. Each subject had their maximal voluntary contraction strength and fatigability measured for both handgrip and ankle dorsi-flexion. Following the strength measurements, a 30-second maximal cycle test was performed to determine lower extremity anaerobic power and fatigue. Plasma lactate was measured before and after exercise. There were no significant differences in any of the outcome variables between the placebo and PSE trials. These results demonstrated that a 120 mg dose of PSE did not enhance force production, time to fatigue, fatigue index, or power output in young men or women. Therefore, there does not appear to be an ergogenic benefit from the ingestion of 120 mg PSE in high-intensity exercise performance.

We investigated the effects of hypoxia on matched-severe intensity exercise and on the parameters of the power-duration relationship. Fifteen trained subjects performed in both normoxia and normobaric hypoxia (F_iO₂=0.13, ~3000 m) a maximal incremental test, a 3 min all-out test (3AOT) and a transition from rest to an exercise performed to exhaustion (T_lim) at the same relative intensity (80%∆). Respiratory and pulmonary gas-exchange variables were continuously measured (K5, Cosmed, Italy). T_lim test’s V̇O₂ kinetics was calculated using a two-component exponential model. V̇O₂max (44.1±5.1 vs. 58.7±6.4 ml.kg^-1.min^-1, p<0.001) was decreased in hypoxia. In T_lim, time-to-exhaustion sustained was similar (454±130 vs. 484±169 s) despite that V̇O₂ kinetics was slower (_τ1: 31.1±5.8 vs. 21.6±4.7 s, p<0.001) and the amplitude of the V̇O₂ slow component lower (12.4±5.4 vs. 20.2±5.7 ml.kg^-1.min^-1, p<0.05) in hypoxia. CP was reduced (225±35 vs. 270±49 W, p<0.001) but W’ was unchanged (11.3±2.9 vs. 11.4±2.7 kJ) in hypoxia. The changes in CP/V̇O₂max were positively correlated with changes in W’ (r = 0.58, p<0.05). The lower oxygen availability had an impact on aerobic related physiological parameters, but exercise tolerance is similar between hypoxia and normoxia when the relative intensity is matched despite a slower V̇O₂ kinetics in hypoxia. Received: 16 May 2020 Accepted: 23 July 2020 Publication Date: 18 January 2021 (online) © 2021. Thieme. All rights reserved. Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, Germany

Introduction: Training intensity and nutrition may influence adaptations to training performed in hypoxia and consequently performance outcomes at altitude. This study investigates if performance at simulated altitude is improved to a larger extent when high-intensity interval training is performed in normobaric hypoxia and if this is potentiated when combined with chronic dietary nitrate (NO₃⁻) supplementation.Methods: Thirty endurance-trained male participants were allocated to one of three groups: hypoxia (13% F_iO₂) + NO₃⁻; hypoxia + placebo; and normoxia (20.9% F_iO₂) + placebo. All performed 12 cycling sessions (eight sessions of 2*6 × 1 min at severe intensity with 1 min recovery and four sessions of 4*6*10 s all-out with 20 s recovery) during a 4-week period (three sessions/week) with supplementation administered 3–2.5 h before each session. An incremental exhaustion test, a severe intensity exercise bout to exhaustion (T_lim) and a 3 min all-out test (3AOT) in hypoxia (F_iO₂ = 13%) with pulmonary oxygen uptake (V˙O₂), V˙O₂ kinetics, and changes in vastus lateralis local O₂ saturation (SmO₂) measured were completed by each participant before and after training.Results: In all tests, performance improved to the same extent in hypoxia and normoxia, except for SmO₂ after T_lim (p = 0.04, d = 0.82) and 3AOT (p = 0.03, d = 1.43) which were lower in the two hypoxic groups compared with the normoxic one. Dietary NO₃⁻ supplementation did not bring any additional benefits.Conclusion: Performance at simulated altitude was not improved to a larger extent when high-intensity interval training was undertaken in normobaric hypoxic conditions, when compared with normoxic training. Additionally, dietary NO₃⁻ supplementation was ineffective in further enhancing endurance performance at simulated altitude.

Background/Objectives: Type 2 diabetes mellitus (T2DM) is a chronic condition marked by hyperglycemia, which can affect metabolic, vascular, and hematological parameters. A low-carbohydrate, high-fat (LCHF) diet has been shown to improve glycemic control and blood pressure regulation. Exercise in hypoxia (EH) enhances insulin sensitivity, erythropoiesis, and angiogenesis. The combination of LCHF and EH may offer a promising strategy for managing T2DM and hypertension (HTN), although evidence remains limited. This study aimed to assess the effects of an eight-week normobaric EH intervention at 3000 m simulated altitude combined with an LCHF diet on hematological and lipid profiles, inflammation, and blood pressure in older patients with T2DM and HTN. Methods: Forty-two diabetic patients with HTN were randomly assigned to three groups: (1) control group (control diet + exercise in normoxia), (2) EH group (control diet + EH), and (3) intervention group (EH+LCHF) Baseline and eight-week measurements included systolic, diastolic, and mean blood pressure (SBP, DBP, MAP), hematological and lipid profiles, and inflammation biomarkers. Results: Blood pressure decreased after the intervention (p < 0.001), with no significant differences between groups (SBP: p = 0.151; DBP: p = 0.124; MAP: p = 0.18). No differences were observed in lipid profile or C-reactive protein levels (p > 0.05). Mean corpuscular hemoglobin (MCH) increased in the EH group (p = 0.027), while it decreased in the EH+LCHF group (p = 0.046). Conclusions: Adding hypoxia or restricting carbohydrates did not provide additional benefits on blood pressure in T2DM patients with HTN. Further elucidation of the mechanisms underlying hematological adaptations is imperative. Trial registration number: NCT05094505.

Background: Cardiovascular disease is the leading cause of mortality associated with diabetes, which is characterized by chronic hyperglycemia. Low-carbohydrate diet has gained popularity as an intervention in patients with type 2 diabetes mellitus, acting to improve glycemic profile and serum lipids. In its turn, exercise in hypoxia induces specific adaptations, mostly modulated via hypoxia-induced transcription factor signaling cascade, which increases with exposure to altitude, and promotes angiogenesis, glycogen supply, glucose tolerance, and raises GLUT-4 expression. Aim: Given that hyperglycemia decreases HIF-1α and it is better controlled when following a low-carbohydrate diet, this study aims to examine the hypothesis that a combination of both low-carbohydrate diet and chronic exercise in hypoxia in type 2 diabetes mellitus is associated with improved glycemic control and cardiovascular parameters, whose protocol is described. Methods: Patients with type 2 diabetes mellitus ( n = 48) will be recruited and randomized into one of the three groups: (a) Control group: Control diet (low-fat and moderate-carbohydrate diet) + exercise in normoxia; (2) exercise in hypoxia group: Control diet + exercise in hypoxia; (3) intervention group: Low-carbohydrate diet (low-carbohydrate and high-fat diet) + exercise in hypoxia. Before and after 8 weeks of interventions, cardiopulmonary tests (Bruce protocol), body composition and blood pressure will be evaluated. Blood samples will be collected to measure hypoxia-induced transcription factor, C-reactive protein, glycemic and lipid profiles. Summary: This will be the first trial to examine the isolated and combined effect of chronic exercise in hypoxia and low-carbohydrate diet in type 2 diabetes mellitus. This trial will help to fill a significant research gap, guide future research and contribute to the combined nutrition and exercise approach to type 2 diabetes mellitus.