Search Results (52)

Background/Objectives: Long-distance runners with exercise-induced hypertension (EIH) are at increased risk for cardiovascular complications. Although blood flow restriction (BFR) training has shown promise in improving vascular function, hemodynamic response, and cardiorespiratory fitness, its effects in EIH runners remain understudied. This study aimed to evaluate the effects of BFR training on cardiovascular responses and exercise performance in this population as a potential non-pharmacological therapy. Methods: Middle-aged male long-distance runners aged 40–65 with peak systolic blood pressure (SBP) ≥ 210 mmHg during graded exercise testing were randomly assigned to either a BFR group (n = 18) or a non-BFR control group (n = 15) using a computer-generated random sequence. There were no significant differences in baseline characteristics between the groups. Both groups performed aerobic training at 40–60% HRR for 20 min twice weekly for 8 weeks. SBP, diastolic blood pressure (DBP), rate pressure product (RPP), ventilatory threshold (VT), VO_₂max, and perceived exertion were assessed before and after the intervention at rest, during exercise, and during recovery. Results: Compared to the non-BFR group, the BFR group showed statistically significant reductions in resting and maximal SBP and DBP (p < 0.05), along with significant increases in VO_₂max and VT (p < 0.05). During submaximal exercise and post-exercise recovery, SBP and RPP were significantly lower in the BFR group (p < 0.05). The reductions in maximal SBP and DBP were significantly greater in the BFR group than in the control group. Conclusions: BFR training led to reduced myocardial workload and enhanced cardiovascular efficiency in male runners with EIH. These findings suggest that BFR training may be a viable non-pharmacological therapy for mitigating cardiovascular risks associated with EIH. Future studies should explore the long-term effects of BFR in broader populations and assess its applicability in clinical settings. Full article

Eventing is an Olympic equestrian discipline comprising dressage, cross-country, and show jumping, with the cross-country phase imposing the greatest physical demands on horses. This study presents a composite model to estimate energy expenditure during the cross-country phase, integrating physiological data (heart rate-derived $V{O}_2$ and lactate-based anaerobic estimates) with external workload indicators (GPS-derived speed, elevation, and course complexity). Model development was based on 691 rides from 256 horses across 232 events at 2-star to 5-star competition levels. The analysis showed that terrain, speed variability, and acceleration, largely shaped by course design, significantly affect energy expenditure. Aerobic and anaerobic contributions to power output varied by speed, format, and competition level. The model explained 29% of variance in power output and 91% when accounting for random effects, demonstrating the influence of both external and individual factors. Short-format events exhibited higher anaerobic contributions than long-format events. While the competition level had a modest effect, it reflected increasing technical difficulty and jump size. These findings underline the importance of incorporating both physiological responses and course characteristics in energy assessments. The model supports more targeted conditioning, enhances performance monitoring, and contributes to improved equine welfare by providing a more accurate understanding of workload in cross-country competitions. Full article

Background: Post-COVID-19 syndrome (PCS) is defined as the persistence of symptoms 3 months after acute SARS-CoV-2 infection. The long-term prevalence and clinical progression of PCS has not been established. Our aim was to investigate the symptoms in PCS patients, explore the degree of physical activity, according to the fatigue severity score, and analyze its association with basic cardio-pulmonary exercise testing (CPET) parameters. Methods: A total of 192 subjects with history of SARSCoV-2 infection were included. They filled in the Chronic Fatigue Syndrome Questionnaire (CFSQ) and were divided into symptomatic and asymptomatic groups. Forty-seven had persistent post-COVID complaints—reduced physical capacity, fatigue, dyspnea, sleep disturbances, muscle pain. CPET was performed and the pathophysiological parameters in the different fatigue severity groups were compared. Results: Subjects with persistent long-term PCS were divided into two groups—mild (20) and moderate–severe (27), depending on the CFSQ score; forty-eight PCS subjects without complaints served as a control group. The average period between the acute illness and the study was 1028 ± 214 days. Subjects with moderate–severe PCS had more symptoms during CPET (73.6% vs. 24.8% vs. 17.4%), as compared to mild/asymptomatic. The rate of perceived effort was subjective and did not correspond to the workload, heart, or breathing rate in the symptomatic group. These subjects were unable to reach the anaerobic threshold, compared to mild/asymptomatic subjects (51.8% vs. 25%, vs. 12.5%). Patients with moderate–severe PCS showed lower peak VO₂ (24.13 ± 6.1 mL/min/kg vs. 26.73 ± 5.9 mL/min/kg, vs. 27.01 ± 6.3 mL/min/kg), as compared to mild/asymptomatic subjects. Conclusions: Long-term PCS is still present in up to 24% of the general population, more than thirty months after the acute episode. It is characterized by increased perception of symptom burden and diminished aerobic metabolism. A third of the long-term PCS exhibit lower cardio-respiratory fitness, independently from the severity of the symptoms. Full article

Water treadmill (WT) exercise is gaining popularity among equine athletes as it allows for increased workload through the resistance posed by water. However, the effect of an artificial river (AR), which further increases this resistance, on equine fitness indicators has not yet been investigated. This study aimed to determine whether WT exercise with varying water depths and the presence of an AR influences physiological response indicators. Fifteen school horses (n = 15) underwent five treadmill exercise sessions: on a dry treadmill (DT), in fetlock-depth water with and without AR, and in carpal-depth water with and without AR. Physiological responses were assessed pre-exercise, during the highest workload, and at 30 min and 24 h post-exercise by measuring heart rate (HR), blood lactate concentration (LAC), red blood cell count (RBC), hemoglobin concentration (HGB), and the activity of three serum enzymes: creatine phosphokinase (CK), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH). HR and LAC increased significantly (p < 0.0001) from the pre-exercise resting state to the highest workload time point during treadmill exercise, regardless of session type. During the carpal-depth WT+AR session, horses achieved a fitness level characterized by the highest HR (p < 0.0001), LAC (p < 0.0001), and LDH activity (p = 0.001). Thus, horses’ physiological responses to walking on a WT with AR differ from those observed on a DT and a WT without AR. WT exercise with AR represents a low-to-moderate intensity aerobic workload for horses, which increases with water depth from fetlock to carpal levels. However, further research is required to evaluate its inclusion in training or rehabilitation programs for athletic horses and its potential beneficial effects. Full article

The heart rate slow component (_scHR) is an intensity-dependent HR increment that emerges during constant exercises, partially dissociated from metabolism ($\dot{\mathrm{V}}$O₂). The _scHR has been observed during constant-workload exercise in young and older adults. Unless this _scHR is accounted for, exercise prescription using HR targets lead to an undesired reduction in metabolic intensity over time. Purpose: The purpose of this study is to characterize _scHR across intensities, sex, and age to develop and validate a predictive equation able to maintain the desired metabolic stimulus over time in a constant aerobic exercise session. Methods: In our study, 66 individuals (35 females; 35 ± 13 yrs) performed the following: (i) a ramp-test for respiratory exercise threshold (GET and RCP) and maximal oxygen uptake ($\dot{\mathrm{V}}$O_2max) detection, and (ii) 6 × 9-minute constant exercises at different intensities. The _scHR was calculated by linear fitting from the fifth minute of exercise (bpm⋅min⁻¹). A multiple-linear equation was developed to predict the _scHR based on individual and exercise variables. The validity of the equation was tested on an independent sample by a Pearson correlation and Bland–Altman analysis between the measured and estimated HR during constant exercises. Results: The _scHR increases with intensity and is larger in males (p < 0.05). A multiple-linear equation predicts the _scHR based on the relative exercise intensity to RCP, age, and sex (r² = 0.54, SEE = 0.61 bpm⋅min⁻¹). _scHR (bpm⋅min⁻¹) = −0.0514 + (0.0240 × relative exercise intensity to RCP) − (0.0172 × age) − (0.347 × Sex (males = 0 and females score = 1)). In the independent sample, we found an excellent correlation between the measured and estimated HR (r² = 0.98, p < 0.001) with no bias (−0.01 b·min⁻¹, z-score= −0.04) and a fair precision (±4.09 b·min⁻¹). Conclusions: The dynamic of the _scHR can be predicted in a heterogeneous sample accounting for the combined effects of relative intensity, sex, and age. The above equation provides the means to dynamically adapt HR targets over time, avoiding an undesired reduction in the absolute and relative training load. This strategy would allow the maintenance of the desired metabolic stimulus ($\dot{\mathrm{V}}$O₂) throughout an exercise session in a heterogeneous population. Full article

Background: Brussels chicory affluent in phenolic acids could inhibit atherosclerosis; however, its effects on exercise performance and post-exercise recovery are unknown. We hypothesized that Brussels chicory could enhance exhaustive aerobic exercise performance and post-exercise recovery by promoting lactate oxidation. Methods: This is a single-blind, randomized, placebo-controlled two-way cross-over trial involving 32 untrained college students (men 18) who consumed either Brussels chicory juice (100 g of Brussels chicory containing ~130 mg phenolic acids and 180 mL fresh milk) or placebo (180 mL fresh milk) for 7 days with a 2-week washout period. On the 7th day, participants received a short-term, progressive workload, high-intensity, exhaustive aerobic exercise with the Bruce protocol. Time to exhaustion and blood lactate were evaluated after exercise. C2C12 myotubes were treated with Brussels chicory phenolic acids (0.625–10 μM) to evaluate these effects on lactate metabolism and lactate dehydrogenase A (LDHA) and B (LDHB), two enzymes responsible for lactate biosynthesis and oxidation, respectively. Results: Brussels chicory consumption increased time to exhaustion by 8.3% and 12.2% for men and women participants, respectively. This administration also promoted post-exercise recovery, evidenced by a reduction in blood lactate (14.5% for men and 10.6% for women). In C2C12 myotubes, Brussels chicory protocatechuic acid and caffeic acid did not affect LHDA-mediated lactate production, whereas these compounds dose-dependently promoted LDHB-mediated lactate oxidation through an enrichment of mitochondria LDHB. Conclusions: Dietary supplementation with Brussels chicory may enhance short-term, progressive workload, high-intensity, exhaustive aerobic exercise performance and post-exercise recovery in humans, possibly by accelerating LDHB-mediated lactate oxidation. Full article

To establish the capacity of absolute maximum strength and relative to body mass (BM) in deadlift (DL) and squat (SQ) exercises to estimate the maximum anaerobic running performance (MART) and maximum aerobic power (V_Peak), among individuals stratified into high (HS) vs. low strength score (LS). The sum of workloads (DL+SQ) was also analyzed and cross-validation was tested. Thirty-four students performed five visits in the first phase. In the first three visits the following were performed: sample characterization and consistency analysis of the maximum repetition (RM) for DL and SQ. Participants were stratified based on DL and SQ relativized by BM (DL/BM and SQ/BM). In the last two visits, MART and V_Peak were tested. Linear regression for HS participants did not predict MART for all strength measures. In contrast, the regressive model was significant for DL (R² = 0.482; p = 0.002), DL/BM (R² = 0.764; p < 0.001), SQ (R² = 0.357; p = 0.011) and SQ/BM (R² = 0.644; p < 0.001) in LS participants, compared to MART performance. For V_Peak, linear regression also did not demonstrate an association for all strength measures in HS participants. However, SQ (R² = 0.309; p = 0.021), DL/BM (R² = 0.343; p = 0.013) and SQ/BM (R² = 0.618; p < 0.001) were able to predict V_Peak. The prediction from the sum of the DL+SQ produced an association for MART (R² = 0.451; p = 0.003) and V_Peak (R² = 0.273; p = 0.031) in LS participants. In the second phase of the study, 17 participants performed cross-validation by testing the prediction equations. The same methodological procedures were performed for this phase, but only LS participants were tested. The Wilcoxon test compared real MART vs. predicted for DL (p = 0.02) and SQ (p = 0.043), showing differences, but not for DL/BM (p = 0.051) and SQ/BM (p = 0.093). The Wilcoxon test also showed differences for real V_Peak vs. predicted for DL/BM (p = 0.002), SQ (p = 0.019) and SQ/BM (p = 0.05). The MART predictive equation based on DL+SQ did not show differences (p = 0.148), but the same did not occur for V_Peak based on DL+SQ (p = 0.008). Maximum strength did not show predictive capacity in HS participants. However, it was significant for LS participants. DL showed greater predictive prominence for MART. In contrast, for V_Peak, SQ/BM satisfactorily explained the variations in running performance (61%). The predictive equations of MART by DL/BM and SQ/BM were shown to be accurate, as well as DL+SQ to predict MART. Full article

Wildland firefighting is physically and mentally demanding. The aerobic capacity of firefighters is important due to the demands of the activity and the associated occupational risks. The main objectives of this study were to identify and characterise the physically demanding tasks undertaken by volunteer firefighters during wildland fires (real work conditions). A total of 125 firefighters replied to a survey about sociodemographic, biometric data, and work fitness assessment. A group of 23 was evaluated in a physical stress test using a VO_2peak protocol to determine maximum oxygen consumption and ventilatory thresholds. The physical demands and physiological responses were collected during the operations at the firefront (n = 21). The results revealed that wildland firefighting entails physical demands that exceed established reference values, with maximum oxygen uptake exceeding 40%. The cardiovascular strain is particularly notable in tasks performed near the firefront, reflecting fatigue. The physical and cardiac demands associated with forest fire fighting have been demonstrated to contribute to occupational illnesses with prolonged exposure. This study underscores the imperative for interventions to enhance the identification and real-time monitoring of physiological parameters to enhance firefighters’ overall health and well-being. Full article

The purpose of this study was to compare the workload of a maximal treadmill test (TREAD) and a fire suppression task (BURN) in firefighters and to examine their relationships to fitness as measured by body mass index (BMI), percent body fat (BF%), and peak aerobic capacity (VO_2PEAK). The amount of time spent in the heart rate (HR) intensity ranges of 50–59% HR_MAX (ZONE1), 60–69% HR_MAX (ZONE2), 70–79% HR_MAX (ZONE3), 80–89% HR_MAX (ZONE4), and ≥90% HR_MAX (ZONE5) quantified the workload as the Edward’s Training Impulse for TREAD (ETRIMP_TREAD) and BURN (ETRIMP_BURN). The ETRIMP_TREAD was significantly less than ETRIMP_BURN. For TREAD, ZONE5 > ZONE2 and ZONE3. For BURN, ZONE4 > ZONE1, ZONE2, and ZONE5 > ZONE1, ZONE2, and ZONE3. A lower BF% and greater VO_2PEAK were related to a greater ETRIMP_TREAD and unrelated to ETRIMP_BURN. For BURN only, a lower BF% and greater VO_2PEAK were related to less time in ZONE5. BMI was unrelated to all workload measures. Laboratory-based maximal exercise testing does not adequately reflect the workload of simulated fire suppression and therefore may not be indicative of firefighter readiness to meet job demands. Less-fit firefighters rely on higher cardiovascular intensities to complete the same workload, and practitioners should consider this when selecting strategies to reduce job-associated cardiovascular risk. Full article

Basketball involves frequent high-intensity movements requiring optimal aerobic power. Altitude training can enhance physiological adaptations, but research examining its effects in basketball is limited. This study aimed to characterize the internal/external workload of professional basketball players during preseason and evaluate the effects of altitude and playing position. Twelve top-tier professional male basketball players (Liga Endesa, ACB; guards: n = 3, forwards: n = 5, and centers: n = 4) participated in a crossover study design composed of two training camps with nine sessions over 6 days under two different conditions: high altitude (2320 m) and sea level (10 m). Internal loads (heart rate, %HR_MAX) and external loads (total distances covered across speed thresholds, accelerations/decelerations, impacts, and jumps) were quantified via wearable tracking and heart rate telemetry. Repeated-measures MANOVA tested the altitude x playing position effects. Altitude increased the total distance (+10%), lower-speed running distances (+10–39%), accelerations/decelerations (+25–30%), average heart rate (+6%), time in higher-intensity HR zones (+23–63%), and jumps (+13%) across all positions (p < 0.05). Positional differences existed, with guards accruing more high-speed running and centers exhibiting greater cardiovascular demands (p < 0.05). In conclusion, a 6-day altitude block effectively overloads training, providing a stimulus to enhance fitness capacities when structured appropriately. Monitoring workloads and individualizing training by playing position are important when implementing altitude training, given the varied responses. Full article

Chronic non-specific low back pain (CNSLBP) is a highly prevalent musculoskeletal condition that has a great socioeconomic impact on health systems. Instead of focusing on mechanical causes and direct workload in the development of CNSLBP, genetics, psychosocial environment, lifestyle and quality of life are coming to the forefront in its approach. The main objective was to analyze whether interventions aimed at modifying lifestyle can be effective in improving pain intensity and functional disability in CNSLBP. A search in PubMed, Web of Science, Scopus and SportDiscus databases was performed. Both a univariate and a multivariate network meta-analysis were applied with the difference pre/post-treatment. A total of 20 studies were included for qualitative analysis, of which 16 were randomized clinical trials with a moderate–high methodological quality and were part of the quantitative analysis. The interventions that had the greatest effect in reducing pain intensity were cognitive therapy combined with functional exercise programs, lumbar stabilization exercise and resistance exercise; meanwhile, for functional disability, they were functional exercise programs, aerobic exercise and standard care. In conclusion, a multimodal intervention aimed at changing one’s lifestyle that encompasses cognitive, behavioral, and physical aspects seems to be highly effective in improving pain intensity and functional disability caused by CNSLBP; however, it is not yet known if these improvements are maintained in the long term. Full article

Background and Aims: The worldwide aging population is expanding, with more individuals living into their 80s. Physiological functions decline gradually with age, compounded by sedentary lifestyles. Incorporating physical activity into daily routine is crucial for maintaining independence. This study aimed to assess a periodized high-intensity aerobic training program (PEZO-BT) in octogenarians, focusing on submaximal ergospirometry effects. Methods: A total of 48 non-frail octogenarian subjects (12 females, 36 males) were randomized into control and intervention groups. All subjects underwent submaximal cardiopulmonary exercise testing with gas analysis at baseline, stopping after the respiratory compensation point (RCP). Our intervention group completed a 14-week PEZO-BT aerobic training program. The outcomes were oxygen consumption at first ventilatory threshold (VO₂AT), ventilatory efficiency slope (VE/VCO₂), oxygen uptake efficiency slope (OUES), cardiorespiratory optimal point (COP), oxygen pulse change (ΔVO₂/HR) from anaerobic threshold (AT) to respiratory compensation point (RCP), and power output at anaerobic threshold (POAT). Results: Mixed ANOVA examined time and treatment effects. If significance emerged, post hoc t-tests were used to compare significances between groups. The homogeneity of variance was assessed using Levene’s test. Chi-square tests compared ergospirometry criteria and ventilatory performance within groups. The mean differences at post intervention were significant in VO₂AT (p < 0.001), VE/VCO₂ (p < 0.001), ΔVO₂/HR (p < 0.05), and POAT (p < 0.001), while OUES and COP were not significant (p > 0.05). However, clinical effects were observed in the entire intervention group. Conclusions: Training improved exercise capacity and workload. Overall, this periodic aerobic and high-intensity interval training (HIIT) program yielded significant improvements in cardiorespiratory fitness (CRF) in previously untrained octogenarians with and without comorbidities. The findings suggest implications for promoting long-term healthy aging. Full article

Introduction: Post-COVID-19 syndrome (PCS) is a multisystemic disorder marked by impaired physical performance as one lead symptom. Since it has been suggested that endurance training as part of medical rehabilitation may be effective in improving physical performance capacity in PCS, this study aimed to compare different modes of aerobic endurance training. Methods: A total of 110 PCS patients (49.3 ± 11.8 years; 38% women; time after infection = 260.2 ± 127.5 days) underwent detailed clinical screening including symptom-limited cardiopulmonary exercise testing at admission and after 4–6 weeks of inpatient medical rehabilitation. Questionnaires were used to assess disease perception. Patients performed controlled isocaloric cycle ergometer training (3–5 sessions/week; 18 min) as either continuous training (CT) at 50% of maximal workload or as interval training (IT; load = 60%, relief = 30%). Outcomes of PCS patients were compared to coronary artery disease patients (CAD; n = 96) to evaluate overall training effectiveness. Results: Training participation was comparable between the groups, with no indication of training-specific exercise-induced fatigue. Overall, PCS patients improved significantly by a mean of 6.8 ± 12.1% for W at VT1; 3.1 ± 10.0% for VO₂ at VT1; 5.5 ± 14.7% for O₂ pulse at VT1; 7.5 ± 15.0% for W at VO_2peak; 2.7 ± 11.0% for VO_2peak and 4.6 ± 12.4% for O₂ pulse at VO_2peak (all p < 0.05) with no significant differences between groups (p > 0.05). Both groups showed reduced levels of fatigue, anxiety, and depression as well as improved quality of life and wellbeing (all p < 0.05). Compared to guideline-based cardiac rehabilitation, PCS patients showed a similar improvement in workload and oxygen uptake compared to CAD patients. Conclusion: PCS patients benefit from aerobic endurance training performed as moderate continuous or interval training as part of a medical rehabilitation program in terms of improved physical exercise capacity and disease perception. The results for PCS patients are comparable to the guideline-based rehabilitation of CAD patients. Full article

The aim of study was to evaluate the effects of interval training performed in hypoxia on aerobic capacity and second ventilatory threshold in young, untrained men. Participants (n = 48) were randomly divided into a control group and two groups performing the same interval training (three times a week for 4 weeks) in normoxia (200 m asl) (NT) and in hypoxia (IHT) (3000 m asl, FIO₂ = 14.4%). In the incremental test, maximal oxygen uptake (VO₂max) was measured and the first (VT1) and second (VT2) ventilatory thresholds and the maximal power output (Pmax) were determined for each participant. The training workloads of the efforts corresponded to the workload at VT2 (effort) and VT1 (active recovery). Training in both normoxia and hypoxia significantly increased absolute VO₂max (p = 0.02, ES = 0.51 and p = 0.002, ES = 0.47, respectively). In comparison to NT, only IHT significantly (p < 0.001; ES = 0.80) improved Pmax, as well as power at VT2 (p = 0.02; ES = 0.78). The applied IHT was effective in improving Pmax and power at VT2, which was not observed after training in normoxia. Full article

Transcatheter aortic valve implantation (TAVI) improves event-free survival in patients with severe aortic stenosis, but patients’ exercise capacity remains poor after the procedure. Therefore, we sought to compare the effects of a supervised center-based exercise training program and unsupervised exercise routine on exercise capacity and vascular function in patients after TAVI. Patients were randomized to either center-based exercise training (12–24 sessions of combined aerobic and low-weight resistance training twice weekly for 8–12 weeks) or an unsupervised home-based exercise routine (initial appraisal with detailed recommendations and monthly follow-up). Exercise capacity (cardiopulmonary testing) and vascular function (ultrasonographic measurement of flow-mediated vasodilation (FMD) and arterial stiffness) were assessed at the baseline and after the study period. We included 23 patients (mean age of 81 years, 61% women), with higher-than-expected drop-out rates (41%) because of the coronavirus-19 pandemic outbreak. Exercise capacity improved over time, irrespective of the intervention group: 0.09 mL/min/kg increase in peak oxygen uptake (95% CI [0.01–0.16]; p = 0.02), 8.2 Watts increase in workload (95% CI [0.6–15.8]; p = 0.034), and 47 s increase in cumulative exercise time (95% CI [5.0–89.6]; p = 0.029). A between-group difference in change over time (treatment effect) was detected only for FMD (4.49%; 95% CI [2.35; 6.63], p < 0.001), but not for other outcome variables. Both supervised and unsupervised exercise training improve exercise capacity and vascular function in patients after TAVI, with supervised exercise training possibly yielding larger improvements in vascular function, as determined by FMD. Full article