Exercise Intensity Research Articles

Effectiveness of Aerobic Training for Adverse Symptoms Related to Chemotherapy During Treatment: Protocol for a Randomized Controlled Trial With Cost-Effectiveness Assessment.

One strategy to prevent adverse effects resulting from chemotherapy treatment is to perform physical exercises during treatment. However, there is still no consensus on the best type and intensity of exercise, nor when it should be started. Most studies have been carried out in patients with breast cancer, usually a few weeks after starting chemotherapy, on an outpatient basis 2 to 3 times a week. The main differences in our study are that we carried out physical training in hospitalized patients undergoing a cycle of chemotherapy for cancer treatment and that this training was carried out 5 times a week and was not restricted to a specific type of cancer. We aimed to evaluate the effects of aerobic training on symptoms related to chemotherapy (nausea, vomiting, asthenia, and sensation of weakness), fatigue, mobility, clinical complications, and length of hospital stay of patients during the drug treatment cycle. We also evaluated patient satisfaction with the proposed intervention, the adverse effects of aerobics training, and the cost-effectiveness of this intervention. This is a controlled and randomized trial with blinded evaluation that will include 94 hospitalized patients with cancer for 1 or more cycles of chemotherapy. The intervention group will perform aerobic training during a cycle of chemotherapy. The control group will receive a booklet with guidelines for staying active during the hospitalization period. The groups will be compared using a linear mixed model for fatigue, mobility, and chemotherapy-related symptoms before and after the intervention. The length of hospital stay will also be compared between groups using Kaplan-Meier survival analysis. The incidence of complications will be compared using the χ2 test. Cost-effectiveness and cost-utility analyses will be performed for the impact of exercise and quality-adjusted life years with the EQ-5D-3L-21 quality of life trials. The implementation variables (acceptability, suitability, and feasibility) will be evaluated by frequencies. The clinical trial registration was approved in March 2023. Recruitment and data collection for the trial are ongoing, and the results of this study are likely to be published in late 2025. Chemotherapy has side effects that negatively impact the quality of life of patients with cancer. Aerobic exercise can reduce these side effects in a simple and inexpensive way. The field of work of physical therapists could be expanded to oncology if the intervention works. Registro Brasileiro de Ensaios Clínicos RBR-6b4zwx3; https://tinyurl.com/39c4c7wz. DERR1-10.2196/60828.

Heat Suit Training Preserves the Increased Hemoglobin Mass Following Altitude Camp in Elite Cyclists.

Altitude training is a common strategy used with the intent to increase hemoglobin mass (Hbmass) in athletes. However, if the Hbmass is increased during altitude camps it seems to decline rapidly upon returning to sea level. This study aimed to examine the efficacy of three weekly heat training sessions over a 3.5-week period following a 3-week altitude camp, on the maintenance of Hbmass in elite cyclists. Eighteen male cyclists (maximal oxygen consumption: 76 ± 5 mL·min-1·kg-1) underwent a 3-week altitude training camp at ~2100 m above sea level. After the camp, participants were divided into one group performing three weekly heat sessions that was subtracted from their usual training (HEAT) while the other continuing usual training (CON). Training characteristics were recorded during the intervention, while hematological measurements were recorded before the camp as well as two days and 3.5-weeks after the altitude camp. The 3-week altitude camp led to an overall increase in total Hbmass of 4.1%. Afterwards, HEAT maintained Hbmass (0.2%, p = 0.738), while CON group experienced a significant reduction (-3.3%, p < 0.001) (ΔHEAT vs. ΔCON, p < 0.001). Moreover, HEAT increased plasma volume (PV) by 11.6% (p = 0.007) and blood volume (BV) by 5.8% (p = 0.007), whereas CON only showed an increase in PV (5.5%, p = 0.041). Exercise intensity and training load were not different between groups during the maintenance period. This study suggests that incorporating three weekly heat training sessions into the usual training routine preserves a moderately increased Hbmass in elite cyclists following an altitude camp.

Human movement monitoring system for classification of strength exercises and verification of their execution technique

Human movement analysis is critical to optimizing sports training and influencing exercise intensity and effectiveness. In the age of modern technology, more and more advanced systems are emerging to support coaches and expand the range of analysis performed. This article aims to verify that artificial intelligence, together with machine learning algorithms, can accurately classify exercises in a dynamic gym environment and effectively assess the correctness of their performance. For the initial analysis of movement, the Google MediaPipe Pose model was used, which was responsible for detecting the human silhouette and determining the coordinates of the position of critical joints. Based on these coordinates, the angles between each joint were calculated, and then their sequences were further analyzed. The sequences were analyzed using the following three algorithms: support vector machine (SVM), dense neural network, and LSTM recurrent network. As a result, the system based on recurrent LSTM networks achieved the best prediction efficiency of approximately 98%, enabling accurate exercise classification. Subsequently, verification of the activities' correctness was also carried out, and the system, based on recursive LSTM networks, again achieved the best efficiency, this time equal to 96% on average for all exercises. On this basis, it was concluded that the discussed approach enables practical analysis of human movement, which can significantly improve training methods and facilitate coaching work.

Effects of Weight Loss and Weight Maintenance on Lipoprotein Insulin Resistance Scores in Adults with Overweight and Obesity.

Background: An elevated lipoprotein insulin resistance (LP-IR) score corresponds to insulin resistance in adults with overweight and obesity, yet data are lacking regarding the impact of exercise interventions on LP-IR. The purpose of this secondary analysis was to evaluate the effects of a weight loss and weight maintenance intervention on LP-IR score in adults with overweight and obesity. Methods: Thirty sedentary adults with overweight and obesity completed a 10-week OPTIFAST® weight loss program with supervised aerobic exercise to achieve clinical weight loss (CWL) (≥7% from baseline). Aerobic exercise volume increased weekly until 700 MET min/week was reached. Participants who reached CWL were randomized to groups at volumes at either physical activity (PA-REC) or weight maintenance (WM-REC) recommendations (weeks 11-28). Plasma blood samples were analyzed via nuclear magnetic resonance spectroscopy at baseline, after weight loss (week 10), and following weight maintenance (week 28). Results: Following the weight loss phase, on average, participants significantly (p < 0.001) reduced LP-IR score (-12.1 ± 13.5), body weight (-8.9 ± 2.7%), and waist circumference (-7.7 ± 4.1 cm). During the weight maintenance phase, there were no changes in LP-IR score between exercise groups (PA-REC: 4.1 ± 13.6; WM-REC: -2.0 ± 11.2; P = 0.7). The PA-REC group had improvements in LP-IR score from baseline (49.8 ± 24.6 to 36.6 ± 27.6, P < 0.001), yet there were no within-group changes during the weight maintenance phase (P > 0.05). Conclusion: LP-IR score improved during weight loss in adults with overweight and obesity and were sustained during the weight maintenance phase in the PA-REC group. Aerobic exercise at least at minimum guidelines following CWL can preserve LP-IR score improvements and may indicate a reduced T2DM risk in adults with overweight and obesity.

Acute salivary antimicrobial peptide secretion response to different exercise intensities and durations.

Antimicrobial peptides, key players of innate mucosal immunity in the oral cavity, exert antibacterial and bacteriolytic effects. This study aimed to clarify the effects of acute exercise at different intensities and durations on salivary antimicrobial peptide levels. In a randomized crossover trial, 14 young healthy untrained men performed intensity trials (cycling at 35%, 55%, and 75% of maximal oxygen uptake [VO2max] for 30 min) and duration trials (cycling at 55% VO2max for 30, 60, and 90 min). Saliva samples were collected at baseline and 0 and 60 min after exercise. In intensity trials, the change in salivary Lactoferrin levels from baseline to 0 min after 30-min exercise was greater at 75% VO2max exercise intensity compared to that at 35% VO2max. Furthermore, the change in salivary human beta defensin-2 (HBD-2) levels was greater at 75% VO2max compared to that at 35% and 55% VO2max. Salivary Lysozyme levels increased after exercise, independent of exercise intensity. However, salivary LL-37 levels did not change after exercise at any intensity. Additionally, in duration trials, the change in salivary levels of LL-37 and HBD-2 from baseline to 0 min after exercise at 55% VO2max was greater after 60 min and 90 min of exercise compared to that after 30 min of exercise. However, salivary Lactoferrin and Lysozyme levels increased after exercise, independent of exercise duration. Our findings suggest that secretory responses to acute exercise with exercise intensity and duration differ among salivary antimicrobial peptides.

Gene Expression of Neurogenesis Related to Exercise Intensity in a Cerebral Infarction Rat Model.

Regular exercise improves several functions, including cognition, in patients with stroke. However, the effect of regular exercise on neurogenesis related to cognition remains doubtful. We investigated the most effective exercise intensity for functional recovery after stroke using RNA sequencing following regular treadmill exercise. Photothrombotic cerebral infarction was conducted for 10-week-old male Sprague-Dawley rats (n = 36). A Morris water maze (MWM) test was performed before a regular treadmill exercise program (5 days/week, 4 weeks). Rats were randomly divided into four groups: group A (no exercise); group B (low intensity, maximal velocity 18 m/min); group C (moderate intensity, maximal velocity 24 m/min) and group D (high intensity, maximal velocity 30 m/min). After 4 weeks, another MWM test was performed, and all rats were sacrificed. RNA sequencing was performed with ipsilesional hippocampal tissue. On the day after cerebral infarction, no differences in escape latency and velocity were observed among the groups. At 4 weeks after cerebral infarction, the escape latencies in groups B, C, and D were shorter than in group A. The escape latencies in groups B and C were shorter than in group D. The velocity in groups A, B, and C was faster than in group D. Thirty gene symbols related to neurogenesis were detected (p < 0.05, fold change > 1.0, average normalized read count > four times). In the neurotrophin-signaling pathway, the CHK gene was upregulated, and the NF-κB gene was downregulated in the low-intensity group. The CHK and NF-κB genes were both downregulated in the moderate-intensity group. The Raf and IRAK genes were downregulated in the high-intensity group. Western blot analysis showed that NF-κB expression was lowest in the moderate-intensity group, whereas CHK and Raf were elevated, and IRAK was decreased in the high-intensity group. Moderate-intensity exercise may contribute to neuroplasticity. Variation in the expression of neurotrophins in neurogenesis according to exercise intensity may reveal the mechanism of neuroplasticity. Thus, NF-κB is the key neurotrophin for neurogenesis related to exercise intensity.

Precision and accuracy of four handheld blood lactate analyzers across low to high exercise intensities.

To evaluate the precision and accuracy in measured blood lactate concentrations among four commonly used handheld lactate analyzers compared to two stationary analyzers. Venous blood samples were taken at exercise intensities ranging from low to high. The blood lactate concentration was measured simultaneously with four pairs of handheld lactate analyzers (two new units of each brand: Lactate Plus, Lactate Pro2, Lactate Scout 4, and TaiDoc TD-4289), and compared with two stationary analyzers (Biosen C-Line and YSI Sport 1500). Measurements were repeated for a range of blood lactate concentrations (measured with Biosen) from 0.88 to 4.89mM with a median difference between measurements of 0.10 mM. The mean relative differences to the Biosen analyzer were 7% (Plus), 7% (Pro), 10% (Scout), 42% (Tai), and 32% (Ysi). The residual standard errors after linear regression against Biosen were 0.18 mM (Plus), 0.20 mM (Pro), 0.22 mM (Scout), 0.15 mM (Tai), and 0.06 mM (Ysi). Accordingly, a blood lactate concentration of 3mM measured with Biosen yielded 95% prediction intervals that were 0.72 mM (Plus), 0.80 mM (Pro), 0.87 mM (Scout), 0.60 mM (Tai), and 0.23 mM (Ysi) wide. Compared to our two stationary analyzers, the precision of the four handheld lactate analyzers evaluated in this study was poor. Among the four, Tai was the most precise; however, this analyzer had low accuracy with a substantial mean difference to the reference analyzer.

Walking performance differs between people with multiple sclerosis who perform distinct types of exercise.

Aim: To determine whether walking performance differed between people with multiple sclerosis (MS) who performed distinct types, volumesand intensities of exercise.Materials& methods: Forty-five people with relapsing-remitting MS performed two trials of the 2-minwalk test, one at a preferred speed and another at a fast speed. Gait metrics were measured by wireless inertial sensors. Participants reported the type (aerobic, resistance), volumeand intensity of exercise performed.Results: Walking speed reserve and gait variability were better in participants who performed combined aerobic and resistance exercises compared with those who performed aerobic-only exercise.Conclusion: Walking performance differs in people with mild MS disability based on the type and volume of exercise performed.

Biofeedback and Exercise Load Affect Accuracy of Tongue Strength Exercise Performance.

Rehabilitative exercises require precise movement coordination and target accuracy for optimal effectiveness. This paper explores the impact of tongue strength exercises (TSE) performance accuracy on exercise outcomes, adherence, and participant confidence and motivation. An 8-week randomized clinical trial included 84 typically aging participants divided into four groups defined by access to biofeedback (present/absent) and TSE intensity dosing (maximal/submaximal) during a home exercise program (HEP). Retention, training, and HEP accuracy were tracked at biweekly visits and during HEP for participants with access to a biofeedback device. Associations with tongue strength outcomes, participant factors, biofeedback, and intensity dosing were analyzed. Exercise accuracy measures did not contribute to tongue strength outcomes at the end of 8weeks. Increased training accuracy (less practice required to achieve competency) was associated with higher participant confidence and better adherence to the HEP. The presence of biofeedback was associated with reduced adherence but better retention accuracy, while maximal intensity was associated with improvements in all accuracy measures compared to submaximal intensity exercise. These findings in typically aging participants suggest the need for tailored approaches in swallowing-related exercise programs, given the effects of biofeedback and exercise intensity on motor learning and exercise retention. Accuracy performance and its effect on clinical outcomes warrants study in clinical populations with dysphagia and with various rehabilitative approaches.Trial Registration Clincialtrials.gov: NCT04809558.

Exercise Volume Provides New Insight into the Effects of Housing Systems on Chicken Body Conformation, Carcass Traits, Meat Quality, and Serum Biochemical Parameters.

This study aims to investigate the dynamic changes in daily step counts under different housing systems and further explore the effects of housing system on the body conformation, carcass traits, meat quality, and serum biochemical parameters of a Chinese indigenous chicken breed. At 60 d of age, 300 Jiuyuan Black male chickens with similar body weights in each housing system were further raised until the age of 150 d. At 90, 120, and 150 d of age, in both cage-reared and free-range systems, the top 20 chickens with the highest step counts measured using pedometers and the bottom 20 chickens with the lowest step counts were designated as the cage high-steps group (CHS), the cage low-steps group (CLS), the free-range high-steps group (FHS), and the free-range low-steps group (FLS), respectively. The results show that, at any age stage, the average daily steps (ADS) and total steps (TS) of the FHS group are significantly higher than the other three groups (p < 0.05). The TS of almost all groups showed an overall downward trend as the age increased. Increased exercise volume results in reduced shank length (90 d), breast width (90 d), and keel length (150 d) (p < 0.05). Only birds at 90 d of age from the FHS and FLS groups exhibited lower live body weight, carcass weight, half-eviscerated weight, eviscerated weight, breast muscle weight, leg muscle weight, and percentage of eviscerated weight than the CLS group (p < 0.05). Birds from the FHS group showed the highest heart weight values but the lowest abdominal fat weight values among these four groups (p < 0.05). Both the breast and leg muscle samples from the FHS group displayed higher dry matter and shear force than those from the CHS and CLS groups (p < 0.05). The FHS group displayed the lowest intramuscular fat among the four groups (p < 0.05). The creatine kinase (CK) and lactate dehydrogenase (LDH) levels in chickens of all age stages were almost observed to rise with increased physical activity. In conclusion, free-range chickens with more exercise volume exhibited an elevated heart weight and reduced abdominal fat but showed negative effects on some body measurements and carcass traits. These results can provide a theoretical basis for the selection of different housing systems for Chinese indigenous chickens.

Efficacy of Qigong Baduanjin on nutritional status and quality of life in patients on haemodialysis: study protocol for a prospective randomised controlled trial

IntroductionHaemodialysis (HD) patients usually engage in a low level of physical activities, which could impact the prognosis and mortality of this group. Fitness Qigong Baduanjin, a physical exercise from traditional...

The Role of Gut Microbiota in Different Types of Physical Activity and Their Intensity: Systematic Review and Meta-Analysis.

Intense exercise during training requires dietary modulation to support health and performance and differs in different types of activities. Diet, supplementation with prebiotics and probiotics, and, more recently, even physical activity can potentially improve health outcomes by modifying and protecting the gut microbiota. A systematic review and meta-analysis were conducted to investigate the modulation of gut microbiota in different types and intensities of physical activity and different lifestyles of athletes. The systematic review and meta-analysis were conducted according to the PRISMA guidelines, and the protocol was registered in PROSPERO (CRD42024500826). Out of 1318 studies, only 10 met the criteria for inclusion in the meta-analysis. The pilot study's meta-regression analysis highlights the role of type and intensity of exercise in changing the B/B (Bacillota/Bacteroidota) ratio (p = 0.001). As gut training becomes more popular among athletes, it is necessary to map interactions between microbiota and different types of physical activity, personalized diets, physical activities, and ergogenic supplements to enhance performance and athletic wellness.

The independent and combined effects of aerobic exercise intensity and dose differentially increase post-exercise cerebral shear stress and blood flow.

This research examined the impact of aerobic exercise intensity and dose on acute post-exercise cerebral shear stress and blood flow. Fourteen young adults (27±5years of age, eight females) completed a maximal oxygen uptake ( ) treadmill test followed by three randomized study visits: treadmill exercise at 30% of for 30min, 70% of for 30min and 70% of for a duration that resulted in caloric expenditure equal to that in the 30% visit (EqEE). A venous blood draw and internal carotid artery (ICA) ultrasound were collected before and immediately following exercise. ICA diameter and blood velocity were determined using automated edge detection software, and blood flow was calculated. Using measures of blood viscosity, shear stress was calculated. Aerobic exercise increased ICA shear stress (time: P=0.005, condition: P=0.012) and the increase was greater following exercise at 70% (∆4.1±3.5dyn/cm2) compared with 30% (∆1.1±1.9dyn/cm2; P=0.041). ICA blood flow remained elevated following exercise (time: P=0.002, condition: P=0.010) with greater increases after 70% (Δ268±150mL/min) compared with 30% (∆125±149mL/min; P=0.041) or 70% EqEE (∆127±177mL/min; P=0.004). Therefore, aerobic exercise resulted in both intensity- and dose-dependent effects on acute post-exercise ICA blood flow whereby vigorous intensity exercise provoked a larger increase in ICA blood flow compared to light intensity exercise when performed at a higher dose.

Barriers to and facilitators of improving physical activity and nutrition behaviors during chemotherapy for breast cancer: a sequential mixed methods study.

Use qualitative and quantitative methods to explore factors influencing the adoption of guideline-based physical activity (PA) and dietary recommendations among participants enrolled in a lifestyle intervention during and after chemotherapy for breast cancer. Among women with stage I-III breast cancer who participated in the intervention arm of the Lifestyle, Exercise, and Nutrition early after diagnosis (LEANer) trial, we used stratified, purposeful sampling to interview women who met both, one, or neither intervention goal after the 1-year intervention: (1) 150min/week moderate-to-vigorous intensity exercise via a self-reported PA questionnaire and (2) improved self-reported diet quality measured by the Healthy Eating Index-2015. Semi-structured interviews were audio-recorded, transcribed verbatim, and analyzed using thematic content analysis. The 29 women interviewed were 52 ± 11years old on average, with a mean body mass index of 29.6 ± 7.7kg/m2. Three themes emerged regarding aspects of the LEANer intervention that facilitated behavior change: (1) providing a conduit of trustworthy, timely, and personalized support and education; (2) shifting mindsets and enhanced understanding of the benefits of PA and nutrition during chemotherapy; and (3) fostering a sense of control and alternative focus. Factors described as hindering adoption of goals included: (1) adverse effects of chemotherapy and (2) competing priorities. Women reported the external support, tailored education, and experiencing the physical and mental benefits of the LEANer intervention facilitated the adoption of the interventions' behavioral goals. Addressing chemotherapy-related symptoms and competing priorities may facilitate adherence to lifestyle interventions during chemotherapy for breast cancer.

Familial Hypokalemic Periodic Paralysis Attack Following SARS‑Cov‑2 Infection: A Case Report

Familial hypokalemic periodic paralysis is a rare disorder that manifests manifests with the sudden onset of flaccid paralysis that is triggered by low levels of blood potassium, which can be caused by various factors such as, rest after intense exercise, or high-carbohydrate foods. This report presents cases of hypokalemic periodic paralysis attack triggered by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. A 29-year-old male patient was admitted with quadriparesis, fever, shortness of breath, and sever hypokalemia. The patient had a history of three episodes of Familial hypokalemic periodic paralysis (HPP). Diagnostic tests, such as chest computed tomography scan and polymerase chain reaction test, confirmed SARS-CoV-2 infection. The patient was treated with potassium chloride infusion, spironolactone, and remdesivir, and was eventually discharged from the hospital.in conclusion, SARS-CoV-2 infection can potentially exacerbate HPP and should be considered a risk factor for its occurrence.

Cortical response characteristics of passive, active, and resistance movements: a multi-channel fNRIS study.

This study aimed to explore the impact of exercise training modes on sensory and motor-related cortex excitability using functional near-infrared spectroscopy technology (fNIRS) and reveal specific cortical effects. Twenty participants with no known health conditions took part in a study involving passive, active, and resistance tasks facilitated by an upper-limb robot, using a block design. The participants wore functional near-infrared spectroscopy (fNIRS) devices throughout the experiment to monitor changes in cortical blood oxygen levels during the tasks. The fNIRS optode coverage primarily targeted key areas of the brain cortex, including the primary motor cortex (M1), primary somatosensory cortex (S1), supplementary motor area (SMA), and premotor cortex (PMC) on both hemispheres. The study evaluated cortical activation areas, intensity, and lateralization values. Passive movement primarily activates M1 and part of S1, while active movement mainly activates contralateral M1 and S1. Resistance training activates brain regions in both hemispheres, including contralateral M1, S1, SMA, and PMC, as well as ipsilateral M1, S1, SMA, and PMC. Resistance movement also activates the ipsilateral sensorimotor cortex (S1, SMA, PMC) more than active or passive movement. Active movement has higher contralateral activation in M1 compared to passive movement. Resistance and active movements increase brain activity more than passive movement. Different movements activate various cortical areas equally on both sides, but lateralization differs. The correlation between lateralization of brain regions is significant in the right cortex but not in the left cortex during three movement patterns. All types of exercise boost motor cortex excitability, but resistance exercise activates both sides of the motor cortex more extensively. The PMC is crucial for intense workouts. The right cortex shows better coordination during motor tasks than the left. fNIRS findings can help determine the length of treatment sessions.

The acute hypoalgesic effects of active head-mounted display virtual reality games.

The purpose of this study was to determine: (1) whether physically active virtual reality (VR) games exert an acute hypoaglesic effect on the thigh and bicep compared to a non-active VR game and an exercise only condition matched for exercise intensity in healthy individuals, and (2) whether movement variables during gameplay are associated with the hypoalgesic effect of the games. Twenty young adults completed five separate study sessions, with each session devoted to playing one head-mounted display VR game or stationary cycling for 15 minutes. The games included Holopoint at level 2 and level 3, Hot Squat, and Relax Walk. Pressure pain thresholds at the thigh and bicep were measured pre and post VR gameplay and cycling. Participants wore a heart rate monitor and accelerometers on the wrist and thigh during play to measure the intensity and quantity of movement. Repeated measures ANOVAs revealed that pressure pain thresholds on the bicep increased from pre to posttest for each condition. The results also revealed that pressure pain thresholds on the thigh increased only for the conditions eliciting the greatest cardiovascular response, which included Holopoint at level 3, Hot Squat, and cycling. Bivariate correlations indicated that moderate to vigorous physical activity of the thigh was associated with pain reduction at the thigh during Holopoint. These results revealed that active VR games and exercise exerted a more widespread hypoalgesic effect compared to the non-active VR game, which was likely driven in part by the intensity and quantity of movement during gameplay.

Muscle reoxygenation is slower after higher cycling intensity, and is faster and more reliable in locomotor than in accessory muscle sites.

Wearable near-infrared spectroscopy (NIRS) can be used during dynamic exercise to reflect the balance of muscle oxygen delivery and uptake. This study describes the behaviour and reliability of postexercise reoxygenation with NIRS as a function of exercise intensity at four muscle sites during an incremental cycling test. We discuss physiological components of faster and slower reoxygenation kinetics in the context of sport science and clinical applications. We hypothesised that reoxygenation would be slower at higher intensity, and that locomotor muscles would be faster than accessory muscles. We quantified test-retest reliability and agreement for each site. Twenty-one trained cyclists performed two trials of an incremental cycling protocol with 5-min work stages and 1-min rest between stages. NIRS was recorded from the locomotor vastus lateralis and rectus femoris muscles, and accessory lumbar paraspinal and lateral deltoid muscles. Reoxygenation time course was analysed as the half-recovery time (HRT) from the end of work to half of the peak reoxygenation amplitude during rest. Coefficient of variability (CV) between participants, standard error of the measurement (SEM) within participants, and intraclass correlation coefficient (ICC) for test-retest reliability were evaluated at 50%, 75%, and 100% peak workloads. A linear mixed-effects model was used to compare differences between workloads and muscle sites. HRT was slower with increasing workload in the VL, RF, and PS, but not DL. VL had the fastest reoxygenation (lowest HRT) across muscle sites at all workloads (HRT = 8, 12, 17s at 50%, 75%, 100% workload, respectively). VL also had the greatest reliability and agreement. HRT was sequentially slower between muscle sites in the order of VL < RF < PS < DL, and reliability was lower than for the VL. This study highlights the potential for using wearable NIRS on multiple muscle sites during exercise. Reoxygenation kinetics differ between local muscle sites with increasing intensity. Moderate-to-good reliability in the VL support its increasing use in sport science and clinical applications. Lower reliability in other muscle sites suggest they are not appropriate to be used alone, but may add information when combined to better reflect systemic intensity and fatigue during exercise at different intensities.

Investigating the acute effect of low and moderate intensity aerobic exercise on whole-body task learning and cognition in young adults.

Recent studies have shown that a single bout of exercise has acute improvements on various forms of memory, including procedural motor learning, through mechanisms such as the plasticity-promoting effect. This study aimed to examine (1) the acute effects of timing and intensity of aerobic exercise on the acquisition and retention of motor learning in healthy adults, (2) the effect of sleep quality of the night before and after acquisition on motor learning, and (3) the acute effects of low and moderate-intensity aerobic exercise on cognitive functions. Seventy-five healthy adults were divided into five groups: Two groups performed low or moderate intensity aerobic exercise before motor practice; two groups performed low or moderate intensity aerobic exercise after motor practice; the control group only did motor practice. Low- and moderate-intensity exercises consisted of 30 min of running at 57%-63% and 64%-76% of the maximum heart rate, respectively. Motor learning was assessed using a golf putting task. The sleep quality of the night before and after the acquisition was evaluated using the Richard Campbell Sleep Questionnaire. Cognitive function was assessed before and after aerobic exercise using the Paced Auditory Serial Acquisition Task test. Results indicated that all groups demonstrated acquisition, 1-day and 7-day retention at a similar level (p > 0.05). Regression analysis revealed no significant relationship between sleep quality on the night before the experimental day and total acquisition (p > 0.05). However, a positive correlation was found between the sleep quality on the night of the experimental day and both 1-day and 7-day retention (p < 0.05). A single bout of low or moderate acute exercise did not modify motor skill acquisition and retention. Other results showed the importance of night sleep quality on the retention and proved that a single bout of moderate intensity exercise was associated with improved cognitive function.

Exertional Rhabdomyolysis and Ultra-Trail Races: A Systematic Review Highlighting the Significant Impact of Eccentric Load

Exertional rhabdomyolysis (ER) is a condition where muscle breakdown occurs after intense and unaccustomed exercise in healthy individuals. It is characterized by muscle pain, weakness, and myoglobinuria, potentially leading to acute kidney injury and worsening the patients’ prognosis. Ultra-trail races (UT) necessitate high energy and extreme muscular exertion, which can result in significant muscle breakdown, leading to ER and elevated biomarkers such as creatine kinase (CK) and lactate dehydrogenase (LDH). These races involve longer durations and both uphill and downhill elevations, with the latter causing more muscle damage. This systematic review aims to analyse the effect of downhill elevation (at least 1000 m) in UT on muscle and liver damage biomarkers. We conducted a systematic review of four electronic databases (Pubmed, Web of Science, Scopus, and Sportdiscus) based on PRISMA guidelines for systematic reviews. We included a total of 15 articles out of 6670 published between January 2005 and March 2024. The total population sample included 348 subjects, comprising 294 men (84.48%) and 54 women (15.52%) with a mean age of 39.82 ± 6.89 years. Only one subject (0.28%) was diagnosed with ER. The median increase in CK post vs. pre was 5370.63 ± 7289.71%, LDH post vs. pre was 311.20 ± 164.4%, and liver damage biomarkers aspartate transaminase (AST) and alanine aminotransferase (ALT) obtained mean increases of 1009.94 ± 743.97% and 207.02 ± 92.84%, respectively. No liver injury cases were reported. These findings suggest that ER is often misdiagnosed in UT and may result in acute kidney injury under certain circumstances. Therefore, it is crucial to define and prepare the characteristics required for ultra runners to safely participate in these extreme races.