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Journal of Sport and Health Science Jul 2024Near-infrared spectroscopy (NIRS) technology has allowed for the measurement of cerebral and skeletal muscle oxygenation simultaneously during exercise. Since this... (Review)
Review
BACKGROUND
Near-infrared spectroscopy (NIRS) technology has allowed for the measurement of cerebral and skeletal muscle oxygenation simultaneously during exercise. Since this technology has been growing and is now successfully used in laboratory and sports settings, this systematic review aimed to synthesize the evidence and enhance an integrative understanding of blood flow adjustments and oxygen (O) changes (i.e., the balance between O delivery and O consumption) within the cerebral and muscle systems during exercise.
METHODS
A systematic review was conducted using PubMed, Embase, Scopus, and Web of Science databases to search for relevant studies that simultaneously investigated cerebral and muscle hemodynamic changes using the near-infrared spectroscopy system during exercise. This review considered manuscripts written in English and available before February 9, 2023. Each step of screening involved evaluation by 2 independent authors, with disagreements resolved by a third author. The Joanna Briggs Institute Critical Appraisal Checklist was used to assess the methodological quality of the studies.
RESULTS
Twenty studies were included, of which 80% had good methodological quality, and involved 290 young or middle-aged adults. Different types of exercises were used to assess cerebral and muscle hemodynamic changes, such as cycling (n = 11), treadmill (n = 1), knee extension (n = 5), isometric contraction of biceps brachii (n = 3), and duet swim routines (n = 1). The cerebral hemodynamics analysis was focused on the frontal cortex (n = 20), while in the muscle, the analysis involved vastus lateralis (n = 18), gastrocnemius (n = 3), biceps brachii (n = 5), deltoid (n = 1), and intercostal muscle (n = 1). Overall, muscle deoxygenation increases during exercise, reaching a plateau in voluntary exhaustion, while in the brain, oxyhemoglobin concentration increases with exercise intensity, reaching a plateau or declining at the exhaustion point.
CONCLUSION
Muscle and cerebral oxygenation respond differently to exercise, with muscle increasing O utilization and cerebral tissue increasing O delivery during exercise. However, at the exhaustion point, both muscle and cerebral oxygenation become compromised. This is characterized by a reduction in blood flow and a decrease in O extraction in the muscle, while in the brain, oxygenation reaches a plateau or decline, potentially resulting in motor failure during exercise.
Topics: Humans; Muscle, Skeletal; Oxygen Consumption; Spectroscopy, Near-Infrared; Exercise; Brain; Hemodynamics; Oxygen; Cerebrovascular Circulation; Adult
PubMed: 38462172
DOI: 10.1016/j.jshs.2024.03.003 -
Sports Medicine (Auckland, N.Z.) May 2024Running biomechanics is considered an important determinant of running economy (RE). However, studies examining associations between running biomechanics and RE report... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Running biomechanics is considered an important determinant of running economy (RE). However, studies examining associations between running biomechanics and RE report inconsistent findings.
OBJECTIVE
The aim of this systematic review was to determine associations between running biomechanics and RE and explore potential causes of inconsistency.
METHODS
Three databases were searched and monitored up to April 2023. Observational studies were included if they (i) examined associations between running biomechanics and RE, or (ii) compared running biomechanics between groups differing in RE, or (iii) compared RE between groups differing in running biomechanics during level, constant-speed, and submaximal running in healthy humans (18-65 years). Risk of bias was assessed using a modified tool for observational studies and considered in the results interpretation using GRADE. Meta-analyses were performed when two or more studies reported on the same outcome. Meta-regressions were used to explore heterogeneity with speed, coefficient of variation of height, mass, and age as continuous outcomes, and standardization of running shoes, oxygen versus energetic cost, and correction for resting oxygen or energy cost as categorical outcomes.
RESULTS
Fifty-one studies (n = 1115 participants) were included. Most spatiotemporal outcomes showed trivial and non-significant associations with RE: contact time r = - 0.02 (95% confidence interval [CI] - 0.15 to 0.12); flight time r = 0.11 (- 0.09 to 0.32); stride time r = 0.01 (- 0.8 to 0.50); duty factor r = - 0.06 (- 0.18 to 0.06); stride length r = 0.12 (- 0.15 to 0.38), and swing time r = 0.12 (- 0.13 to 0.36). A higher cadence showed a small significant association with a lower oxygen/energy cost (r = - 0.20 [- 0.35 to - 0.05]). A smaller vertical displacement and higher vertical and leg stiffness showed significant moderate associations with lower oxygen/energy cost (r = 0.35, - 0.31, - 0.28, respectively). Ankle, knee, and hip angles at initial contact, midstance or toe-off as well as their range of motion, peak vertical ground reaction force, mechanical work variables, and electromyographic activation were not significantly associated with RE, although potentially relevant trends were observed for some outcomes.
CONCLUSIONS
Running biomechanics can explain 4-12% of the between-individual variation in RE when considered in isolation, with this magnitude potentially increasing when combining different variables. Implications for athletes, coaches, wearable technology, and researchers are discussed in the review.
PROTOCOL REGISTRATION
https://doi.org/10.17605/OSF.IO/293 ND (OpenScience Framework).
Topics: Humans; Running; Biomechanical Phenomena; Observational Studies as Topic; Energy Metabolism; Oxygen Consumption
PubMed: 38446400
DOI: 10.1007/s40279-024-01997-3 -
Bioengineering & Translational Medicine Mar 2024The aim of assisted reproductive technology (ART) is to select the high-quality sperm, oocytes, and embryos, and finally achieve a successful pregnancy. However,... (Review)
Review
The aim of assisted reproductive technology (ART) is to select the high-quality sperm, oocytes, and embryos, and finally achieve a successful pregnancy. However, functional evaluation is hindered by intra- and inter-operator variability. Microfluidic chips emerge as the one of the most powerful tools to analyze biological samples for reduced size, precise control, and flexible extension. Herein, a systematic search was conducted in PubMed, Scopus, Web of Science, ScienceDirect, and IEEE Xplore databases until March 2023. We displayed and prospected all detection strategies based on microfluidics in the ART field. After full-text screening, 71 studies were identified as eligible for inclusion. The percentages of human and mouse studies equaled with 31.5%. The prominent country in terms of publication number was the USA ( = 13). Polydimethylsiloxane ( = 49) and soft lithography ( = 28) were the most commonly used material and fabrication method, respectively. All articles were classified into three types: sperm ( = 38), oocytes ( = 20), and embryos ( = 13). The assessment contents included motility, counting, mechanics, permeability, impedance, secretion, oxygen consumption, and metabolism. Collectively, the microfluidic chip technology facilitates more efficient, accurate, and objective evaluation in ART. It can even be combined with artificial intelligence to assist the daily activities of embryologists. More well-designed clinical studies and affordable integrated microfluidic chips are needed to validate the safety, efficacy, and reproducibility. Trial registration: The protocol was registered in the Open Science Frame REGISTRIES (identification: osf.io/6rv4a).
PubMed: 38435817
DOI: 10.1002/btm2.10625 -
Mayo Clinic Proceedings. Innovations,... Apr 2024To provide a synthesis of randomized controlled trials (RCTs) investigating statin-associated muscle symptoms (SAMS) in adults who underwent exercise training...
OBJECTIVE
To provide a synthesis of randomized controlled trials (RCTs) investigating statin-associated muscle symptoms (SAMS) in adults who underwent exercise training intervention.
PATIENTS AND METHODS
We systematically searched 5 electronic databases for placebo-controlled RCTs through January 31, 2023. We included short-term and long-term exercise interventions that compared the efficacy and safety of exercise+statin vs exercise+placebo in healthy adults and reported SAMS preintervention and postintervention. Publication bias and methodological study quality assessments were performed.
RESULTS
Five of 454 potentially qualifying RCTs met the inclusion criteria, all short-term exercise RCTs. Participants were predominantly physically inactive young to middle-aged (M=37.2 y) men (57%), 252 (49%) who were on statin therapy, and 271 (53%) on placebo. Of the 3 RCTs providing qualitative SAMS results, 19 (9%) out of 220 participants reported SAMS on exercise+statin and 10 (4%) out of 234 reported SAMS on exercise+placebo. There was no difference between exercise+statin vs exercise+placebo for maximal oxygen consumption (=-0.18; 95% CI, -0.37 to 0.00; =.06) or creatine kinase after short-term exercise (=0.59; 95% CI, -0.06 to 1.25; =.08). Participants in the exercise+statin group reduced low-density lipoprotein cholesterol vs exercise+placebo (=-1.84; 95% CI, -2.28 to -1.39; <.001). Most of the RCTs exhibited low levels of risk of bias (=4, 80%) and achieved moderate methodological study quality (75.0%±5.2%).
CONCLUSION
Self-reported SAMs tended to be 5% greater after short-term exercise in statin users compared with placebo, although this difference did not achieve statistical significance. There remains an important need for placebo-controlled RCTs investigating the prevalence of statin-induced SAMS during exercise training.
PubMed: 38384718
DOI: 10.1016/j.mayocpiqo.2024.01.003 -
The Journal of Experimental Biology Mar 2024From bacteria to metazoans, higher density populations have lower per capita metabolic rates than lower density populations. The negative covariance between population...
From bacteria to metazoans, higher density populations have lower per capita metabolic rates than lower density populations. The negative covariance between population density and metabolic rate is thought to represent a form of adaptive metabolic plasticity. A relationship between density and metabolism was actually first noted 100 years ago, and was focused on spermatozoa; even then, it was postulated that adaptive plasticity drove this pattern. Since then, contemporary studies of sperm metabolism specifically assume that sperm concentration has no effect on metabolism and that sperm metabolic rates show no adaptive plasticity. We did a systematic review to estimate the relationship between sperm aerobic metabolism and sperm concentration, for 198 estimates spanning 49 species, from protostomes to humans from 88 studies. We found strong evidence that per capita metabolic rates are concentration dependent: both within and among species, sperm have lower metabolisms in dense ejaculates, but increase their metabolism when diluted. On average, a 10-fold decrease in sperm concentration increased per capita metabolic rate by 35%. Metabolic plasticity in sperm appears to be an adaptive response, whereby sperm maximize their chances of encountering eggs.
Topics: Humans; Male; Semen; Sperm Motility; Spermatozoa; Energy Metabolism
PubMed: 38380562
DOI: 10.1242/jeb.246674 -
Transplantation Reviews (Orlando, Fla.) Apr 2024Frailty, malnutrition and sarcopenia lead to a significant increase in morbidity and mortality before and after liver transplantation (LT). Prehabilitation attempts to... (Review)
Review
BACKGROUND
Frailty, malnutrition and sarcopenia lead to a significant increase in morbidity and mortality before and after liver transplantation (LT). Prehabilitation attempts to optimize physical fitness of individuals before major surgeries. To date, little is known about its impact on patients awaiting LT.
AIMS
The aim of our scoping review was to describe whether prehabilitation in patients awaiting LT is feasible and safe, and whether it leads to a change in clinical parameters before or after transplantation.
METHODS
We performed a systematic review of the literature from 1946 to November 2023 to identify prospective studies and randomized controlled trials of adult LT candidates who participated in an exercise training program.
RESULTS
Out of 3262 citations initially identified, six studies were included. Studies were heterogeneous in design, patient selection, intervention, duration, and outcomes assessed. All studies were self-described as pilot or feasibility studies and had a sample size ranging from 13 to 33. Two studies were randomized controlled trials. Two study restricted to patients with cirrhosis who were eligible for liver transplantation or on the transplant list. Exercise programs lasted between 6 and 12 weeks. In terms of feasibility, proportion of eligible patients that were recruited was between 54 and 100%. Program completion ranged between 38 and 90%. Interventions appeared safe with 9 (9.2%) adverse events noted. In the intervention group, improvements were generally noted in peak oxygen consumption and workload, 6-min walking distance, and muscle strength. One study suggested a decrease in post-transplant hospital length of stay.
CONCLUSIONS
Overall, it appears that prehabilitation with exercise training is feasible, and safe in patients awaiting LT. Higher quality and larger studies are needed to confirm its impact on pre- and post-transplantation-related outcomes.
Topics: Adult; Humans; Liver Transplantation; Preoperative Exercise; Prospective Studies; Exercise; Exercise Therapy; Quality of Life; Preoperative Care; Postoperative Complications
PubMed: 38367398
DOI: 10.1016/j.trre.2024.100835 -
Sports Medicine (Auckland, N.Z.) Apr 2024In the last 5 years since our last systematic review, a significant number of articles have been published on the technical aspects of muscle near-infrared spectroscopy...
BACKGROUND
In the last 5 years since our last systematic review, a significant number of articles have been published on the technical aspects of muscle near-infrared spectroscopy (NIRS), the interpretation of the signals and the benefits of using the NIRS technique to measure the physiological status of muscles and to determine the workload of working muscles.
OBJECTIVES
Considering the consistent number of studies on the application of muscle oximetry in sports science published over the last 5 years, the objectives of this updated systematic review were to highlight the applications of muscle oximetry in the assessment of skeletal muscle oxidative performance in sports activities and to emphasize how this technology has been applied to exercise and training over the last 5 years. In addition, some recent instrumental developments will be briefly summarized.
METHODS
Preferred Reporting Items for Systematic Reviews guidelines were followed in a systematic fashion to search, appraise and synthesize existing literature on this topic. Electronic databases such as Scopus, MEDLINE/PubMed and SPORTDiscus were searched from March 2017 up to March 2023. Potential inclusions were screened against eligibility criteria relating to recreationally trained to elite athletes, with or without training programmes, who must have assessed physiological variables monitored by commercial oximeters or NIRS instrumentation.
RESULTS
Of the identified records, 191 studies regrouping 3435 participants, met the eligibility criteria. This systematic review highlighted a number of key findings in 37 domains of sport activities. Overall, NIRS information can be used as a meaningful marker of skeletal muscle oxidative capacity and can become one of the primary monitoring tools in practice in conjunction with, or in comparison with, heart rate or mechanical power indices in diverse exercise contexts and across different types of training and interventions.
CONCLUSIONS
Although the feasibility and success of the use of muscle oximetry in sports science is well documented, there is still a need for further instrumental development to overcome current instrumental limitations. Longitudinal studies are urgently needed to strengthen the benefits of using muscle oximetry in sports science.
Topics: Humans; Oximetry; Muscle, Skeletal; Spectroscopy, Near-Infrared; Oxygen Consumption; Sports Medicine
PubMed: 38345731
DOI: 10.1007/s40279-023-01987-x -
Hellenic Journal of Cardiology : HJC =... 2024This systematic review and meta-analysis aims to explore in heart failure (HF) patients with reduced ejection fraction (EF) undergoing exercise-based cardiac... (Meta-Analysis)
Meta-Analysis
Ergophysiological evaluation of heart failure patients with reduced ejection fraction undergoing exercise-based cardiac rehabilitation: A systematic review and meta-analysis.
BACKGROUND
This systematic review and meta-analysis aims to explore in heart failure (HF) patients with reduced ejection fraction (EF) undergoing exercise-based cardiac rehabilitation the following: 1) the comparison of temporal changes between peak oxygen uptake (VO2peak) and first ventilatory threshold (VO2VT1), 2) the association of VO2peak and VO2VT1 changes with physiological factors, and 3) the differential effects of continuous aerobic exercise (CAE) and interval training (IT) on VO2peak and VO2VT1.
METHODS
A systematic literature search was conducted in PubMed, CENTRAL, and Scopus. Inclusion criteria were 1) original research articles using exercise-based cardiac rehabilitation, 2) stable HF patients with reduced EF, 3) available values of VO2peak and VO2VT1 (in mL/kg/min) both at baseline and after exercise training with comparison between these time points.
RESULTS
Among the 30 eligible trials, 24 used CAE, 5 IT, and one CAE and IT. Multivariable meta-regression with duration of exercise training and percentage of males as independent variables and the change in VO2peak as a dependent variable showed that the change in VO2peak was negatively associated with duration of exercise training (coefficient=-0.061, p=0.027), implying the possible existence of a waning effect of exercise training on VO2peak in the long term. Multivariable meta-regression demonstrated that both age (coefficient=-0.140, p<0.001) and EF (coefficient=-0.149, p<0.001) could predict the change in VO2VT1, whereas only age (coefficient=-0.095, p=0.022), but not EF (coefficient = 0.082, p = 0.100), could predict the change in VO2peak. The posttraining peak respiratory exchange ratio, as an index of maximum effort during exercise testing, correlated positively with the change in VO2peak (coefficient=-0.021, p=0.044). The exercise-induced changes of VO2peak (p = 0.438) and VO2VT1 (p = 0.474) did not differ between CAE and IT groups.
CONCLUSIONS
Improvement of endurance capacity during cardiac rehabilitation may be detected more accurately with the assessment of VO2VT1 rather than VO2peak.
Topics: Female; Humans; Male; Cardiac Rehabilitation; Exercise Test; Exercise Therapy; Exercise Tolerance; Heart Failure; Oxygen Consumption; Stroke Volume
PubMed: 38246276
DOI: 10.1016/j.hjc.2024.01.004 -
BMC Musculoskeletal Disorders Jan 2024Gait disorders and as a consequence, robotic rehabilitation techniques are becoming increasingly prevalent as the population ages. In the area of rehabilitation... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Gait disorders and as a consequence, robotic rehabilitation techniques are becoming increasingly prevalent as the population ages. In the area of rehabilitation robotics, using lightweight single hip joint exoskeletons are of significance. Considering no prior systematic review article on clinical outcomes, we aim to systematically review powered hip exoskeletons in terms of gait parameters and metabolic expenditure effects.
METHODS
Three databases of PubMed, Scopus, and Web of science were searched for clinical articles comparing outcomes of gait rehabilitation using hip motorized exoskeleton with conventional methods, on patients with gait disorder or healthy individuals. Of total number of 37 reviewed articles, 14 trials were quantitatively analyzed. Analyses performed in terms of gait spatiotemporal parameters like speed (self-speed and maximum speed), step length, stride length, cadence, and oxygen consumption.
RESULTS
Improved clinical outcomes of gait spatiotemporal parameters with hip joint exoskeletons are what our review's findings show. In terms of gait values, meta-analysis indicates that rehabilitation with single hip joint exoskeleton enhanced parameters of maximum speed by 0.13 m/s (0.10-0.17) and step length by 0.06 m (0.05-0.07). For the remaining investigated gait parameters, no statistically significant difference was observed. Regarding metabolic parameters, oxygen consumption was lower in individuals treated with hip exoskeleton (- 1.23 ml/min/kg; range - 2.13 to - 0.32).
CONCLUSION
Although the analysis demonstrated improvement with just specific gait measures utilizing powered hip exoskeletons, the lack of improvement in all parameters is likely caused by the high patient condition heterogeneity among the evaluated articles. We also noted in patients who rehabilitated with the hip exoskeleton, the oxygen cost was lower. More randomized controlled trials are needed to verify both the short- and long-term clinical outcomes, including patient-reported measures.
LEVEL OF EVIDENCE
Level I (systematic review and meta-analysis).
Topics: Humans; Exoskeleton Device; Gait; Hip Joint; Robotics; Walking
PubMed: 38245729
DOI: 10.1186/s12891-024-07189-4 -
Sports Medicine (Auckland, N.Z.) Apr 2024Cardiorespiratory fitness (CRF) is an important indicator of current and future health. While the impact of habitual physical activity on CRF is well established, the... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Cardiorespiratory fitness (CRF) is an important indicator of current and future health. While the impact of habitual physical activity on CRF is well established, the role of sedentary behaviour (SB) remains less understood.
OBJECTIVE
We aimed to determine the effect of SB on CRF.
METHODS
Searches were conducted in MEDLINE, Embase, PsycINFO, CINAHL and SPORTDiscus from inception to August 2022. Randomised controlled trials, quasi-experimental studies and cohort studies that assessed the relationship between SB and CRF were eligible. Narrative syntheses and meta-analyses summarised the evidence, and Grading of Recommendations, Assessment, Development and Evaluation (GRADE) certainty was based on evidence from randomised controlled trials.
RESULTS
This review included 18 studies that focused on youth (four randomised controlled trials, three quasi-experimental studies, 11 cohort studies) and 24 on adult populations (15 randomised controlled trials, five quasi-experimental studies, four cohort studies). In youth and adults, evidence from randomised controlled trials suggests mixed effects of SB on CRF, but with the potential for interventions to improve CRF. Quasi-experimental and cohort studies also support similar conclusions. Certainty of evidence was very low for both age groups. A meta-analysis of adult randomised controlled trials found that interventions targeting reducing SB, or increasing physical activity and reducing SB, had a significant effect on post-peak oxygen consumption (mean difference = 3.16 mLkgmin, 95% confidence interval: 1.76, 4.57).
CONCLUSIONS
Evidence from randomised controlled trials indicates mixed associations between SB and CRF, with the potential for SB to influence CRF, as supported by meta-analytical findings. Further well-designed trials are warranted to confirm the relationship between SB and CRF, explore the effects of SB independent from higher intensity activity, and investigate the existence of such relationships in paediatric populations.
CLINICAL TRIAL REGISTRATION
PROSPERO CRD42022356218.
Topics: Humans; Cardiorespiratory Fitness; Sedentary Behavior; Exercise; Adult; Randomized Controlled Trials as Topic
PubMed: 38225444
DOI: 10.1007/s40279-023-01986-y