scholarly journals VO2 Kinetics during Moderate Effort in Muscles of Different Masses and Training Level

2013 ◽  
Vol 2013 ◽  
pp. 1-9
Author(s):  
Omri Inbar ◽  
Marcello Faina ◽  
Sabrina Demarie ◽  
Brian J. Whipp
Keyword(s):  
Constant Load ◽  
Response Dynamics ◽  
Arm Cranking ◽  
Mean Response Time ◽  
Vo2 Kinetics ◽  
The Mean ◽  
Road Cyclists ◽  
Muscle Groups ◽  
And Training ◽  
Arm Cranking Exercise

Purpose. To examine the relative importance of central or peripheral factors in the on-transient VO2 response dynamics to exercise with “trained” and relatively “untrained” muscles. Methods. Seven professional road cyclists and seven elite kayak paddlers volunteered to participate in this study. Each completed two bouts of constant-load “square-wave” rest-to-exercise transition cycling and arm-cranking exercise at a power output 50–60% of the mode-specific VO2peak presented in a randomized order. Results. In the cyclists, the mean response time (MRT) as well as the phase II VO2 time constant () was significantly slower in the untrained compared with the trained muscles. The opposite was the case in the kayakers. With respect to the relatively untrained muscle groups, while both demonstrated faster VO2 kinetics than normal (moderately fit) subjects, the kayakers evidenced faster VO2 kinetics than the cyclists. This suggests that there is a greater stabilizing-counterforce involvement of the legs in the task of kayaking than of the arms for cycling. Conclusions. The results of the present study provide no support for the “transfer” of a training effect onto the VO2 on-transient response for moderate exercise, but rather support earlier reports demonstrating that peripheral effects may be important in dictating this kinetics.

The effects of arm cranking exercise and training on platelet aggregation in male spinal cord individuals

2004 ◽  
Vol 113 (2) ◽  
pp. 129-136 ◽  
Author(s):  
Mahmoud S El-Sayed ◽  
Ali Younesian ◽  
Khalid Rahman ◽  
Fyaz M Ismail ◽  
Zeinab El-Sayed Ali
Keyword(s):  
Spinal Cord ◽  
Platelet Aggregation ◽  
Arm Cranking ◽  
Exercise And Training ◽  
And Training ◽  
Arm Cranking Exercise

Oxygen uptake kinetics from ramp work tests: variability of single test values

1986 ◽  
Vol 61 (1) ◽  
pp. 373-376 ◽  
Author(s):  
R. L. Hughson ◽  
M. D. Inman
Keyword(s):  
Ventilatory Threshold ◽  
Oxygen Uptake Kinetics ◽  
Work Rate ◽  
Base Line ◽  
Exercise Tests ◽  
Kinetics Parameters ◽  
Mean Response Time ◽  
Vo2 Kinetics ◽  
The Mean ◽  
The Individual

The variability in the estimation of the mean response time (MRT) of O2 uptake (VO2) kinetics from single ramp work rate exercise tests was examined in six repetitions by five fit subjects. Work rate increased at 50 W/min from a base line of 25 W to a work rate of 120% ventilatory threshold. Breath-by-breath data were analyzed by linear regression from 2 min after the onset of the ramp to the 120% work rate. Individual subjects showed approximately twofold differences in estimates of MRT; the coefficient of variation from individuals ranged from 18.5 to 29.3%. The MRT obtained as the mean from the individual repetitions did not differ from the MRT obtained from pooled within-subject data. Analysis of variance on the individual MRT estimates showed 53.9% of the variability was attributable to the slope of the regression, whereas only 2.4% could be attributed to baseline VO2. It was concluded that several repetitions of the ramp work rate tests should be pooled prior to estimation of kinetics parameters.

scholarly journals Development of Perceptual Inhibition in Adolescents—a Critical Period?

Symmetry ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 457
Author(s):  
Isabel María Introzzi ◽  
María Marta Richard’s ◽  
Yesica Aydmune ◽  
Eliana Vanesa Zamora ◽  
Florencia Stelzer ◽  
...  
Keyword(s):  
Response Time ◽  
Executive Functions ◽  
Critical Period ◽  
Search Task ◽  
Probability Distributions ◽  
Linear Trajectory ◽  
Gaussian Functions ◽  
Mean Response Time ◽  
The Mean ◽  
One Year

Recent studies suggest that the developmental curves in adolescence, related to the development of executive functions, could be fitted to a non-linear trajectory of development with progressions and retrogressions. Therefore, the present study proposes to analyze the pattern of development in Perceptual Inhibition (PI), considering all stages of adolescence (early, middle, and late) in intervals of one year. To this aim, we worked with a sample of 275 participants between 10 and 25 years, who performed a joint visual and search task (to measure PI). We have fitted ex-Gaussian functions to the probability distributions of the mean response time across the sample and performed a covariance analysis (ANCOVA). The results showed that the 10- to 13-year-old groups performed similarly in the task and differ from the 14- to 19-year-old participants. We found significant differences between the older group and all the rest of the groups. We discuss the important changes that can be observed in relation to the nonlinear trajectory of development that would show the PI during adolescence.

scholarly journals Influence of Menstrual Cycle or Hormonal Contraceptive Phase on Energy Intake and Metabolic Hormones—A Pilot Study

Endocrines ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 79-90
Author(s):  
Johanna K. Ihalainen ◽  
Ida Löfberg ◽  
Anna Kotkajuuri ◽  
Heikki Kyröläinen ◽  
Anthony C. Hackney ◽  
...  
Keyword(s):  
Menstrual Cycle ◽  
Energy Intake ◽  
Hormonal Contraceptive ◽  
Group Differences ◽  
Metabolic Hormones ◽  
Recreational Athletes ◽  
Total Ghrelin ◽  
17Β Estradiol ◽  
The Mean ◽  
And Training

Sex hormones are suggested to influence energy intake (EI) and metabolic hormones. This study investigated the influence of menstrual cycle (MC) and hormonal contraceptive (HC) cycle phases on EI, energy availability (EA), and metabolic hormones in recreational athletes (eumenorrheic, NHC = 15 and monophasic HC-users, CHC = 9). In addition, 72-h dietary and training logs were collected in addition to blood samples, which were analyzed for 17β-estradiol (E2), progesterone (P4), leptin, total ghrelin, insulin, and tri-iodothyronine (T3). Measurements were completed at four time-points (phases): Bleeding, mid-follicular (FP)/active 1, ovulation (OVU)/active 2, mid-luteal (LP)/inactive in NHC/CHC, respectively. As expected, E2 and P4 fluctuated significantly in NHC (p < 0.05) and remained stable in CHC. In NHC, leptin increased significantly between bleeding and ovulation (p = 0.030) as well as between FP and OVU (p = 0.022). No group differences in other measured hormones were observed across the MC and HC cycle. The mean EI and EA were similar between phases, with no significant differences observed in macronutrient intake over either the MC or HC. While the MC phase might have a small, but statistically significant effect on leptin, the findings of the present study suggest that the MC or HC phase does not significantly alter ad libitum EI or EA in recreational athletes.

scholarly journals Arm-cranking exercise assisted by Functional Electrical Stimulation in C6 tetraplegia: A pilot study

2009 ◽  
Vol 16 (6) ◽  
pp. 415-427 ◽  
Author(s):  
S. Coupaud ◽  
H. Gollee ◽  
K.J. Hunt ◽  
M.H. Fraser ◽  
D.B. Allan ◽  
...  
Keyword(s):  
Electrical Stimulation ◽  
Pilot Study ◽  
Functional Electrical Stimulation ◽  
Arm Cranking ◽  
Arm Cranking Exercise

scholarly journals Cardiovascular Responses to Electrical Stimulation-Induced Leg Cycling Versus Voluntary Arm Cranking Exercise

2004 ◽  
Vol 36 (Supplement) ◽  
pp. S60
Author(s):  
Thomas W. Janssen ◽  
Laurien M. Buffart ◽  
Nina M.C. Mathijssen ◽  
A. Peter Hollander ◽  
Christof A.J. Smit ◽  
...  
Keyword(s):  
Electrical Stimulation ◽  
Cardiovascular Responses ◽  
Arm Cranking ◽  
Leg Cycling ◽  
Arm Cranking Exercise

Prostate and dominant intraprostatic lesion segmentation on PET/CT using cascaded regional-net

2021 ◽  
Author(s):  
Luke A Matkovic ◽  
Tonghe Wang ◽  
Yang Lei ◽  
Oladunni O Akin-Akintayo ◽  
Olayinka A Abiodun Ojo ◽  
...  
Keyword(s):  
Radiation Therapy ◽  
Cross Validation ◽  
Ct Images ◽  
Second Step ◽  
Prostate Segmentation ◽  
Positron Emission ◽  
Pet Ct ◽  
The Mean ◽  
And Training ◽  
Fold Cross Validation

Abstract Focal dose boost to dominant intraprostatic lesions (DILs) has recently been proposed for prostate radiation therapy. Accurate and fast delineation of the prostate and DILs is thus required during treatment planning. We propose a learning-based method using positron emission tomography (PET)/computed tomography (CT) images to automatically segment the prostate and its DILs. To enable end-to-end segmentation, a deep learning-based method, called cascaded regional-Net, is utilized. The first network, referred to as dual attention network (DAN), is used to segment the prostate via extracting comprehensive features from both PET and CT images. A second network, referred to as mask scoring regional convolutional neural network (MSR-CNN), is used to segment the DILs from the PET and CT within the prostate region. Scoring strategy is used to diminish the misclassification of the DILs. For DIL segmentation, the proposed cascaded regional-Net uses two steps to remove normal tissue regions, with the first step cropping images based on prostate segmentation and the second step using MSR-CNN to further locate the DILs. The binary masks of DILs and prostates of testing patients are generated from PET/CT by the trained network. To evaluate the proposed method, we retrospectively investigated 49 PET/CT datasets. On each dataset, the prostate and DILs were delineated by physicians and set as the ground truths and training targets. The proposed method was trained and evaluated using a five-fold cross-validation and a hold-out test. The mean surface distance and DSC values were 0.666±0.696mm and 0.932±0.059 for the prostate and 1.209±1.954mm and 0.757±0.241 for the DILs among all 49 patients. The proposed method has demonstrated great potential for improving the efficiency and reducing the observer variability of prostate and DIL contouring for DIL focal boost prostate radiation therapy.

Nursing Students’ Competency to Attend Disaster Situations: A Study in Western Iran

2021 ◽  
pp. 1-5
Author(s):  
Fatemeh Kaviani ◽  
Fatemeh Aliakbari ◽  
Hojjat Sheikhbardsiri ◽  
Paul Arbon
Keyword(s):  
Nursing Education ◽  
Nursing Students ◽  
Disaster Preparedness ◽  
Health Care Team ◽  
Competency Assessment ◽  
Western Iran ◽  
Undergraduate Nursing ◽  
History Of ◽  
The Mean ◽  
And Training

Abstract Objective: The disaster preparedness of nurses is important as nurses are members of a health care team that needs to work systematically and collaboratively in all conditions. Although education and training naturally underpin effective practice, disaster nursing education is rarely provided to nurses in Iran. Because disaster situations, by definition, overwhelm health services, it is likely that nursing students will be required to join their colleagues in the response. The purpose of this study was to evaluate the competency of nursing students to attend disaster situations. Methods: This descriptive, analytical study was conducted in western Iran in 2020. A total of 70 nursing students in the fourth (final) year of their undergraduate nursing education entered the study by a census sampling method. Data collection was undertaken using a validated disaster competency assessment questionnaire. The data were analyzed using SPSS version 21 (IBM Corp, Armonk, NY) with descriptive and analytic tests. Results: The mean age of participants was 21.4 ± 2.14 and 57.1% of them were women; 45 participants (64.3%) had received no disaster-related training, and 88.6% had no history of participating in disaster exercises. The total score for nursing students’ competence was 125.58 ± 14.19. There was a significant relationship between the mean score of nursing competence in response to disasters and student history of participating in an exercise and training course (P < 0.001). Conclusion: Students’ competence in disaster situations is poor. Awareness of the competence condition of nurses is the first step to improve their preparedness as the most key members of the disaster health team. Conducting disaster-related training may be appropriate. The results of this study can provide evidence for the development of educational policies in disaster nursing education.

Study of Industrial Model for Five-Input, Five-Stage Queueing Network

2016 ◽  
pp. 300-339
Author(s):  
Jitendra Kumar ◽  
Vikas Shinde
Keyword(s):  
Response Time ◽  
Textile Industry ◽  
Optimal Path ◽  
Queueing Network ◽  
Numerical Illustration ◽  
Mean Response Time ◽  
Final Destination ◽  
Optimal Capacity ◽  
Mean Waiting Time ◽  
The Mean

In this paper, we have developed an industrial model for textile industry with five-input, five-stage queueing network, wherein system receives orders from clients that are waiting to be served. The aim of this paper is to compute the optimal path that will provide the least response time for delivery of items to the final destination, through the five stages under queueing network. The mean number of items that can be delivered is minimum response time constitute the optimal capacity of the network. The last node in each stage of the network can be executed in the least possible response time. Various performance indices were carried out such as mean number of item in the system, mean number of item in queue, mean response time, mean waiting time. We have established the equivalent queueing network to analyze the various performance measures with numerical illustration and graph.

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