scholarly journals Respiratory Activity during Exercise: A Feasibility Study on Transition Point Estimation Using Impedance Pneumography

Sensors ◽  
2021 ◽  
Vol 21 (18) ◽  
pp. 6233
Author(s):  
Marcel Młyńczak ◽  
Hubert Krysztofiak

The current diagnostic procedures for assessing physiological response to exercise comprise blood lactates measurements, ergospirometry, and electrocardiography. The first is not continuous, the second requires specialized equipment distorting natural breathing, and the last is indirect. Therefore, we decided to perform the feasibility study with impedance pneumography as an alternative technique. We attempted to determine points in respiratory-related signals, acquired during stress test conditions, that suggest a transition similar to the gas exchange threshold. In addition, we analyzed whether or not respiratory activity reaches steady states during graded exercise. Forty-four students (35 females), practicing sports on different levels, performed a graded exercise test until exhaustion on cycloergometer. Eventually, the results from 34 of them were used. The data were acquired with Pneumonitor 2. The signals demonstrated that the steady state phenomenon is not as evident as for heart rate. The results indicated respiratory rate approaches show the transition point at the earliest (more than 6 min before the end of the exercise test on average), and the tidal volume ones at the latest (less than 5 min). A combination gave intermediate findings. The results showed the impedance pneumography appears reasonable for the transition point estimation, but this should be further studied with the reference.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Eugenia Murawska-Ciałowicz ◽  
Gilmara Gomes de Assis ◽  
Filipe Manuel Clemente ◽  
Yuri Feito ◽  
Petr Stastny ◽  
...  

AbstractThis study examined the effects of a nine-week intervention of four different high-intensity training modalities [high-intensity functional training (HIFT), high-intensity interval training (HIIT), high-intensity power training (HIPT), and high-intensity endurance training (HIET)] on the resting concentration of brain-derived neurotropic factor (BDNF). In addition, we evaluated the BDNF responses to Graded Exercise Test (GXT) and Wingate Anaerobic Test (WAnT) in men. Thirty-five healthy individuals with body mass index 25.55 ± 2.35 kg/m2 voluntarily participated in this study and were randomly assigned into four training groups. During nine-weeks they completed three exercise sessions per week for one-hour. BDNF was analyzed before and after a GXT and WAnT in two stages: (stage 0—before training and stage 9—after nine weeks of training). At stage 0, an increase in BDNF concentration was observed in HIFT (33%; p < 0.05), HIPT (36%; p < 0.05) and HIIT (38%; p < 0.05) after GXT. Even though HIET showed an increase in BDNF (10%) this was not statistically significant (p > 0.05). At stage 9, higher BDNF levels after GXT were seen only for the HIFT (30%; p < 0.05) and HIIT (18%; p < 0.05) groups. Reduction in BDNF levels were noted after the WAnT in stage 0 for HIFT (− 47%; p < 0.01), HIPT (− 49%; p < 0.001), HIET (− 18%; p < 0.05)], with no changes in the HIIT group (− 2%). At stage 9, BDNF was also reduced after WAnT, although these changes were lower compared to stage 0. The reduced level of BDNF was noted in the HIFT (− 28%; p < 0.05), and HIPT (− 19%;p < 0.05) groups. Additionally, all groups saw an improvement in VO2max (8%; p < 0.001), while BDNF was also correlated with lactate and minute ventilation and selected WAnT parameters. Our research has shown that resting values of BDNF after nine weeks of different forms of high-intensity training (HIT) have not changed or were reduced. Resting BDNF measured at 3th (before GXT at stage 9) and 6th day after long lasting HITs (before WAnT at stage 9) did not differed (before GXT), but in comparison to the resting value before WAnT at the baseline state, was lower in three groups. It appears that BDNF levels after one bout of exercise is depended on duration time, intensity and type of test/exercise.


2021 ◽  
Vol 28 (Supplement_1) ◽  
Author(s):  
TE Graca Rodrigues ◽  
N Cunha ◽  
P Silverio-Antonio ◽  
P Couto Pereira ◽  
B Valente Silva ◽  
...  

Abstract Funding Acknowledgements Type of funding sources: None. Introduction There is some evidence suggesting that exaggerated hypertensive response to exercise (HRE) may be associated with higher risk of future cardiovascular events, however the relationship between systolic blood pressure (SPB) during exercise test and stroke is not fully understood. Purpose To evaluate the ability to predict the risk of stroke in patients with HRE in exercise test. Methods Single-center retrospective study of consecutive patients submitted to exercise test from 2012 to 2015 with HRE to stress test. HRE was defined as a peak systolic blood pressure (PSBP) &gt; 210 mmHg in men and &gt; 190 mmHg in women, or a rise of the SBP of 60 mmHg in men or 50 mmHg in women or as a diastolic blood pressure &gt; 90 mmHg or a rise of 10 mmHg. Patient’s demographics, baseline clinical characteristics, vital signs during the stress test and the occurrence of stroke during follow-up were analysed Results We included 458 patients with HRE (76% men, 57.5 ± 10.83 years). The most frequent comorbidities were hypertension (83%), dyslipidaemia (61%), previously known coronary disease (32%), diabetes (28%) and smoking (38%). Atrial fibrillation was present in 5.9% of patients. During a mean follow-up of 60 ± 2 months, the incidence of stroke was 2.1% (n = 8), all with ischemic origin. Considering the parameters analysed on exercise test, only PSBP demonstrated to be an independent predictor of stroke (HR 1.042, CI95% 1.002-1.084, p = 0.039,) with moderate ability to predict stroke (AUC 0.735, p = 0.0016) with a most discriminatory value of 203 mmHg (sensibility 56%, specify 67%). Regarding baseline characteristics, after age, sex and comorbidities adjustment, previously controlled hypertension was found to be an independent protective factor of stroke (OR 4.247, CI 95% 0.05-0.9, p = 0.036) and atrial fibrillation was an independent predictor of stroke occurrence (HR 8.1, CI95% 1.4-46.9, p = 0.018). Atrial fibrillation was also associated with hospitalization of cardiovascular cause and major cardiovascular events occurrence (mortality, coronary syndrome and stroke). Baseline SBP was associated with atrial fibrillation development (p = 0.008). Conclusion According to our results, PSBP during exercise test is an independent predictor of stroke occurrence and should be considered as a potencial additional tool to predict stroke occurrence, particularly in high risk patients. The identification of diagnosed hypertension as a protective factor of stroke may be explained by the cardioprotective effect of antihypertensive drugs.


1982 ◽  
Vol 103 (3) ◽  
pp. 363-373 ◽  
Author(s):  
Michael L. Pollock ◽  
Carl Foster ◽  
Donald Schmidt ◽  
Charles Hellman ◽  
A.C. Linnerud ◽  
...  

2014 ◽  
Vol 46 ◽  
pp. 72
Author(s):  
Elizabeth A. Easley ◽  
W. Scott Black ◽  
Alison L. Bailey ◽  
Terry Lennie ◽  
Kelly D. Bradley ◽  
...  

Author(s):  
Christopher J. Alfiero ◽  
Samantha J. Brooks ◽  
Hannah M. Bideganeta ◽  
Coby Contreras ◽  
Ann F. Brown

The effects of a 6-week cycling high-intensity interval training (HIIT) concurrently with protein supplementation on aerobic and anaerobic fitness and body composition in collegiate dancers was investigated. Eighteen participants enrolled in a collegiate dance program were matched into three groups: high-protein (HP; 90 g·d-1), moderate-protein (MP; 40 g·d-1), and control (C; 0 g·d-1). All participants performed a 6-week HIIT intervention. Participants completed a graded exercise test, Wingate anaerobic test (Wingate), and dual energy x-ray absorptiometry scan before and after the intervention. Peak heart rate (HRpeak), peak oxygen uptake (VOpeak), peak power output (PPO), lactate threshold (LT), and ventilatory thresholds 1 (VT1) and 2 (VT2) were assessed during the graded exercise test. Peak power output, mean power output (MPO), and fatigue index (FI) were assessed during the Wingate. Lean mass (LM), fat mass (FM), visceral adipose tissue, appendicular skeletal muscle mass, and appendicular skeletal muscle mass index were assessed during dual energy x-ray absorptiometry. Body composition index (BCI) was calculated from pre and post LM and FM. Habitual diet was recorded weekly. Significance was set at p ≤ 0.05. No significant differences in VO2peak and percent fat mass (%FM) were observed between groups prior to the intervention. Significant main effects for time were observed for HRpeak (p = 0.02), VO2peak (p < 0.001), PPO (p < 0.01), LT (p < 0.001), VT1 (p < 0.001), and VT2 (p < 0.001) during the graded exercise test, and PPO (p < 0.01) and FI (p < 0.01) during the Wingate. Significant main effects for time were observed for LM (kg; p = 0.01) and FM (kg; p < 0.01). Body composition index was improved for all groups, however, no significant differences by group were observed. No significant differences were observed between groups for the measured outcomes (p > 0.05). Therefore, there was no effect of protein supplementation in the short 6-week intervention. This cycling based HIIT routine increased physical fitness, optimized aesthetics, and was a simple addition to an existing collegiate dance curriculum.


2019 ◽  
Vol 14 (4) ◽  
pp. 518-524 ◽  
Author(s):  
Mark Kramer ◽  
Mark Watson ◽  
Rosa Du Randt ◽  
Robert W. Pettitt

Purpose:To compare critical speed (CS) derived from all-out testing (AOT) for linear and shuttle running with metrics from a graded exercise test, the Yo-Yo Intermittent Recovery Test  Level 1 (YYIR1), and estimation of an 800-m-shuttle time trial.Methods:Twelve male rugby players completed a graded exercise test, the YYIR1, a linear AOT, shuttle AOTs of 25 and 50 m, and an 800-m-shuttle time trial consisting of 32 × 25-m shuttles.Results:Strong linear correlations were observed between maximum oxygen uptake () and CS (m·s−1) derived from the linear AOT (3.68 [0.62],r = .90,P < .01) and 50-m-shuttle AOT (3.19 [0.26],r = .83,P < .01). Conversely,showed lower correlations with speeds evoking CS from 25-m AOT (2.86 [0.18],r = .42,P = .18) and YYIR1 (4.36 [0.11],r = .55,P = .07). The 800-m time trial (213.58 [15.84] s) was best predicted using parameters from the 25-m AOT (r = .93, SEE = 6.60 s,P < .001).Conclusions:The AOT is a valuable method of assessing performance-specific fitness, with CS from linear and 50-m-shuttle AOTs being strong predictors of, rivaling metrics from the graded exercise test. The YYIR1 offered limited utility compared with the AOT method.


2021 ◽  
Vol 5 ◽  
pp. 205970022110448
Author(s):  
Alessandra Ventura ◽  
Fausto Romano ◽  
Mario Bizzini ◽  
Antonella Palla ◽  
Nina Feddermann

Objective Dysfunction of the autonomic cardiovascular system after a concussion is known to cause exercise intolerance due to symptoms exacerbation. The aim of this study was to compare athletes with symptoms of a sport-related concussion and healthy controls with regard to their heart rate during a graded exercise test and their heart rate recovery during the 5 min cool-down after the graded exercise test. Methods Sport-related concussion patients ( N = 61; 31% female) and controls ( N = 16; 50% female) participated in a graded exercise test on a cycle ergometer followed by 5 min active cool-down. Based on the results of graded exercise tests they were divided into four groups: (1) patients who reached the symptom threshold and had to stop the graded exercise test (symptom threshold; N = 39; 33.3% female), (2) patients with symptoms who finished the graded exercise test (S; N = 16; 25% female), (3) patients without symptoms (NS; N = 6; 33.3% female), (4) controls ( N = 16; 50% female). Main outcome measures Heart rate, severity of headache and dizziness during graded exercise test, heart rate recovery (median (heart rate recoveries/maximal heart rate) ± median absolute deviation (MAD)) 30, 60 and 300 s after the start of cool-down. Results Heart rate recovery at 30 s was significantly slower in symptom (0.95 ± 0.01) compared to all other groups ( p < 0.002; symptom threshold: 0.92 ± 0.02, NS: 0.91 ± 0.02, controls: 0.93 ± 0.02). Heart rate recovery at 60 s was significantly slower in symptom (0.90 ± 0.02) compared to the symptom threshold and controls ( p < 0.041; 0.86 ± 0.03, 0.85 ± 0.04). Heart rate recovery at 300 s was significantly slower in symptom threshold (0.72 ± 0.05) compared to controls ( p = 0.003; 0.66 ± 0.02). Conclusions Heart rate measurements in athletes with symptoms of sport-related concussion should be continued during cool-down after the graded exercise test, as dysfunction of the autonomic cardiovascular system might manifest also during cool-down.


2021 ◽  
Author(s):  
Hoi Lam Ng ◽  
Johannes Trefz ◽  
Martin Schönfelder ◽  
Henning Wackerhage

Abstract Background: Face masks are an effective, non-pharmacological strategy to reduce the transmission of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) and other pathogens. However, it is a challenge to keep masks sealed during exercise, as ventilation can increase from 5-10 L/min at rest to up to 200 L/min so that masks may be blown away from the face. To reduce leakage e.g. during exercise, a face mask was developed that is taped onto the face. The aim of this study was to investigate during a graded cycle ergometry test the effect of a taped mask on the perception of breathlessness, heart rate, lactate, and oxygen saturation when compared to a surgical mask and no mask.Methods: Four trained and healthy males and females each (n=8 in total) performed incremental cycle ergometer tests until voluntary exhaustion under three conditions: (1) No mask/control, (2) surgical mask or (3) taped mask. During these tests, we measured perception of breathlessness, heart rate, the concentration of blood lactate and peripheral oxygen saturation and analysed the resultant data with one or two-way repeated measures ANOVAs. We also used a questionnaire to evaluate mask comfort and analysed the data with paired t-tests. Results: When compared to wearing no mask, a taped face mask significantly reduces the maximal workload in a graded exercise test by 12±6% (p=0.001). Moreover, with a taped face mask, subjects perceive severe breathlessness at 12±9% lower workload (p=0.012) and oxygen saturation at 65% of the maximal workload is 1.5% lower (p=0.018) when compared to wearing no mask. Heart rate and the concentration of lactate were not significantly different at any workload. When compared to wearing a surgical mask, wearing a taped face mask has a significantly better wearing comfort (p=0.038), feels better on the skin (p=0.004), there is a lower sensation of moisture (p=0.026) and wearers perceive that less heat is generated (p=0.021). We found no sex/gender differences for any parameters. Conclusions: A taped mask is well tolerated during light and moderate exercise intensity but reduces maximal exercise capacity.


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