scholarly journals Determination of ventilatory threshold based on rating of perceived exertion scale

2004 ◽  
Vol 132 (11-12) ◽  
pp. 409-413 ◽  
Author(s):  
Stanimir Stojiljkovic ◽  
Dejan Nesic ◽  
Sanja Mazic ◽  
Dejana Popovic ◽  
Dusan Mitrovic ◽  
...  

The objective of the study was to test the possibility of using the fixed value (12-13) of the Rating of Perceived scale (RPE scale), as a valid method for determination of ventilatory threshold (VT). The sample of the subjects included 32 physically active males (age: 22.3; TV: 180.5; TM: 75.5 kg; V02max: 57.1 mL/kg/min). During the continuous test of progressively increasing load on a treadmill, cardiorespiratory and other parameters were monitored using ECG and gas analyzer. Following the test, VT and V02max were determined. During the test, at each level, at the scale from 6 to 20, the subjects pointed the number that suited best their currently feeling of strain. The RPE threshold was defined as constant value of 12-13. Average values of ventilatory and RPE threshold were expressed by parameters that were monitored and then compared by using t-test for dependent samples. No significant difference was found between mean values of VT and RPE threshold, when they were expressed by relevant parameters: speed, load, heart rate, absolute and relative oxygen consumption. Fixed value (12-13) of RPE scale may be used to detect the exercise intensity that corresponds to ventilatory threshold.


2018 ◽  
Vol 3 (4) ◽  
pp. 60 ◽  
Author(s):  
Ramires Tibana ◽  
Nuno de Sousa ◽  
Jonato Prestes ◽  
Fabrício Voltarelli

The aim of this study was to analyze blood lactate concentration (LAC), heart rate (HR), and rating perceived exertion (RPE) during and after shorter and longer duration CrossFit® sessions. Nine men (27.7 ± 3.2 years; 11.3 ± 4.6% body fat percentage and training experience: 41.1 ± 19.6 months) randomly performed two CrossFit® sessions (shorter: ~4 min and longer: 17 min) with a 7-day interval between them. The response of LAC and HR were measured pre, during, immediately after, and 10, 20, and 30 min after the sessions. RPE was measured pre and immediately after sessions. Lactate levels were higher during the recovery of the shorter session as compared with the longer session (shorter: 15.9 ± 2.2 mmol/L/min, longer: 12.6 ± 2.6 mmol/L/min; p = 0.019). There were no significant differences between protocols on HR during (shorter: 176 ± 6 bpm or 91 ± 4% HRmax, longer: 174 ± 3 bpm or 90 ± 3% HRmax, p = 0.387). The LAC was significantly higher throughout the recovery period for both training sessions as compared to pre-exercise. The RPE was increased immediately after both sessions as compared to pre-exercise, while there was no significant difference between them (shorter: 8.7 ± 0.9, longer: 9.6 ± 0.5; p = 0.360). These results demonstrated that both shorter and longer sessions induced elevated cardiovascular responses which met the recommendations for gains in cardiovascular fitness. In addition, both training sessions had a high metabolic and perceptual response, which may not be suitable if performed on consecutive days.



2015 ◽  
Vol 10 (8) ◽  
pp. 1023-1028 ◽  
Author(s):  
Vincenzo Manzi ◽  
Antonio Bovenzi ◽  
Carlo Castagna ◽  
Paola Sinibaldi Salimei ◽  
Maurizio Volterrani ◽  
...  

Purpose:To assess the distribution of exercise intensity in long-distance recreational athletes (LDRs) preparing for a marathon and to test the hypothesis that individual perception of effort could provide training responses similar to those provided by standardized training methodologies.Methods:Seven LDRs (age 36.5 ± 3.8 y) were followed during a 5-mo training period culminating with a city marathon. Heart rate at 2.0 and 4.0 mmol/L and maximal heart rate were used to establish 3 intensity training zones. Internal training load (TL) was assessed by training zones and TRIMPi methods. These were compared with the session-rating-of-perceived-exertion (RPE) method.Results:Total time spent in zone 1 was higher than in zones 2 and 3 (76.3% ± 6.4%, 17.3% ± 5.8%, and 6.3% ± 0.9%, respectively; P = .000 for both, ES = 0.98, ES = 0.99). TL quantified by session-RPE provided the same result. The comparison between session-RPE and training-zones-based methods showed no significant difference at the lowest intensity (P = .07, ES = 0.25). A significant correlation was observed between TL RPE and TL TRIMPi at both individual and group levels (r = .79, P < .001). There was a significant correlation between total time spent in zone 1 and the improvement at the running speed of 2 mmol/L (r = .88, P < .001). A negative correlation was found between running speed at 2 mmol/L and the time needed to complete the marathon (r = –.83, P < .001).Conclusions:These findings suggest that in recreational LDRs most of the training time is spent at low intensity and that this is associated with improved performances. Session-RPE is an easy-to-use training method that provides responses similar to those obtained with standardized training methodologies.



Author(s):  
Pedro L. Valenzuela ◽  
Jaime Gil-Cabrera ◽  
Eduardo Talavera ◽  
Lidia B. Alejo ◽  
Almudena Montalvo-Pérez ◽  
...  

Purpose: To compare the effectiveness of resistance power training (RPT, training with the individualized load and repetitions that maximize power output) and cycling power training (CPT, short sprint training) in professional cyclists. Methods: The participants (20 [2] y, peak oxygen uptake 78.0 [4.4] mL·kg−1·min−1) were randomly assigned to perform CPT (n = 8) or RPT (n = 10) in addition to their usual training regime for 7 weeks (2 sessions/wk). The training loads were continuously registered using the session rating of perceived exertion. The outcomes included endurance performance (8-min time trial and incremental test), as well as measures of muscle strength/power (1-repetition maximum and mean maximum propulsive power on the squat, hip thrust, and lunge exercises) and body composition (assessed by dual-energy X-ray absorptiometry). Results: No between-group differences were found for training loads or for any outcome (P > .05). Both interventions resulted in increased time-trial performance, as well as in improvements in other endurance-related outcomes (ie, ventilatory threshold, respiratory compensation point; P < .05). A significant or quasi-significant increase (P = .068 and .047 for CPT and RPT, respectively) in bone mineral content was observed after both interventions. A significant reduction in fat mass (P = .017), along with a trend (P = .059) toward a reduced body mass, was observed after RPT, but not CPT (P = .076 for the group × time interaction effect). Significant benefits (P < .05) were also observed for most strength-related outcomes after RPT, but not CPT. Conclusion: CPT and RPT are both effective strategies for the improvement of endurance performance and bone health in professional cyclists, although the latter tends to result in greater improvements in body composition and muscle strength/power.



Author(s):  
Devin Goddard McCarthy ◽  
William Bostad ◽  
Fiona Jane Powley ◽  
Jonathan P. Little ◽  
Douglas Richards ◽  
...  

There is growing interest in the effect of exogenous ketone body supplementation on exercise responses and performance. The limited studies to date have yielded equivocal data, likely due in part to differences in dosing strategy, increase in blood ketones, and participant training status. Using a randomized, double-blind, counterbalanced design, we examined the effect of ingesting a ketone monoester (KE) supplement (600 mg/kg body mass) or flavour-matched placebo in endurance-trained adults (n=10 males, n=9 females; VO2peak=57±8 ml/kg/min). Participants performed a 30-min cycling bout at ventilatory threshold intensity (71±3% VO2peak), followed 15 min later by a 3 kJ/kg body mass time-trial. KE versus placebo ingestion increased plasma [β-hydroxybutyrate] before exercise (3.9±1.0 vs 0.2±0.3 mM, p<0.0001, dz=3.4), ventilation (77±17 vs 71±15 L/min, p<0.0001, dz=1.3) and heart rate (155±11 vs 150±11 beats/min, p<0.001, dz=1.2) during exercise, and rating of perceived exertion at the end of exercise (15.4±1.6 vs 14.5±1.2, p<0.01, dz=0.85). Plasma [β-hydroxybutyrate] remained higher after KE vs placebo ingestion before the time-trial (3.5±1.0 vs 0.3±0.2 mM, p<0.0001, dz=3.1), but performance was not different (KE: 16:25±2:50 vs placebo: 16:06±2:40 min:s, p=0.20; dz=0.31). We conclude that acute ingestion of a relatively large KE bolus dose increased markers of cardiorespiratory stress during submaximal exercise in endurance-trained participants. Novelty bullets: •Limited studies have yielded equivocal data regarding exercise responses after acute ketone body supplementation. •Using a randomized, double-blind, placebo-controlled, counterbalanced design, we found that ingestion of a large bolus dose of a commercial ketone monoester supplement increased markers of cardiorespiratory stress during cycling at ventilatory threshold intensity in endurance-trained adults.



1961 ◽  
Vol 7 (2) ◽  
pp. 115-129 ◽  
Author(s):  
Samuel Natelson ◽  
Bertrum Sheid

Abstract X-ray spectroscopy was applied to the determination of the total phosphorus content of serum and the iron content of whole blood (hemoglobin). Samples were placed on confined spots on paper, dried, then passed through the X-ray field. Concentration was then determined from the peaks as drawn on a recorder. A device is described that permits automatic assay of successive samples dried on paper without delays between readings. Samples are placed in the field and rapidly withdrawn at 30-sec. intervals, the response of the recorder serving as a measure of concentration. Results for total phosphorus in serum and total iron in whole blood were compared with those obtained by a wet ashing procedure. No significant difference with respect to both mean values and precision was observed except that total iron by the wet ashing procedure was more precise. However, the X-ray technic was adequate for clinical purposes. Hemoglobin levels calculated from whole-blood iron values demonstrated that bilirubin, red cell debris, leukocytes, and lipids interfered in the colorimetric but not in the X-ray procedure. A hemoglobinometer based on the X-ray spectroscopic technic may, therefore, yield results of greater clinical significance.



1967 ◽  
Vol 13 (10) ◽  
pp. 900-908 ◽  
Author(s):  
Brigitta Mellerup

Abstract A method for the determination of serum arginase is given which combines the enzymatic formation of urea with the sensitive method of Coulombe (1) for measuring this substance. This procedure allows more accurate determinations in the normal range than do previous methods described and is convenient for clinical routine. Significant difference is found between the mean values of normal men and women, 3.9 units/L. for the former and 2.9 units/L. for the latter.



Author(s):  
E. Tavares-Silva ◽  
F. F. Donatto ◽  
R. M. V. Medeiros ◽  
S. A. Santos ◽  
A. V. Caris ◽  
...  

Abstract Background Rating of Perceived Exertion (RPE) is a subjective scale to monitor overload and fatigue during exercise. Hypoxia may worsen the perception of fatigue, compromising the self-reported perception of effort and increasing RPE. The objective was to evaluate the effects of carbohydrate (CHO) supplementation on RPE during exercise in hypoxia simulating 4200 m. Methods Eight male physically active volunteers performed two exercises at 50% VO2peak and 1% slope: exercise in hypoxia + placebo or exercise in hypoxia + CHO (6% maltodextrin) with supplementation at 20, 40, and 60 min during exercise. Oxygen Saturation (SaO2%) was assessed at baseline and after exercise, while RPE and HR were measured each 10 min during the trial. Results SaO2% decreased after exercise in both conditions of hypoxia compared to rest. The RPE did not differ between groups. However, the RPE increased in hypoxia after 20 min of exercise in relation to 10 min. The Area Under the Curve (AUC) of RPE was lower in hypoxia + CHO compared to hypoxia. The AUC of the HR/RPE ratio in the hypoxia + CHO group was higher in relation to hypoxia. Conclusions Our results indicate that CHO supplementation does not change RPE induced by 60 min of exercise at 50% VO2peak in hypoxia equivalent to 4200 m at the different times analyzed. However, in hypoxia + CHO the (AUC)-60 min of total RPE decreased during exercise, while the heart rate/RPE ratio improved, indicating lower RPE in the hypoxic environment.



2019 ◽  
Vol 14 (7) ◽  
pp. 941-948 ◽  
Author(s):  
Henrikas Paulauskas ◽  
Rasa Kreivyte ◽  
Aaron T. Scanlan ◽  
Alexandre Moreira ◽  
Laimonas Siupsinskas ◽  
...  

Purpose:To assess the weekly fluctuations in workload and differences in workload according to playing time in elite female basketball players.Methods:A total of 29 female basketball players (mean [SD] age 21 [5] y, stature 181 [7] cm, body mass 71 [7] kg, playing experience 12 [5] y) belonging to the 7 women’s basketball teams competing in the first-division Lithuanian Women’s Basketball League were recruited. Individualized training loads (TLs) and game loads (GLs) were assessed using the session rating of perceived exertion after each training session and game during the entire in-season phase (24 wk). Percentage changes in total weekly TL (weekly TL + GL), weekly TL, weekly GL, chronic workload, acute:chronic workload ratio, training monotony, and training strain were calculated. Mixed linear models were used to assess differences for each dependent variable, with playing time (low vs high) used as fixed factor and subject, week, and team as random factors.Results:The highest changes in total weekly TL, weekly TL, and acute:chronic workload ratio were evident in week 13 (47%, 120%, and 49%, respectively). Chronic workload showed weekly changes ≤10%, whereas monotony and training strain registered highest fluctuations in weeks 17 (34%) and 15 (59%), respectively. A statistically significant difference in GL was evident between players completing low and high playing times (P = .026, moderate), whereas no significant differences (P > .05) were found for all other dependent variables.Conclusions:Coaches of elite women’s basketball teams should monitor weekly changes in workload during the in-season phase to identify weeks that may predispose players to unwanted spikes and adjust player workload according to playing time.



2015 ◽  
Vol 1 (6) ◽  
pp. 270
Author(s):  
Audumbar Digambar Mali ◽  
Ritesh Bathe ◽  
Manojkumar Patil ◽  
Ashpak Tamboli

Simple, fast and reliable spectrophotometric methods were developed for determination of Levocetirizine in bulk and pharmaceutical dosage forms. The solutions of standard and the sample were prepared in methanol. The quantitative determination of the drug was carried out using the zero order derivative values measured at 230 nm and the area under the curve method values measured at 227-234 nm (n=2). Calibration graphs constructed at their wavelengths of determination were linear in the concentration range of Levocetirizine using 5-25?g/ml (r=0.998 and r=0.999) for zero order and area under the curve spectrophotometric method. All the proposed methods have been extensively validated as per ICH guidelines. There was no significant difference between the performance of the proposed methods regarding the mean values and standard deviations. Developed spectrophotometric methods in this study are simple, accurate, precise and sensitive to assay of Levocetirizine in tablets.



2016 ◽  
Vol 2 (1) ◽  
pp. 09
Author(s):  
Pandurang Tukaram Mane

Simple, fast and reliable spectrophotometric methods were developed for determination of Levocetirizine in bulk and pharmaceutical dosage forms. The solutions of standard and the sample were prepared in Methanol. The quantitative determination of the drug was carried out using the second order Derivative Area under Curve method values measured at 235-243 nm. Calibration graphs constructed at their wavelengths of determination were linear in the concentration range of Levocetirizine using 5-25?g/ml (r=0.9994) for first order Derivative Area under Curve spectrophotometric method. The proposed methods have been extensively validated as per ICH guidelines. There was no significant difference between the performance of the proposed methods regarding the mean values and standard deviations. The developed methods were successfully applied to estimate the amount of Levocetirizine in pharmaceutical formulations.



Sign in / Sign up

Export Citation Format

Share Document