The Effects of Caffeine in Women during Aerobic-Dance Bench Stepping

Author(s):  
Jennifer N. Ahrens ◽  
Lisa K. Lloyd ◽  
Sylvia H. Crixell ◽  
John L. Walker

People of all ages and fitness levels participate regularly in aerobic-dance bench stepping (ADBS) to increase fitness and control body weight. Any reasonable method for enhancing the experience or effectiveness of ADBS would be beneficial. This study examined the acute effects of a single dose of caffeine on physiological responses during ADBS in women. When compared with a placebo, neither a 3- nor a 6-mg/kg dose of caffeine altered physiological responses or rating of perceived exertion (RPE) in 20 women (age 19–28 y) of average fitness level, not habituated to caffeine, while they performed an ADBS routine. Since neither dose of caffeine had any effect on VO2, Vco2, minute ventilation, respiratory-exchange ratio, rate of energy expenditure, heart rate, or RPE during ADBS exercise, it would not be prudent for a group exercise leader to recommend caffeine to increase energy cost or decrease perception of effort in an ADBS session. Furthermore, caffeine ingestion should not interfere with monitoring intensity using heart rate or RPE during ADBS.

Author(s):  
Atef M. Ghaleb ◽  
Mohamed Z. Ramadan ◽  
Ahmed Badwelan ◽  
Khalid Saad Aljaloud

Objective: The purpose of this study was to evaluate the lifting capabilities of individuals in hypoxia when they wear different types of safety shoes and to investigate the behavior of the physiological responses induced by the lifting process associated with those variables. Methods: An experimental design was used, based on two sessions. The first was training and acclimatization session, then an experimental lifting phase. A total of ten male students of King Saud University were recruited in the study. A four-way repeated measures design, with four independent variables and six dependent variables, was used in this research. The independent variables that were studied in the experimental lifting phase were: ambient oxygen content (15%, 18%, and 21%), safety shoes type (light-duty, medium-duty, and heavy-duty), lifting frequency (1 and 4 lifts/min), and replication (first and second trials). The dependent variables were also: maximum acceptable weights lifting using the psychophysical technique, heart rate (HR), electromyography (EMG) of (biceps brachii, trapezius, anterior deltoid, and erector spinae), safety shoes discomfort rating, rating of perceived exertion, and ambient oxygen discomfort rating. Results: The maximum acceptable weights lifting that were selected by participants at lower levels of the independent variables (ambient oxygen content 21%, lifting frequency 1 lift/min, and first replication) were significantly higher than at high levels of the independent variables (ambient oxygen content 15%, lifting frequency 4 lift/min, and second replication). Several interaction effects were also significant. Conclusions: It provides evidence that the ambient oxygen content increases the intensity of workload in lifting tasks. It showed that oxygen content affects the psychophysical selection of maximum acceptable weights lifting and the physiological responses represented in muscular activities and heart rate. It suggests that ambient oxygen content must be considered along with the type of safety shoes worn when the lifting task at altitudes occurs.


Author(s):  
Kirstie J Turner ◽  
Anthony J Rice

Stationary cycling is a common training mode of rowers, used to provide variety in training programs and prevent overuse injuries commonly associated with the repetitive nature of the rowing stroke. The purpose of this study was to investigate the differences in physiological responses on a Concept II BikeErg (Concept II BikeErg; Concept2 Inc., US) and Concept II RowErg (Concept II Model D; Concept2 Inc., US) at matched submaximal workloads so training load can be appropriately prescribed for stationary cycling. Ten well-trained, male rowers completed 6 min of exercise at four submaximal workloads (50%, 62.5%, 75% and 87.5% of their most recent 2000 m RowErg score) interspersed with 2-minute recovery periods on both ergometers in a single day. Ergometer order was randomised and balanced between groups. At matched power output (PO) results while on the RowErg were significantly higher across all workloads for rate of oxygen consumption ([Formula: see text]), rate of carbon dioxide production ([Formula: see text]), minute ventilation ([Formula: see text]) and heart rate (HR) (p < 0.05) and across the final two workloads for Rating of Perceived Exertion (RPE) and blood lactate concentration (BLa) (p < 0.05). When oxygen uptake at a fixed value ([Formula: see text] = 3.5 L.min−1) was matched between groups results while on the RowErg were significantly lower for PO, BLa, [Formula: see text], RER and RPE whereas [Formula: see text] and HR were similar to the BikeErg. These results support the understanding that displayed power output on the RowErg does not account for all work done during the rowing stroke cycle, specifically during the recovery phase. In conclusion, the physiological responses on the Concept II BikeErg are no more closely aligned to the Concept II RowErg than previously shown for similar cycle ergometers from different manufacturers. Due to the lack of consistency between Concept II BikeErg and Concept II RowErg PO, HR is better suited for the prescription of training loads on the BikeErg.


2018 ◽  
Vol 32 (12) ◽  
pp. 1043-1054 ◽  
Author(s):  
Nina Lefeber ◽  
Emma De Keersmaecker ◽  
Stieven Henderix ◽  
Marc Michielsen ◽  
Eric Kerckhofs ◽  
...  

Introduction. Physiological responses are rarely considered during walking after stroke and if considered, only during a short period (3-6 minutes). The aims of this study were to examine physiological responses during 30-minute robot-assisted and body weight–supported treadmill and overground walking and compare intensities with exercise guidelines. Methods. A total of 14 ambulatory stroke survivors (age: 61 ± 9 years; time after stroke: 2.8 ± 2.8 months) participated in 3 separate randomized walking trials. Patients walked overground, on a treadmill, and in the Lokomat (60% robotic guidance) for 30 minutes at matched speeds (2.0 ± 0.5 km/h) and matched levels of body weight support (BWS; 41% ± 16%). Breath-by-breath gas analysis, heart rate, and perceived exertion were assessed continuously. Results. Net oxygen consumption, net carbon dioxide production, net heart rate, and net minute ventilation were about half as high during robot-assisted gait as during body weight–supported treadmill and overground walking ( P < .05). Net minute ventilation, net breathing frequency, and net perceived exertion significantly increased between 6 and 30 minutes (respectively, 1.8 L/min, 2 breaths/min, and 3.8 units). During Lokomat walking, exercise intensity was significantly below exercise recommendations; during body weight–supported overground and treadmill walking, minimum thresholds were reached (except for percentage of heart rate reserve during treadmill walking). Conclusion. In ambulatory stroke survivors, the oxygen and cardiorespiratory demand during robot-assisted gait at constant workload are considerably lower than during overground and treadmill walking at matched speeds and levels of body weight support. Future studies should examine how robotic devices can be Future studies should examine how robotic devices can be exploited to induce aerobic exercise.


Life ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 586
Author(s):  
Ronam Toledo ◽  
Marcelo R. Dias ◽  
Ramon Toledo ◽  
Renato Erotides ◽  
Daniel S. Pinto ◽  
...  

The purpose of the present study was to compare the heart rate (HR), blood lactate and training load between different CrossFit® workouts, with equalized total work volumes in men and women. The study included 23 individuals (13 men and 10 women) experienced in CrossFit® training, who performed two workouts with different training types (as many reps as possible (AMRAP) and ‘for time’) but an equalized volume. Measurements of lactate, HR and rating of perceived exertion (RPE) were performed. The results show that there was no HR interaction between workout time and sex (p = 0.822; η2 = 0.006) and between workout type and sex (p = 0.064, η2 = 0.803). The HR significantly differed during each workout type (p < 0.001, η2 = 0.621), but not between the two workout types (p = 0.552, η2 = 0.017). Lactate showed no difference between the workout types (p = 0.474, η2 = 0.768), although the training load was higher (p = 0.033, η2 = 0.199) in women when they performed AMRAP. Altogether, the HR was not significantly different between training types or sex, while RPE, lactate and training load showed statistically significant differences depending on the group (women or men) or workout type (AMRAP or ‘for time’).


2009 ◽  
Vol 4 (2) ◽  
pp. 244-253 ◽  
Author(s):  
Michael J. Duncan ◽  
Mark Lyons ◽  
Joanne Hankey

Purpose:This study examined the placebo effect of caffeine on number of repetitions (reps), rating of perceived exertion (RPE), blood pressure (BP), and peak heart rate (PHR) during resistance-training exercise with repetitions (reps) performed to volitional failure.Methods:Following determination of 1-rep maximum in single-leg leg extension, 15 males performed reps to failure at 60% 1-RM in 3 conditions: control, perceived caffeine condition, and perceived placebo condition presented in a randomized order. Participants were informed they would ingest 250 mL of solution that contained either 3 mg·kg−1 caffeine or 3 mg·kg−1 placebo 1 h before each exercise trial. A deceptive protocol was employed and subjects consumed a placebo solution in both conditions. During each condition, total reps, RPE for the active muscle and overall body, and PHR were recorded.Results:Subjects completed 2 more reps when they perceived they had ingested caffeine. RPE was significantly (P = .04) lower in the perceived caffeine and control conditions and RPE for the active muscle was significantly higher across all conditions compared with RPE for the overall body. No substantial differences were evident in PHR across conditions.Conclusions:Results of this study are similar to studies of actual caffeine ingestion. However, the perception of consuming a substance that purportedly enhances performance is sufficient enough to enable individuals to complete a greater number of reps to failure during short-term resistance exercise.


2021 ◽  
pp. bjsports-2020-103758
Author(s):  
Simon Driver ◽  
Megan Reynolds ◽  
Katelyn Brown ◽  
Jakob L Vingren ◽  
David W Hill ◽  
...  

ObjectivesTo (1) determine if wearing a cloth face mask significantly affected exercise performance and associated physiological responses, and (2) describe perceptual measures of effort and participants’ experiences while wearing a face mask during a maximal treadmill test.MethodsRandomised controlled trial of healthy adults aged 18–29 years. Participants completed two (with and without a cloth face mask) maximal cardiopulmonary exercise tests (CPETs) on a treadmill following the Bruce protocol. Blood pressure, heart rate, oxygen saturation, exertion and shortness of breath were measured. Descriptive data and physical activity history were collected pretrial; perceptions of wearing face masks and experiential data were gathered immediately following the masked trial.ResultsThe final sample included 31 adults (age=23.2±3.1 years; 14 women/17 men). Data indicated that wearing a cloth face mask led to a significant reduction in exercise time (−01:39±01:19 min/sec, p<0.001), maximal oxygen consumption (VO2max) (−818±552 mL/min, p<0.001), minute ventilation (−45.2±20.3 L/min), maximal heart rate (−8.4±17.0 beats per minute, p<0.01) and increased dyspnoea (1.7±2.9, p<0.001). Our data also suggest that differences in SpO2 and rating of perceived exertion existed between the different stages of the CPET as participant’s exercise intensity increased. No significant differences were found between conditions after the 7-minute recovery period.ConclusionCloth face masks led to a 14% reduction in exercise time and 29% decrease in VO2max, attributed to perceived discomfort associated with mask-wearing. Compared with no mask, participants reported feeling increasingly short of breath and claustrophobic at higher exercise intensities while wearing a cloth face mask. Coaches, trainers and athletes should consider modifying the frequency, intensity, time and type of exercise when wearing a cloth face mask.


2000 ◽  
Vol 90 (2) ◽  
pp. 457-471 ◽  
Author(s):  
Sarah A. Schaeffer-Gerschutz ◽  
Lynn A. Darby ◽  
Kathy D. Browder

Overall ratings of perceived exertion, i.e., undifferentiated RPE, are often used as indicators of exercise intensity during walking, jogging, and cycling; however, conflicting results concerning RPE during aerobic dance exercise have been reported, and the use of differentiated RPE, i.e., local RPE and central RPE, has not been investigated. The purposes of this study were to assess local, central, and over-all RPE, and physiological responses [heart rate (HR); % HRmax; absolute and relative VO2; % VO2 max, ventilation (VE), ventilatory equivalent (VE · VO2−1); and oxygen pulse] during aerobic dance exercise varied by Arm Movement (Static Arm vs Dynamic Arm) and Impact (High vs Low). Trained women ( N = 25; max VO2 = 50.4± 7.5 ml · kg−1 · min.−1) completed four aerobic dance steps. No RPE were significantly correlated with heart rate or VO2; however, for all steps all RPE were significantly ( r = .40–,62) correlated with VE · VO2−1or VE. No interactions were present for RPE or physiological variables, and main effects were noted for Impact and Arm Movement. All RPE were greater for High Impact and for Static Arm Movement. Because VE and VE · VO2−1 were correlated with Overall RPE for all steps, this may suggest that participants “attended to” perceived changes in respiratory phenomena during aerobic dance exercise. It appears that during combined arm-and-leg aerobic dance exercise the use of Overall RPE is sufficient to assess perceptual sensations associated with the intensity of the exercise. Changes in Overall RPE were proportionate to objective measures of exercise intensity, i.e., HR and VO2; however, it is recommended that both HR and Overall RPE be used to assess fully a participant's objective and subjective responses during aerobic dance exercise.


Author(s):  
Ciaran O’Grady ◽  
Louis Passfield ◽  
James G. Hopker

Purpose: Rating of perceived exertion (RPE) as a training-intensity prescription has been extensively used by athletes and coaches. However, individual variability in the physiological response to exercise prescribed using RPE has not been investigated. Methods: Twenty well-trained competitive cyclists (male = 18, female = 2, maximum oxygen consumption =55.07 [11.06] mL·kg−1·min−1) completed 3 exercise trials each consisting of 9 randomized self-paced exercise bouts of either 1, 4, or 8 minutes at RPEs of 9, 13, and 17. Within-athlete variability (WAV) and between-athletes variability (BAV) in power and physiological responses were calculated using the coefficient of variation. Total variability was calculated as the ratio of WAV to BAV. Results: Increased RPEs were associated with higher power, heart rate, work, volume of expired oxygen (VO2), volume of expired carbon dioxide (VCO2), minute ventilation (VE), deoxyhemoglobin (ΔHHb) (P < .001), and lower tissue saturation index (ΔTSI%) and ΔO2Hb (oxyhaemoglobin; P < .001). At an RPE of 9, shorter durations resulted in lower VO2 (P < .05) and decreased ΔTSI%, and the ΔHHb increased as the duration increased (P < .05). At an RPE of 13, shorter durations resulted in lower VO2, VE, and percentage of maximum oxygen consumption (P < .001), as well as higher power, heart rate, ΔHHb (P < .001), and ΔTSI% (P < .05). At an RPE of 17, power (P < .001) and ΔTSI% (P < .05) increased as duration decreased. As intensity and duration increased, WAV and BAV in power, work, heart rate, VO2, VCO2, and VE decreased, and WAV and BAV in near-infrared spectroscopy increased. Conclusions: Self-paced intensity prescriptions of high effort and long duration result in the greatest consistency on both a within- and between-athletes basis.


2021 ◽  
Author(s):  
Helena Batatinha ◽  
Forrest L. Baker ◽  
Kyle A. Smith ◽  
Tiffany M. Zúñiga ◽  
Charles R. Pedlar ◽  
...  

AbstractAthletes are advised to receive the COVID-19 vaccination to protect them from SARS CoV-2 infection during major competitions. Despite this, many athletes are reluctant to get the COVID-19 vaccine due to concerns that symptoms of vaccinosis may impair athletic performance.OBJECTIVETo determine the effects of COVID-19 vaccination on the physiological responses to graded exercise.METHODSHealthy participants completed a 20-minute bout of graded cycling exercise before and ~21 days after COVID-19 vaccination (2 dose Pfizer mRNA or 1 dose Johnson & Johnson).RESULTSOxygen uptake, CO2 production, respiratory exchange ratio, ventilation, heart rate, serum noradrenaline, and rating of perceived exertion were significantly elevated in the post vaccine trial. However, vaccination did not affect serum lactate, adrenaline, cortisol, predicted , and ventilatory threshold. Post-vaccine effects on heart rate and noradrenaline remained significant in non-infected participants that received the Pfizer vaccine. No significant effects in respiratory gas exchange parameters were found after vaccination in those previously exposed to SARS-CoV-2, but exercise adrenaline levels were significantly lower and serum lactate levels trending (p= 0.10) lower after vaccination. No changes in any physiological responses to exercise were found in control participants who completed two bouts of exercise separated by ~5 weeks without vaccination.CONCLUSIONRecent COVID-19 vaccination is associated with modest increases in the physiological demands to graded exercise in non-infected healthy people but may actually improve metabolic responses to exercise in those previously infected with SARS-CoV-2. Whether or not these small effects could impact athletic performance at the elite level warrants investigation.


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