Project Aquarius 9. Relative Influence of Job Demands and Personal Factors on the Energy Expenditure, Strain, and Productivity of Men Suppressing Wildland Fires

1997 ◽  
Vol 7 (2) ◽  
pp. 159 ◽  
Author(s):  
GM Budd ◽  
JR Brotherhood ◽  
AL Hendrie ◽  
SE Jeffery ◽  
FA Beasley ◽  
...  
Keyword(s):  
Heart Rate ◽  
Energy Expenditure ◽  
Perceived Exertion ◽  
Sweat Rate ◽  
Fire Suppression ◽  
Job Demands ◽  
Personal Factors ◽  
Work Time ◽  
Subjective Responses ◽  
Hand Tool

Studies of hand-tool crews suppressing summer bushfires showed wide variations in firefighters' energy expenditure (EE) and productivity, and in their physiological and subjective responses ('strains'). Analyses of variance showed that (1) EE while using a rakehoe ('raking') varied mainly between subjects (i.e. with personal factors); (2) sweat rate, thigh skin temperature, and the proportion of the work time spent in each activity of fire suppression varied mainly between days of fireline construction (i.e. with job demands); and (3) heart rate, rectal temperature, perceived exertion, productivity, efficiency, and all-activities EE varied more or less equally between subjects and days, each of which explained about one third of the variation. These findings show that personal factors were no less influential than were the demands of the job.

Project Aquarius 7. Physiological and Subjective Responses of Men Suppressing Wildland Fires

1997 ◽  
Vol 7 (2) ◽  
pp. 133 ◽  
Author(s):  
GM Budd ◽  
JR Brotherhood ◽  
AL Hendrie ◽  
SE Jeffery ◽  
FA Beasley ◽  
...  
Keyword(s):  
Heart Rate ◽  
Energy Expenditure ◽  
Rectal Temperature ◽  
Thermal Environment ◽  
Sweat Rate ◽  
Work Practices ◽  
Subjective Responses ◽  
Hand Tool ◽  
Strenuous Work ◽  
Eucalypt Forests

The responses of four crews of 7-8 men were measured while they attempted to suppress well-developed experimental bushfires of intensities commonly faced by hand-tool crews, and also while they built fireline in the same way without fire, during three summers in dry eucalypt forests of SW and SE Australia. Average values were sweat rate 1,144 g h-1, heart rate (HR) 152 beats min-1, and rectal temperature (Tre) 38.2° C. Changes in the average temperatures of clothed and unclothed skin were negligible, indicating efficient evaporation of sweat. Firefighters considered the work 'somewhat hard', and felt 'just too warm' and 'wet' with sweat. By contrast, the responses of the scientific observers, doing less strenuous work in the same environment, were minimal: sweat rate 292 g h-1, HR 80 beats min-1, and Tre 37.6°C. Firefighters' responses were mainly due to exertion rather than fire, confirming an identical finding from measurements of their energy expenditure and thermal environment. Differences between attacks with and without fire were small in both groups (HR 8-9 beats min-1, Tre 0.1-0.2 degrees C) except for sweat rate (firefighters 401 g h-1, observers 181 g h-1), and were usually present before the attacks began. All responses were highly consistent over the four crews, three summers, and two regions. The above findings show that the firefighters worked within their capacity and paced themselves to sustain their own preferred equilibrium levels of strain. They also demonstrate the effectiveness of the firefighters' clothing and work practices.

Temperature effects on ventilatory rate, heart rate, and preferred pedal rate during cycle ergometry

1995 ◽  
Vol 79 (3) ◽  
pp. 781-785 ◽  
Author(s):  
F. Leweke ◽  
K. Bruck ◽  
H. Olschewski
Keyword(s):  
Heart Rate ◽  
Body Temperature ◽  
Perceived Exertion ◽  
Sweat Rate ◽  
Cycle Ergometer ◽  
O2 Uptake ◽  
Experimental Time ◽  
Physiological Variables ◽  
Pedal Rate ◽  
Rate Of Perceived Exertion

According to the most customary exercise protocols, core temperature (Tc) rises in parallel with workload (WL) and experimental time. Physiological variables, however, may be related to each of these factors. To investigate effects of WL independent of experimental time and body temperature, we employed four moderate WLs in 4-min steps between 35 and 65% peak O2 uptake (VO2 peak) in randomized order. To investigate independent effects of body temperature, the same work protocol was performed both after resting in comfortable ambient temperature [control test (Cont)] and after a double cold exposure [precooling test (Pret)], where Tc and the temperature set point are decreased by approximately 0.6 and 0.3 degrees C, respectively. Eight male subjects (24 +/- 1.9 yr, VO2 peak 4.9 +/- 0.5 l/min) worked on a cycle ergometer in a climatic chamber. Heart rate (HR) and breathing frequency (BF), but not preferred pedal rate (PR), were positively correlated to Tc, the slopes amounting to 17 and 3.75 min-1/degree C for HR and BF, respectively. The regression appeared linear over the whole temperature range, and the regression lines were not shifted by precooling. PR was increased by time, but Pret-Cont differences of PR and Tc were inversely correlated (r = -0.50, P < 0.01). The effects of WL were highly significant on HR, O2 uptake, and rate of perceived exertion but not on BF, PR, and sweat rate. The relation of rate of perceived exertion to HR was shifted by precooling.

Physiological Demand, Metabolic Requirements, and User-Perceived Exertion of Immersive Virtual Reality Exergaming Incorporating an Adaptive Cable Resistance System: An Exploratory Study (Preprint)

2021 ◽  
Author(s):  
Jonathan Hu ◽  
Jonathan D Browne ◽  
Michael T Arnold ◽  
Anthony Robinson ◽  
Marin F Heacock ◽  
...  
Keyword(s):  
Physical Activity ◽  
Heart Rate ◽  
Virtual Reality ◽  
Energy Expenditure ◽  
Perceived Exertion ◽  
Rating Of Perceived Exertion ◽  
Immersive Virtual Reality ◽  
Metabolic Equivalents ◽  
Physiological Demand ◽  
Resistance System

BACKGROUND The intersection of games and exercise has sparked the growth of novel training systems with the potential to promote quality physical activity. Innovations in Immersive Virtual Reality (IVR) have propelled “exergaming” to the forefront of the fitness landscape. Researchers have yet to fully explore the physiological and metabolic efficacy and applications of the immersive environment and interactive programming. OBJECTIVE This study aimed to measure metabolic (i.e., energy expenditure (EE)) and physiological (i.e., heart rate (HR)) demands and subjective fatigue and enjoyment scores during a signature 30-minute IVR adaptive cable resistance exergaming session. METHODS Fourteen healthy, college-aged individuals (7 females) were initially acquainted with the equipment and acclimated to the virtual reality and gameplay dynamics. Participants then completed a signature 30-minute exergaming session using an IVR adaptive cable resistance system (Black Box VR ®) that incorporated chest press, squat, row, lat pulldown, overhead press, and stiff leg deadlift. During the session, a portable metabolic gas exchange analysis system assessed energy expenditure by indirect calorimetry and a chest-worn monitor captured heart rate. Immediately following the session, participants completed questionnaires including the Borg scale for Rating of Perceived Exertion (RPE), the Physical Activity Enjoyment Scale (PACES), and the Simulator Sickness Questionnaire (SSQ). RESULTS EE was greater in males compared to females in terms of kcal/min (P = 0.001), total kcal (P = 0.001), and metabolic equivalents (P = 0.029). Females demonstrated a higher average HR (P = 0.020) and HR as a percentage of theoretical HRmax (P = 0.018). The overall mean metabolic equivalent (MET) during the session was 12.9 (0.5). Men achieved greater volume of total weight lifted during the session (P < 0.001) and with chest press (P = 0.005), overhead press (P = 0.001), stiff-leg deadlift (P = 0.002), and squat (P = 0.015). For the questionnaires, the mean (SD) of RPE, PACES and SSQ was 14 (1), 4.31 (0.36) and 24.04 (24.13), respectively. CONCLUSIONS IVR exergaming with resistance cable training elicits substantial EE and very high physiological demand while attenuating perceived psychological and physical fatigue. Further investigations of IVR utility should explore nuanced muscle recruitment patterns during training and long-term regimen adherence.

scholarly journals Impaired Heat Adaptation From Combined Heat Training and “Live High, Train Low” Hypoxia

2019 ◽  
Vol 14 (5) ◽  
pp. 635-643 ◽  
Author(s):  
Erin L. McCleave ◽  
Katie M. Slattery ◽  
Rob Duffield ◽  
Philo U. Saunders ◽  
Avish P. Sharma ◽  
...  
Keyword(s):  
Heart Rate ◽  
Oxygen Uptake ◽  
Core Temperature ◽  
Perceived Exertion ◽  
Sweat Rate ◽  
Cardiovascular Responses ◽  
Sodium Concentration ◽  
Peak Oxygen Uptake ◽  
Submaximal Heart Rate ◽  
Independent Heat

Purpose: To determine whether combining training in heat with “Live High, Train Low” hypoxia (LHTL) further improves thermoregulatory and cardiovascular responses to a heat-tolerance test compared with independent heat training. Methods: A total of 25 trained runners (peak oxygen uptake = 64.1 [8.0] mL·min−1·kg−1) completed 3-wk training in 1 of 3 conditions: (1) heat training combined with “LHTL” hypoxia (H+H; FiO2 = 14.4% [3000 m], 13 h·d−1; train at <600 m, 33°C, 55% relative humidity [RH]), (2) heat training (HOT; live and train <600 m, 33°C, 55% RH), and (3) temperate training (CONT; live and train <600 m, 13°C, 55% RH). Heat adaptations were determined from a 45-min heat-response test (33°C, 55% RH, 65% velocity corresponding to the peak oxygen uptake) at baseline and immediately and 1 and 3 wk postexposure (baseline, post, 1 wkP, and 3 wkP, respectively). Core temperature, heart rate, sweat rate, sodium concentration, plasma volume, and perceptual responses were analyzed using magnitude-based inferences. Results: Submaximal heart rate (effect size [ES] = −0.60 [−0.89; −0.32]) and core temperature (ES = −0.55 [−0.99; −0.10]) were reduced in HOT until 1 wkP. Sweat rate (ES = 0.36 [0.12; 0.59]) and sweat sodium concentration (ES = −0.82 [−1.48; −0.16]) were, respectively, increased and decreased until 3 wkP in HOT. Submaximal heart rate (ES = −0.38 [−0.85; 0.08]) was likely reduced in H+H at 3 wkP, whereas CONT had unclear physiological changes. Perceived exertion and thermal sensation were reduced across all groups. Conclusions: Despite greater physiological stress from combined heat training and “LHTL” hypoxia, thermoregulatory adaptations are limited in comparison with independent heat training. The combined stimuli provide no additional physiological benefit during exercise in hot environments.

Project Aquarius 10. Effects of Work, Weather, and Fire on the Energy Expenditure, Strain, and Productivity of Men Suppressing Wildland Fires

1997 ◽  
Vol 7 (2) ◽  
pp. 167 ◽  
Author(s):  
GM Budd ◽  
JR Brotherhood ◽  
AL Hendrie ◽  
SE Jeffery ◽  
FA Beasley ◽  
...  
Keyword(s):  
Heart Rate ◽  
Energy Expenditure ◽  
Regression Analyses ◽  
Deep Body Temperature ◽  
Hand Tool ◽  
Wide Range ◽  
Work Duration ◽  
Eucalypt Forests ◽  
Deep Body ◽  
Current Heat

Four crews of male firefighters were studied while they attempted to suppress well-developed experimental bushfires of intensities commonly faced by hand-tool crews, and also while they built fireline in the same way without fire, during three summers in Australian eucalypt forests. Multiple-regression analyses of their responses showed that they maintained their deep body temperature and heart rate at constant and sustainable levels over a wide range of work duration and intensity, and of heat from weather and fire that frequently exceeded the limits recommended in current heat-stress guidelines. Energy expenditure declined slightly with warmer weather and fire although not with rake duration. Productivity was unchanged by warmer weather but declined slightly with rake duration and with fire. The findings confirm the effectiveness of the firefighters' work practices that allowed them to set their own pace, and of their light, well ventilated clothing that permitted unrestricted evaporation of sweat.

scholarly journals Energy Expenditure during Acute Weight Training Exercises in Healthy Participants: A Preliminary Study

2021 ◽  
Vol 11 (15) ◽  
pp. 6687
Author(s):  
Muhammad Adeel ◽  
Chien-Hung Lai ◽  
Chun-Wei Wu ◽  
Jiunn-Horng Kang ◽  
Jian-Chiun Liou ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Energy Expenditure ◽  
Energy Cost ◽  
Perceived Exertion ◽  
Weight Training ◽  
Trained Group ◽  
Training Experience ◽  
Rate Of Perceived Exertion ◽  
Training Exercises

Energy expenditure during weight training exercises produces great fitness and health benefits for humans, but few studies have investigated energy expenditure directly during weight training. Therefore, in this study, we aimed to determine energy costs during three training sessions consisting of three different exercises. Ten participants were randomly allocated into two groups: an untrained (n = 5, with no weight training experience) and a trained group (n = 5, with some weight training experience). Each participant completed three training sessions on separate days. While wearing a mask for indirect calorimetric measurements, each participant participated in training sessions conducted with three dumbbell exercises: the bent-over row, deadlift, and lunge. Metabolic equivalents (METs), energy expenditure (EE), respiratory exchange ratio (RER), heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and rate of perceived exertion (RPE) were measured. The total energy cost was calculated from the oxygen consumption (VO2) during each exercise. Our results showed that the METs of a single training session were 3.3 for the untrained group and 3.4 for the trained group, while the sum of the EE was 683–688 and 779–840 kcal, respectively. The physiological parameters, such as heart rate (p = 0.001 *) for the lunge and rate of perceived exertion (p = 0.005 *) for the bent-over row, changed significantly in both groups. It was concluded that the exercise protocol of this study involved a moderate intensity of 2.4–3.9 METs. The energy cost of each training exercise was between 179 and 291 kcal.

scholarly journals Acute Physiological and Metabolic responses for 40-minutes of Samba Dance

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Paulo R. Santos-Silva ◽  
Cicera C. Duarte ◽  
Bruna B. Osorio ◽  
Julia Maria D.A. Greve ◽  
Guilherme V. Guimaraes
Keyword(s):  
Physical Activity ◽  
Heart Rate ◽  
Energy Expenditure ◽  
Sports Medicine ◽  
Perceived Exertion ◽  
Metabolic Response ◽  
Cardiopulmonary Exercise Test ◽  
Peak Exercise ◽  
Metabolic Equivalent ◽  
Health Promoting

Dance is an enjoyable health-promoting physical activity that many people worldwide incorporate into their lifestyles today. Therefore, dance improves your heart health, overall muscle strength, balance, and coordination, and reduces depression. We aim to gain insights into the effects of samba dance on the cardiorespiratory and metabolic response during an acute session of this dance style for 40-minutes. The study was carried out on 20 female samba dancers. All of them performed two procedures: (1) a cardiopulmonary exercise test on a treadmill for physical fitness aptitude verification and (2) a 40-minutes of samba dancing monitored by analysis of expired gases. The results were: At peak exercise: oxygen uptake (VO2) =32.7 mL.kg-1.min-1; heart rate (HR) =183 bpm; the pulse of oxygen (PO2) =10.9 mL.HR-1, energy expenditure (EE) = 9.9 kcal.min-1and metabolic equivalent (METs)=13.5.Overall, each session of the dance of 40-minutes was performed at a mean VO2 of 22.8 mL.kg-1.min-1 (70%VO2max), heart rate of 162 bpm (89%HRmax), energy expenditure (EE) of 6.5 kcal.min-1 (66%max), metabolic equivalent (METs) of 6.3 (62%max), and the rate of perceived exertion (RPE) of 11.8/20. In conclusion: The findings of the current investigation might suggest that the moderate and vigorous-intensity of the exercise verified in an acute samba dance session is enough to induce a chronic training effect recommended by the criteria established by the American College of Sports Medicine for improving cardiorespiratory fitness. This information may lead to a better understanding of the energy expenditure of samba dance and add to the compendium of physical activity. 

scholarly journals Heart rate and energy expenditure during garbage collection in Rio de Janeiro, Brazil

2007 ◽  
Vol 23 (11) ◽  
pp. 2749-2755 ◽  
Author(s):  
Luiz A. Anjos ◽  
João A. Ferreira ◽  
Jorginete J. Damião
Keyword(s):  
Heart Rate ◽  
Developing Countries ◽  
Energy Expenditure ◽  
Rio De Janeiro ◽  
Garbage Collection ◽  
Limited Information ◽  
Work Time ◽  
Health Related Research ◽  
Health Related

Physiological workload is used to estimate the physical demand of tasks in the workforce, but limited information is available for the various work activities in developing countries. Eighty-three randomly selected male workers participated in the present study, aimed at assessing the physiological workload of garbage collection (GC) in Rio de Janeiro, Brazil. Heart rate (HR) was obtained on four consecutive workdays. Energy expenditure (EE) was extrapolated from heart rate data based on individual laboratory-established heart rate/oxygen consumption curve in 70 workers. Mean HR during GC was 104.0 ± 11.7bpm (± SD), representing 56.9 ± 7.5% of maximum heart rate. EE was 1608.3 ± 738.5kcal for an average of 293.1 ± 103.9 minutes of work per day. Based on all measurements, work in garbage collection in Rio de Janeiro can be considered excessively heavy. These data emphasize the need to develop appropriate classification of workload to be used in health-related research and in the development of maximum acceptable work time in association with the physiological workload, particularly in developing countries.

scholarly journals The Intensity and Energy Expenditure of Exertions, Restitution Speed, and Rate of Perceived Exertion after Tournament Matches in Polish Futsal Players

2017 ◽  
Vol 18 (1) ◽  
Author(s):  
Paweł Wolański ◽  
Jarosław Muracki ◽  
Dawid Goliński ◽  
Jarosław Nosal ◽  
Ewa Bakońska-Pacoń ◽  
...  
Keyword(s):  
Heart Rate ◽  
Energy Expenditure ◽  
Perceived Exertion ◽  
Team Sport ◽  
Warm Up ◽  
Rate Of Perceived Exertion ◽  
Very High

AbstractPurpose. Futsal is a very dynamic indoor team sport. Like in soccer, futsal players perform a number of efforts of different intensity during a match. In each match there are a few return substitutions to allow players to have some rest. The aim of the study was to assess the intensity and energy expenditure of single efforts and the dynamics of restitution after the efforts during successive futsal matches.Methods. The study consisted in measuring the players′ (n = 11) heart rate (HR) during four matches: A, B, C, D. The HR measurement started during a pre-match warm-up and ended 5 min after the match.Results. The highest intensity of single efforts was noticed in match A. It equalled 90.22 ± 4.90% HRConclusions. The intensity was very high, much higher than that of players′ efforts in 11-a-side soccer. It should be concluded that an appropriate reduction in the time players spend on the pitch during their successive efforts in one match and the consecutive tournament matches can result in reducing the decrease in the effort intensity.

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