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PubMed1998

Effect of music on perceived exertion, plasma lactate, norepinephrine and cardiovascular hemodynamics during treadmill running.

We examined the effects of listening to headphone music in ten well trained men (25.1 +/- 6 years) during treadmill running. Maximal oxygen consumption, determined by open circuit spirometry, was followed by two submaximal work bouts 72 hours apart. The work bouts consisted of a supine rest, a 15 minute run at 70% of maximal oxygen consumption, and a three minute active recovery period. Participants listened to music during one of the two trials. Hemodynamic variables and perceived exertion were recorded at three minute intervals during each trial. A venous blood sample, obtained prior to and following each trial, was assayed for norepinephrine and plasma lactate. Analysis of variance revealed significant differences (p < 0.05) between the no music versus the exercise with music trial for (aggregate data 3,6,9,12,15 minutes): heart rate 152.9 +/- 5.3 to 145.9 +/- 4.7 beats x min(-1); systolic blood pressure, 158.1 +/- 3.7 to 151.7 +/- 3.3 mmHg; rate-pressure product 242.2 +/- 11.5 to 222.1 +/- 11.4; exercise lactate 2.75 +/- 0.15 to 2.13 +/- 0.18 mmol x l(-1); and perceived exertion 14.4 +/- 0.4 to 12.9 +/- 0.4. A 17.5% lower level of norepinephrine (841.5 +/- 314.7 to 694.1 +/- 254.5 pg x ml[-1]) in the exercise and music trial was not statistically significant (p<0.05); however a moderate effect size (ES = 0.52) was calculated and may be of practical significance considering the variability of the sample. Higher values for hemodynamics and lactate in the no music trial is suggestive of a greater metabolic demand; however, oxygen consumption was not different. Perhaps the music allowed individuals to relax reducing muscle tension thereby increasing blood flow and lactate clearance while decreasing lactate production in working muscle. The combined results of this study suggest the introduction of music has a psychobiological impact on the exerciser demonstrated by changes in perceived effort, lactate and norepinephrine.

Adult↗
PubMed1995

Relationships between perceived exertion and physiological variables during swimming.

The relationships between perceived exertion and the physiological variables oxygen uptake (VO2), heart rate (HR) and blood lactate concentration (HLa) were studied in tethered swimming. Seven male and ten female subjects swam at five submaximal intensities. The degree of perceived exertion was measured both on the category scale (RPE) and on the category-ratio scale (CR-10). All five dependent variables (VO2, HR, HLa, RPE and CR-10) were described by the equation R = a+c (S-b)n with the drag (D) in tethered swimming as an independent variable. The relationships between D and VO2, HR and RPE were linear with a level of fitness correlation (r = 0.989-0.999) for both males and females. The HLa exponents were 3.2 for males (r = 1.000) and 3.6 for females (r = 0.991), and CR-10 were 1.5 for males (r = 0.998) and 1.9 for females (r = 1.000), respectively. The growth functions for males and females were very similar. The conclusion is that RPE is effective as a measure of exercise intensity and can be used for exercise prescription in practical swimming.

Adult↗
PubMed1987

Lower limb asymmetry and patellofemoral joint incongruence in the etiology of knee exertion injuries in athletes.

The association between different knee exertion injuries and lower limb malalignments was studied in 121 male athletes with knee exertion injuries and in 20 male athletes without knee symptoms. The associations between different malalignments was also analyzed. Leg length inequality (LLI), knee valgus, and different indexes of patellofemoral joint congruence were measured using radiological methods. Male athletes with patellar apicitis (n = 59) had significantly more LLI (P less than 0.001) and patella alta (P less than 0.05) than athletes without knee symptoms. The knee valgus was of the same numerical value in the shorter and longer leg sides in subjects with LLI of at least 5 mm (n = 58). A positive correlation was found between lateral patellar displacement (LPD) and patella alta (LT/LP) (P less than 0.001). Negative correlations were found between the sulcus angle (SA) and the lateral patello-femoral angle (LPA) (P less than 0.001) as well as between the LPD and the LPA (P less than 0.001).

Adult↗
PubMed1993

Physical workload, perceived exertion, and output of cut wood as related to age in motor-manual cutting.

Physical workload, output of cut wood, and perceived exertion were studied among 15 younger (mean age 29 years) and 16 older (mean age 59 years) lumberjacks, using a chainsaw and paid on a piece-rate basis. Oxygen consumption was measured with portable equipment, while heart rate was measured telemetrically. The oxygen consumption for all working phases was 1.8 +/- 0.2 l/min (means +/- SD) (younger) and 1.5 +/- 0.2 l/min (older), which corresponded to 49 +/- 4% and 53 +/- 7% of maximal oxygen consumption estimated in ergometer bicycle exercise test. A negative relationship was found between relative oxygen consumption at work and maximal oxygen consumption (ml/kg/min). Mean heart rates for all working phases were 138 +/- 10 beats/min (younger) and 126 +/- 17 (older). The heart rate differed between the working phases, and was significantly higher for both groups during bunching than during the other operations. The output of cut wood did not differ significantly between the groups. Slight but significantly relationships were found between output of cut wood and maximal oxygen consumption (ml/kg/min) and oxygen consumption (ml/kg/min) during work. Rating of perceived exertion (RPE) and simultaneous heart rate recordings during cycle tests and field studies showed significant correlations between heart rate and RPE values during cycling in both groups. RPE values and heart rate in the field showed a slight correlation (younger) and not at all (older).

Adult↗
PubMed1994

A rapid appraisal of occupational workload from a modified scale of perceived exertion.

A simple and rapid method of determining occupational workload among Indian women performing manual activities was developed based on the strong relationship between physiological responses and subjective feeling of exertion. A modified five point scale of perceived exertion, sequentially numbered 1 to 5, was created to simplify the complicated and time-consuming procedures using conventional methods of measuring energy expenditure, or even heart rate responses, during work of very short duration, especially in field situations. The scale denotes physiological workload: 1: very light; 2: light; 3: moderately heavy; 4: heavy; and 5: very heavy. A job-classification table based on energy expenditure and heart rate responses is also proposed, and different household activities such as grinding masalas, dish washing, sweeping, mopping, ironing, storing water, etc. have been graded accordingly.

Adult↗
PubMed1997

A single metric for quantifying biomechanical stress in repetitive motions and exertions.

The relative effects of repetition, force and posture were studied in order to investigate how continuous biomechanical measurements can be combined into a single metric corresponding to subjective discomfort. A full factorial experiment was conducted involving repetitive wrist flexion from a neutral posture to a given angle against a controlled force. Seven subjects performed the task using two paces (20 and 4 motions/min), two force levels (15 and 45 N) and two angles (15 and 45 degrees) for 1 h each. Discomfort was reported on a 10 cm visual analogue scale anchored between 'no discomfort' and 'very high discomfort'. Repeated measures analysis of variance showed that all main effects were statistically significant (p < 0.05) and no significant interactions were observed. A linear regression model was fitted to the data and used for generating frequency weighted digital filters that shape continuous recordings of repetitive motions and exertions into an output proportional to relative discomfort. The resulting high-pass digital filter had a 22 dB/decade attenuation slope. A simulated industrial task used for validating the model involved repetitively transferring pegs across a horizontal bar and inserting them into holes against a controlled resistance. Angular wrist data were recorded using an electrogoniometer and filtered. Six subjects performed the task of the three conditions consisting of (1) 15 wrist flexion, 15 N resistance and 6 motions min, (2) 15 wrist flexion. 45 N resistance and 12 motions/min, and (3) 45 degrees wrist flexion, 45 N resistance and 15 motions/min. Subjective discomfort was reported after performing the task for 1 h. Pearson correlations between subjective discomfort ratings and the integrated filtered biomechanical data for individual subjects ranged from 0.90 to 1.00. The pooled correlation across subjects was 0.67. This approach may be useful for physical stress exposure assessment and for design of tasks involving repetitive motions and exertions.

Adult↗
PubMedDate not supplied

Energy expenditure, physical exertion and time allocation among Huli-speaking people in the Papua New Guinea Highlands.

OBJECTIVES: The study aimed to (1) elucidate the energetic adaptations of Huli people by comparing the three sub-populations in relation to their diversified natural and socioeconomic environment, based on energy expenditure and time allocation data; and (2) assess the applicability of a new index of physical exertion levels of activities (physical exertion index: PEI). RESEARCH DESIGN AND METHODS: Married males and females (n = 43) were selected, including 14 from a hilly village, 13 from a flat swampy village and 16 migrants to a town. Continuous heart rate (HR) monitoring, in conjunction with minute-by-minute observation of activities, was undertaken. Total energy expenditure was assessed by flex-HR method and physical activity level (PAL) was calculated as multiples of basal metabolic rate. Observed activities were divided into 15 categories and the PEI was calculated for each: PEI = (mean HR of a categorized activity)/(flex HR) x 100. RESULTS: No significant difference was found in PAL among the three sub-populations: 1.77, 1.92 and 1.81 for men and 1.78, 1.98 and 1.66 for women in hilly and flat villages, and a town, respectively. The comparison of the two village groups revealed that hilly terrain did not affect substantially the physical intensity of agricultural activities. On the other hand, the town migrants were engaged in sedentary paid jobs and these were less energy consuming than agricultural work. However, the different energy costs between paid jobs and agricultural work were offset by longer work time in the town group than in the two village groups (251 vs 50 or 70 min in males; 258 vs 152 or 138 min in females), resulting in similar PAL in the three groups. CONCLUSIONS: Despite contrasting natural and social environments, no significant difference was found in daily physical activity level among the three sub-populations (two villages and a town) of Huli-speaking people in Papua New Guinea Highlands.

Adult↗
PubMed2006

Exertional symptoms and exercise capacity in individuals with brain injury.

PURPOSE: To examine factors affecting cycling exercise performance in individuals with acquired brain injury. METHODS: Thirty individuals with acquired brain injury and 18 sedentary controls (SC) participated. Heart rate, bicycle power output and rating of perceived exertional (RPE) were recorded, throughout incremental cycle ergometer exercise. The SC group and 18 moderately impaired individuals from the ABI group performed a 25-W (B25) protocol. The remaining 12 individuals performed a 10-W protocol (B10). RESULTS: The B10 group terminated exercise at the lowest RPE, percentage age predicted maximal heart rate (% APMHR) and bicycle power output, followed by the B25 and then the SC group (RPE: Kruskal - Wallis test P < 0.001, %APMHR and bicycle power output: one-way ANOVA P < 0.01). RPE was correlated with %APMHR and percentage of peak bicycle output (B10 group: R2 0.1 to 0.67; B25 group: 0.69 - 0.83; SC group: 0.76 - 0.91). There was no difference in RPE at the same relative work intensity between the B25 and the sedentary control group (P > 0.05). Forward regression analysis revealed fatigue levels were predictive of %APMHR at test termination (beta = -0.411, P < 0.05) and quadriceps strength was predictive of peak bicycle power output (beta = 0.612, P < 0.05). CONCLUSIONS: Individuals with brain injury terminated exercise at lower exercise intensities but rated exertion no differently from healthy individuals. General fatigue levels predicted %APMHR and quadriceps strength predicted peak bicycle power output.

Adult↗
PubMed2000

Does heavy physical exertion trigger myocardial infarction? A case-crossover analysis nested in a population-based case-referent study.

To study possible triggering of first events of acute myocardial infarction by heavy physical exertion, the authors conducted a case-crossover analysis (1993-1994) within a population-based case-referent study in Stockholm County, Sweden (the Stockholm Heart Epidemiology Program). Interviews were carried out with 699 myocardial infarction patients after onset of the disease. These cases represented 47 percent of all cases in the study base, and 70 percent of all nonfatal cases. The relative risk from vigorous exertion was 6.1 (95% confidence interval: 4.2, 9.0). The rate difference was 1.5 per million person-hours, and the attributable proportion was 5.7 percent. The risk was modified by physical fitness, with an increased risk being seen among sedentary subjects as in earlier studies, but the data also suggested a U-shaped association. In addition, the trigger effect was modified by socioeconomic status. Premonitory symptoms were common, and this implies risks of reverse causation bias and misclassification of case exposure information that require methodological consideration. Different techniques (the use of the usual-frequency type of control information, a pair-matched analysis, and a standard case-referent analysis) were applied to overcome the threat of misclassification of control exposure information. A case-crossover analysis in a random sample of healthy subjects resulted in a relative risk close to unity, as expected.

Aged↗
PubMed1995

Exertional syncope in a patient with aortic stenosis and right coronary artery disease.

A female with advanced aortic valvular stenosis and moderate right coronary artery disease experienced an exertional syncope during 24-h ambulatory electrocardiographic monitoring. A progressive bradycardia with 90-s sinus node arrest (cardio-inhibitory response) and premonitory angina pectoris with significant ST segment changes were demonstrated. Our report supports the concept of a neurocardiogenic (vasovagal) mechanism of exertional syncope in patients with aortic stenosis. The predominant left ventricular inferior-wall myocardial ischaemia in our patient might be an additional stimulus to left ventricular mechanoreceptors, resulting in a profound cardio-inhibitory response.

Aged↗
PubMed1987

Variable threshold of exertional ischaemia in patients with positive exercise test at low workload.

In order to determine individual variability of ischaemic threshold on different days, 18 patients with exertional ischaemia at low workload were studied. All patients performed two exercise tests during different days in the morning and three on the same day at 9 am, 2 pm and 5 pm. The test performed in the morning on different days resulted in a significant difference in the mean values of rate pressure product at the ischaemic threshold as a consequence of individual variability observed in 10 patients. In 8 of these patients the differences were greater than 4000 mmHg beats min-1. Two patients showed respectively, 1 and 5 negative exercise tests despite the greater values of rate pressure product reached. Only 3 patients showed circadian variation of the ischaemic threshold; in these 3 patients variations of rate pressure product at the ischaemic threshold were also observed between different days. These data indicate that in patients with exertional ischaemia at low workload the rate pressure product at the ischaemic threshold shows considerable variability between tests performed on different days.

Angina Pectoris↗
PubMed1984

Perceived exertion. A review.

Physical therapists are well aware of the physiological responses to exercise. The process by which these underlying mechanisms contribute to the perceptual response of perceived exertion is generally less familiar. The purpose of this article is to summarize briefly some of the current major concepts about perceived exertion and to indicate, where possible, the potential significance of these concepts for physical therapy.

Heart Rate↗
PubMed1993

Joint hyperlaxity and musculoligamentous lesions: study of a population of homogeneous age, sex and physical exertion.

A total of 675 male soldiers of the same age (17 years) and on the same physical exertion regimen were studied in order to determine the incidence of joint laxity and its potential relationship to the appearance of musculoligamentous lesions. They were investigated during their 2-month military training period, which involved the same heavy physical exertion for all the individuals. The degree of joint laxity was determined on the basis of five criteria involving the hand, elbow, knee and spine. The overall population was divided into three groups according to the number of criteria met, namely: (1) normal or non-lax individuals, with none or only one criterion (67% of the studied population); (2) lax individuals, with two or three criteria (25.5%); and (3) hyperlax individuals, with four or five criteria (7.5%). The occurrence of musculoligamentous lesions during the 2-month study, particularly those involving the ankle and knee, was significantly more frequent in hyperlax and lax individuals than it was in their counterparts with normal joint mobility. These results confirm that joint hyperlaxity predisposes individuals to musculoligamentous lesions.

Adolescent↗
PubMed2004

Role of gastrointestinal permeability in exertional heatstroke.

Reduced splanchnic blood flow and hyperthermia during exercise-heat stress can produce gastrointestinal barrier dysfunction and increased gastrointestinal permeability. This may allow endotoxin to enter the internal environment, causing local and systemic immune responses. These responses may be involved in the cause and outcome of exertional heatstroke. Countermeasures may reduce gastrointestinal permeability and possibly exertional heatstroke occurrence and outcome.

Animals↗
PubMed1999

Exertional heat stroke: a case series.

UNLABELLED: Exertional heat stroke (EHS) is a state of extreme hyperthermia that occurs when excess heat that is generated by muscular exercise exceeds the body's ability to dissipate it at the same rate. EHS is thought to coincide with previously healthy, highly motivated, and relatively untrained individuals exerting in hot environments for long periods. PURPOSE: To establish this notion, the present study was aimed to follow the trends in the incidence of EHS in the period 1988-1996. METHODS: During these years, 150 cases of male soldiers (age = 20+/-3 yr) were reported to our institute as suffering from heat illnesses. According to the files, 82 cases were definitely diagnosed as EHS. RESULTS: More than 50% of the cases occurred during the first 6 months in service. Most of the cases occurred during the summer season (June-September), but 30% of the cases occurred during the spring. EHS was not related to time in the day. Many cases occurred during the night or early morning, even under mild heat load. Forty percent of the cases occurred during very short activities, and about 60% occurred already during the first 2 h of exercise. The results were discussed in view of the regulations which prevail in the Israeli army. CONCLUSIONS: It seems that almost all EHS cases occurred when regulations were not strictly followed.

Heat Stroke↗
PubMed2001

OMNI scale perceived exertion at ventilatory breakpoint in children: response normalized.

PURPOSE: The Children's OMNI Scale of Perceived Exertion was used to identify a response normalized rating of perceived exertion (RPE)-Overall, RPE-Legs, and RPE-Chest that corresponds to the ventilatory breakpoint (Vpt) in 8- to 12-yr-old female and male children. METHODS: Subjects were a priori stratified into two fitness groups on the basis of peak oxygen uptake (VO2 peak): average (A) (41.0-49.0 mL x kg(-1) x min(-1); N = 24) and above average (AA) (50.0-58.0 mL x kg(-1) x min(-1); N = 24). Vpt was determined by a progressive cycle ergometer protocol to VO2 peak. RESULTS: A gender effect was not observed for any descriptive or dependent variable. Mean VO2peak for the A group was 1.72 L x min(-1) and for the AA group 2.04 L x min(-1). Vpt corresponded to 64.0% VO2 peak for A and 74.0% VO2peak for AA. RPE-Overall (mean A and AA, 6.1), RPE-Legs (mean A and AA, 7.2), and RPE-Chest (mean A and AA, 4.5) did not differ between the fitness groups. CONCLUSION: Findings indicated that undifferentiated and differentiated RPE-Vpt were similar between female and male children who varied in VO2peak and Vpt. A comparatively stable RPE-Vpt for 8- to 12-yr-old children that vary in VO2peak and Vpt indicates a group normalized perceptual response.

Anaerobic Threshold↗
PubMed2002

Children's OMNI Scale of Perceived Exertion: walking/running evaluation.

PURPOSE: The Children's OMNI-walk/run Scale of Perceived Exertion (category range, 0-10) was evaluated using male and female children (6-13 yr of age) during a treadmill graded exercise test. METHODS: A cross-sectional, perceptual estimation paradigm using a walking/running test protocol was administered. Oxygen uptake (VO(2), mL x min(-1)), %VO(2max), ventilation (VE, L x min(-1)), respiratory rate (RR, breaths x min(-1)), respiratory exchange ratio (RER), heart rate (HR, beats x min(-1)), V(E)/VO(2) ratio, and ratings of perceived exertion (RPE) measurements were made every minute throughout the test. RESULTS: Significant correlations were found between OMNI-walk/run Scale RPE responses and VO(2), %VO(2max), HR, V(E)/VO(2) ratio, and RR throughout the maximal treadmill exercise test. The strongest correlations were found between RPE and %VO(2max) (r = 0.41-0.60, P < 0.001) and HR (r = 0.26-0.52, P < 0.01). CONCLUSION: The psychophysiological responses provide validity evidence for use of the Children's OMNI-walk/run Scale over a wide range of exercise intensities during both walking and running.

Adolescent↗
PubMedDate not supplied

The evaluation of mechanical devices for lateral transfers on perceived exertion and patient comfort.

PURPOSE: The purpose of this study was to compare the perceived physical stress felt by subjects (nursing and other hospital personnel), time spent, number of personnel required, and patient comfort using various methods to transfer patients laterally in the supine position. DESIGN: Descriptive comparative design. SAMPLE: One hundred ninety-two transfer ratings (132 using manual methods and 60 using a mechanical device) were compared. Thirty-two transfers (18 manual and 14 mechanical device) were timed, and 39 patients (12 having manual transfer and 27 with a mechanical device) provided comfort ratings. FINDINGS: Perceived exertion was significantly less for subjects performing lateral transfers with a mechanical device than with manual methods. Fewer personnel were needed for transfers with mechanical devices. Approximately 5 minutes less per transfer was needed when using mechanical devices, and patients felt significantly more comfortable and secure when a mechanical transfer device was used. DISCUSSION: The use of a mechanical device for transfer provided lower exertion ratings, used less personnel and time, and was more comfortable for patients. There are barriers to use, however, because of resistance to change, perceived increase in time needed for transfer, and the limitation of storing and retrieving the devices. Provision of equipment does not ensure use; institution of teaching and no-lift policies can facilitate use of lifting/transferring equipment.

Air↗