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PubMed2000

Oxygen cost for cycling as related to leg mass in males and females, aged 20 to 80.

In order to evaluate the determinants of the metabolic cost for cycle ergometry, we analyzed the relationship between VO2 and leg mass (LM) and total body mass (TBM) in 71 randomly-selected sedentary subjects (34 men), aged 20 to 80. Participants performed constant work rate (WR) tests at 0, 25, and 50 W (at 60 rpm) for 6 minutes in a randomized sequence: gross VO2, gross efficiency, and work efficiency were related to TBM and LM as assessed by dual energy x-ray absorptiometry. We found that gross VO2 and gross efficiency were more strongly related to LM than TBM but work efficiency values were independent of both (P>0.05). Significantly higher values of VO2TBM were found in subjects with large LM/TBM ratios and vice-versa; VO2/LM, however, did not change with anthropometric characteristics. Gross VO2 (mL/min) was predicted by a LM-based equation (10.6 [WR, W] + 16.8 [LM, kg] +75) with a mean error below 5%: this equation predicted the cost more accurately than previous TBM-based formulations (P<0.01). We conclude that leg mass actually provides the preferred frame of reference for predicting the oxygen cost for cycle ergometry at 60 rpm in sedentary subjects, independent of age or gender.

Absorptiometry, Photon↗
PubMed2002

[Effects of an optimized exercise therapy on physical performance of patients with cystic fibrosis].

Regular exercise training can increase the physical performance of patients with cystic fibrosis (CF). However, training is often hampered by negative factors such as infections, lack of time, etc. The aim of the present study was to investigate the effects of a 3-week-training-program performed under favourable conditions on physical performance and lung function of CF-patients: 17 patients daily trained at least 2,5 h under suspicious conditions at a sport hotel in Israel (Eilat). During the entire 3 weeks a comprehensive care was applied to the patients including intensive physical therapy and nutrition adapted to the individual demands. Testings of lung function and cycle ergometry ramp tests were performed a week before and after the training program. Additional control measurements were taken 7 months post training. After the 3-week-training vital capacity and FEV1 were increased by 7 % and 6 % (p > 0.05). The results of the cycle ergometry showed bigger and significant improvements in the maximal values of power (12 % - 20 %), oxygen uptake and ventilation. This findings were also valid for the submaximal exercise range indicated by a slower heart rate slope and a lower aerobic-anaerobic threshold. The present results suggest, that relatively large increases in physical performance can be obtained by short, but intensive exercise training including a comprehensive care.

Cystic Fibrosis↗
PubMed2004

The physiological responses to running after cycling in elite junior and senior triathletes.

The purpose of this investigation was to compare the physiological responses in cycling and the energy cost (EC) of running after cycling in elite junior (J (male) and J (female)) and senior (S (male) and S (female)) triathletes and to determine the relationship between laboratory physiological parameters and performance in an elite "standard" distance triathlon. Thirty-one elite triathletes competing at World Championship level (age: 23.4 +/- 4.8 y; height: 172.6 +/- 6.8 cm; body mass: 64.4 +/- 7.2 kg; V.O (2)max = 67.8 +/- 8.3 ml x kg (-1) x min (-1)) comprising J (male) (n = 7), J (female) (n = 6), S (male) (n = 9) and S (female) (n = 9) athletes performed a laboratory trial that consisted of submaximal treadmill running (to determine EC), maximal then submaximal cycle ergometry (to determine the peak power output [PPO], V.O (2)max, the ventilation threshold [VT] and cycling economy) followed by an additional submaximal running bout. Swimming, cycling, running and overall race performance (min) over a standard event was also measured in the field. S (male) had a faster cycle, run and overall triathlon times than J (male). S (female) demonstrated a faster cycle and overall triathlon time than J (female). The V.O (2)max (74.7 +/- 5.7 vs. 74.3 +/- 4.4 and 60.1 +/- 1.8 vs. 61.0 +/- 5.0 ml x kg (-1) x min (-1)) and cycling economy (72.5 +/- 4.5 vs. 73.8 +/- 4.3 and 75.6 +/- 4.5 vs. 79.8 +/- 9.8 W x l (-1) x min (-1)) were similar between the junior and senior, in both male and female triathletes. However, S (female) possessed a significantly higher PPO than J (female). S (male) had a higher VT (%V.O (2)max) than J (male) whereas the VT was similar in J (female) and S (female). There were no significant differences in EC change from the first to the second running bout between J (male) and S (male), whereas, in contrast, J (female) exhibited a significantly (p < 0.05) higher difference in EC than S (female). When all subjects were pooled, the overall triathlon time (min) was significantly correlated to V.O (2)max (r = -0.80; p < 0.001) and PPO (W) (r = -0.85; p < 0.001) in cycle ergometry. In conclusion, elite senior triathletes can be distinguished from their younger (junior) counterparts, mainly by a higher PPO in cycling and a lower increase in the whole body energy cost of running after cycling in female and by a higher ventilatory threshold in male triathletes.

Adolescent↗
PubMed1992

Anaerobic and aerobic power in arms and legs of elite senior wrestlers.

UNLABELLED: The purpose of this study was to characterize anaerobic power and aerobic power (power at peak oxygen uptake, or peak VO2) of elite senior (post-collegiate) wrestlers. Subjects (n = 14) from the U.S. national senior freestyle and Greco Roman wrestling teams were evaluated at separate tests using cycle ergometry for peak VO2 of the arms, peak VO2 of the legs, arm anaerobic peak power, and leg anaerobic peak power. Power output at peak VO2 was recorded for each test and compared to the anaerobic power of the appropriate body segment. The results (mean +/- SD) showed that wrestlers produced 2.3 +/- 0.4 W.kg body weight-1 at arm peak VO2 (43.7 +/- 4.6 ml.kg body weight-1. min-1), 4.2 +/- 0.5 W.kg body weight-1 at leg peak VO2 (50.9 +/- 5.1 ml.kg body weight-1.min-1), arm PP of 7.7 +/- 1.0 W.kg body weight-1, and leg PP of 10.5 +/- 1.7 W.kg body weight-1. Comparing power output during anaerobic and aerobic tests, the subjects performed at 3.4 +/- 0.6 times their peak oxygen uptake during arm anaerobic ergometry, whereas leg anaerobic peak power was 2.7 +/- 0.4 times the power at peak oxygen uptake for the legs (p < 0.05 for difference between ratios). CONCLUSION: relative to aerobic power, elite senior wrestlers may produce power anaerobically in the upper body at significantly higher levels than in the lower body.

Adult↗
PubMed1996

Assessment of the reproducibility of performance testing on an air-braked cycle ergometer.

The purposes of this study were (I) to assess the reproducibility of endurance performance testing on an air-braked cycle ergometer, and (II) to compare laboratory performances to performances in road races. Ten well-trained, competitive cyclists (peak power output [PPO] 443 +/- 37 W, [values are mean +/- SD]) undertook either: (I) three 20 km and three 40 km time trials (TT) on an air braked ergometry system (Kingcycle) (n = 6), and/or (II) three 40 km laboratory TT and two 40 km road TT competitions (n = 8). The time taken for the laboratory simulated 20 km and 40 km TT rides were highly reproducible (coefficient of variation 1.1 +/- 0.9% and 1.0 +/- 0.5%, respectively). However, the mean power output and heart rate were significantly different (p < 0.0001) between the 20 km and 40 km TT (327.5 +/- 16.9 vs 303.9 +/- 14.9 W and 171.4 +/- 5.1 vs 168.3 +/- 4.4 beats/min, respectively). A strong relationship (r = 0.99, p < 0.001) was observed between the mean cycling time and the average sustained power output. A significant correlation (r = 0.98, p < 0.001) was also observed between laboratory and road race times, although road race times were, on average, some 8% slower. These findings indicate that the Kingcycle ergometry system can be used as a reliable method of assessing short term endurance cycling performance.

Bicycling↗
PubMed1984

A high velocity treadmill running test to assess endurance running potential.

The power-endurance time curve described for cycle ergometry has been examined with respect to high velocity treadmill running to exhaustion. On a cycle ergometer, a hyperbolic function has been described that can be linearized by expressing power relative to the inverse of time to exhaustion. The mathematical relationship of this linear function is P = W'/t + theta f, where P = power output, W' = slope of regression, and theta f = fatigue threshold (intercept of power output). Six cross-country runners took part as subjects. Each ran to exhaustion with the treadmill at 6 different velocities between 19.2 and 22.4 km/h. The linear regressions fitted to velocity versus 1/time had correlation coefficients between r = 0.979 and 0.997. It was concluded that the treadmill velocity-endurance time relationship for runs of 2-12 min duration conformed to a similar hyperbolic function as that described for cycle ergometry. The two parameters W' and theta f might provide valuable indices of physical performance potential, which can be used to monitor training responses in competitive runners.

Adult↗
PubMed1984

Oxygen consumption and speed of cycling using an air-resistance simulator on a hometrainer roller.

Oxygen consumption was determined for subjects cycling on a hometrainer roller with a racing bicycle. In part of the experiments the bicycle was supplied with an air-resistance simulator. The relation between oxygen consumption and velocity of cycling on the roller is linear: similar to that during bicycle ergometry. The relation is almost the same as during bicycling outdoors on a touring bicycle when the simulator is used while cycling on the roller. Cycling with the simulator only on the bicycle on a support is comparable to cycling outdoors on a racing bicycle. It is concluded that the use of a roller and an air-resistance simulator can be used for ergometry and training.

Air Movements↗
PubMed1982

Serum FSH, LH, and testosterone in humans after physical exercise.

The serum levels of FSH, LH, and testosterone were determined by radioimmunoassay in 63 men before, during, and after maximal and submaximal physical short- and long-term exercise (800-n running, climbing, 36-k cross-country skiing). In the 800-meter run, significant elevations of FSH, LH, and testosterone were observed, while in all other field and laboratory test (climbing, 36-km cross-country skiing, maximal stepwise bicycle and treadmill ergometry, 90-min submaximal bicycle ergometry) the hormone levels remained unchanged or were decreased. In contrast to FSH and LH, which did not show any clear modification with duration or intensity of exercise or with the state of training, changes of testosterone in the endurance field test (36-km cross-country skiing) seemed to be training dependent. In highly endurance-trained subjects, there was an increase and in less well-trained subjects a decrease of testosterone for equal distances and intensities of exercise.

Adolescent↗
PubMed1991

[Fitness for swimming after myocardial infarct].

Standardized telemetry during swimming and blood pressure monitoring were performed on 25 consecutive patients (22 men and 3 women: mean age 59 +/- 7 years) after myocardial infarction, sustained on average 28 +/- 26 months ago. Mean exercise tolerance, as judged by symptoms during bicycle ergometry, was 1.31 +/- 0.5 W/kg (pulse limit 117 +/- 21 beats/min). The swimming test had to be discontinued in six patients because of severe arrhythmias, in two because of severe angina. Seven patients completed the full swimming distance, but were also considered unsuitable for swimming because of moderate angina and dyspnoea. Ten patients proved to be fit for swimming. Their average ergometrically determined exercise tolerance (1.27 +/- 0.51 W/kg, pulse limit 114 +/- 16 beats/min) was not different from that of unfit patients (1.34 +/- 0.50 W/kg; 119 +/- 24 beats/min). During swimming the unfit patients had a significantly higher heart rate and blood pressure rise than the fit ones. Only in the unfit patients the exercise tolerance limit determined by bicycle ergometry was exceeded during swimming. This indicates that postinfarction patients should undergo swimming telemetry before declared fit for swimming.

Angina Pectoris↗
PubMed1980

[Acebutolol in coronary heart disease: an ergometric double-blind study (author's transl)].

In 20 patients with coronary heart disease and typical changes in the exercise ECG (evidence of myocardial hypoxia), which disappeared completely on second ergometry after isosorbid dinitrate, the effect of a single dose of 400 mg acebutolol (Prent) was tested on exercise. Ergometrically induced cardiac work was significantly reduced in all patients, compared with leg exercise (little change in lower, more marked change in the higher ranges of exercise) so that repeat ergometry at the same ergometric level of exercise produced neither signs of hypoxia nor angina. There were no significant changes after a placebo.

Acebutolol↗
PubMed2003

Home-based versus hospital-based exercise programs in patients with coronary artery disease: effects on coronary vasomotion.

BACKGROUND: In a randomized study, we recently documented that a vigorous, hospital-based exercise training (ET) program improves coronary endothelial function in coronary artery disease. The aim of this consecutive study was to assess whether a home-based exercise program with reduced average training duration can sustain previously achieved effects on coronary endothelial function. METHODS: Nineteen patients with coronary endothelial dysfunction documented by acetylcholine-induced vasoconstriction were randomly assigned to a training group (n = 10) or a control group (n = 9). After 4 weeks of inhospital training (60 min of bicycle ergometry per day), all training patients were enrolled in a 5-month home-based program of 20 minutes' ergometry training per day and 1 group training session per week. At baseline, after 4 weeks and 6 months, endothelium-mediated vasodilation was assessed by quantitative coronary angiography after intracoronary infusions of acetylcholine. Average peak velocity (APV) was measured with a Doppler wire. Coronary blood flow (CBF) was calculated by multiplying vascular cross-sectional area and APV. RESULTS: CBF increased in response to 7.2 microg/min acetylcholine, from 27% +/- 11% at the beginning of the study to 110% +/- 24% after 4 weeks (P <.01 vs control group). After 6 months, the increase in CBF was lower versus inhospital training (67% +/- 18%, P <.05 vs 4 weeks). Changes in APV between 1 and 6 months correlated with daily training durations (r = 0.65, P =.03). CONCLUSIONS: Home-based ET sustained part of the effects of hospital-based ET on endothelium-dependent vasodilation in coronary artery disease. However, acetylcholine-induced increases in CBF were lower after home-based ET, suggesting a relation between daily training duration and improvement of coronary vasomotion.

Aged↗
PubMedDate not supplied

Relationship between different indices of exercise capacity and clinical measures in patients with chronic obstructive pulmonary disease.

PURPOSE: The purpose of this study was to make comparisons between different types of exercise tests used in chronic obstructive pulmonary disease (COPD) to better interpret the results and to select the most suitable testing procedure. Therefore, we evaluated the relationship between exercise capacity and other clinical measures and their relative contributions to exercise capacity in patients with COPD. METHOD: We studied 36 patients with stable COPD. All patients underwent baseline pulmonary function testing. Dyspnea during activities of daily living was assessed with the Oxygen Cost Diagram (OCD). The Hospital Anxiety and Depression Scale and the St George's Respiratory Questionnaire were used to assess psychologic status and health-related quality of life, respectively. All patients performed the 6-minute walking test, progressive cycle ergometry, and the cycle endurance test. RESULTS: Each exercise capacity result correlated significantly with pulmonary function, the OCD, and the Activity and Total scores of the St George's Respiratory Questionnaire. Multiple regression analyses revealed that the OCD was an important predictor of exercise capacity, especially for the walking test. Diffusing capacity was also a significant predictor on progressive cycle ergometry. Body mass index was the most significant predictor of the endurance time. CONCLUSION: The 3 different exercise tests had similar characteristics in relation to pulmonary function, dyspnea, and health-related quality of life in patients with COPD. However, some differences were found in the aspects they evaluated.

Aged↗
PubMed1990

Perspectives on cardiovascular fitness and SCI.

The purpose of these papers is to review and discuss the fundamental concepts and problems underlying cardiovascular fitness and spinal cord injury. Particular attention is paid to several modes of exercise available to individuals with spinal cord injury (SCI)--voluntary arm-crank and wheelchair ergometry, electrical stimulation leg cycle ergometry, and combined voluntary arm-cranking and electrical stimulation leg (hybrid) exercise. The effects of level of injury, active muscle mass, and sympathetic dysfunction upon acute central hemodynamic adjustments during exercise testing and chronic training adaptations are discussed for both quadriplegics and paraplegics. Several topics for future research are suggested.

Cardiovascular System↗
PubMed2007

The weighted walking test as an alternative method of assessing aerobic power.

The aim of the present study was to determine maximal oxygen uptake (VO2max) directly during uphill walking exercise and to compare these values with those achieved during running and cycling exercise. Forty untrained students (20 males and 20 females) took part in three exercise tests. The running test was performed on a horizontal treadmill and the speed was gradually increased by 0.3 m . s(-1) every 3 min. The walking test was conducted on a treadmill inclined at 12% (speed of 1.8 m . s(-1)). The load was further increased every 3 min by the addition of a mass of one-twentieth of the body mass of the participant (plastic containers filled with water and added to a backpack carried by the participant). During the bicycle ergometry test, the workload was increased by 20 W every 2 min. All tests were performed until volitional exhaustion. During all tests, oxygen uptake, minute ventilation, tidal volume, respiratory frequency, heart rate, hydrogen ion concentration, base excess, and blood lactate concentration were analysed. The Pearson correlation coefficients between the weighted walking test and the commonly applied running and bicycle ergometry tests indicate a strong association with the new test in evaluating maximal oxygen uptake. The negligible differences in VO2max between the three tests for the male participants (running: 61.0 ml . kg(-1) . min(-1); walking: 60.4 ml . kg(-1) . min(-1); cycling: 60.2 ml . kg(-1) . min(-1)), and the fact that the females achieved better results on the walking test than the cycle ergometer test (running: 45.0 ml . kg(-1) . min(-1); walking: 42.6 ml . kg(-1) . min(-1); cycling: 40.1 ml . kg(-1) . min(-1)), confirm the suitability of the new method for evaluating aerobic power. The weighted walking test could be useful in the assessment of aerobic power in individuals for whom running is not advised or is difficult. In addition, the new test allows for determination of VO2max on small treadmills with a limited speed regulator, such as those found in specialist physiotherapy and fitness centres.

Acid-Base Equilibrium↗
PubMed1988

Social fate and long-term survival of patients with a recent myocardial infarction, after cardiac rehabilitation.

The aim of this study was to assess the social fate (work resumption) and long-term (four years) survival in 141 patients who completed a cardiac rehabilitation programme after a recent myocardial infarction. Out of the 100 patients who had been working up to recently before the myocardial infarction, 58 resumed their work. Of the predischarge evaluation (clinical data, resting radionuclide ventriculography, bicycle ergometry and 24-h ambulatory ECG monitoring) and bicycle ergometry after the rehabilitation, the only significant predictor of work resumption was a better exercise tolerance at discharge (P less than 0.02). Work was resumed by 68% of white-collar workers and by 52% of blue-collar workers. The four-year cardiac mortality in patients who completed the rehabilitation was 8.5% (N = 12). Four patients died during the first year. Clinical, ventriculographic and ergometric variables collected at hospital discharge, which were related to left ventricular dysfunction, were predictive of survival, while ventricular arrhythmias and markers of myocardial ischaemia were less predictive. The exercise testing performed after the rehabilitation programme was not useful for risk assessment. It is concluded that markers of left-ventricular dysfunction are predictive of a poor outcome; however, due to the low risk of patients who were referred to our rehabilitation unit and completed the rehabilitation programme, it seems reasonable for return to work to be based primarily on clinical information, exercise tolerance, and on psychological and social grounds. An additional extensive cardiological evaluation should be individually tailored for patients with specific symptoms.

Adult↗
PubMed1988

Four-year prognostic value of exercise-induced angina and painless ST segment depression early after myocardial infarction.

The aim of this study was to establish if angina pectoris and silent ST segment depression during pre-discharge exercise tests are predictive of 4 years survival after myocardial infarction. Accordingly, 377 consecutive hospital survivors of myocardial infarction underwent symptom-limited bicycle ergometry at hospital discharge. Sixty-eight patients had angina during exercise, 124 patients had silent ST segment depression and 184 had neither angina nor ST depression. The baseline demographic profile, exercise capacity during ergometry and radionuclide left ventricular ejection fraction were comparable in the three groups. The total mortality within 4 years in the three groups was 15%, 21% and 22%, and mortality due to reinfarction or sudden death was 10%, 17% and 14%. When patients on digitalis were excluded, the incidence of mortality due to reinfarction or sudden death in the group with painless ST segment depression was 11%. Coronary artery bypass grafting or percutaneous transluminal coronary angioplasty due to recurrent symptoms was performed in 41%, 20% and 18% respectively of the three groups. It is concluded that conditional upon modern treatment, including secondary prevention with beta-blockers and revascularization procedures in selected patients with symptoms refractory to medical therapy, exercise-induced angina and painless ST segment depression do not identify a group of patients at higher risk of sudden death or fatal reinfarction during the 4 years after myocardial infarction.

Angina Pectoris↗
PubMed1996

Determinants of exercise capacity in patients with coronary artery disease and mild to moderate systolic dysfunction. Role of heart rate and diastolic filling abnormalities.

BACKGROUND: To test the hypothesis that diastolic filling abnormalities are an important cause of exercise limitation in some patients with coronary artery disease we assessed the factors limiting exercise capacity in a group of patients with coronary artery disease in whom exercise limitation was greater than expected from the degree of resting left ventricular systolic dysfunction. METHODS AND RESULTS: We assessed the relationship between exercise capacity (maximal oxygen consumption) during erect cycle ergometry, heart rate, radionuclide indices of left ventricular systolic function (ejection fraction) and diastolic filling (peak filling rate, and time to peak filling) during semi-erect cycle ergometry in 20 patients (15 male, five female) who were aged 42-72 years (mean 61 years) and had angiographically proven coronary artery disease and evidence of reversible myocardial ischaemia on thallium scintigraphy. All patients exhibited marked exercise limitation (maximal oxygen consumption 8.7- 22.4 ml.min-1.kg-1--mean 15.9 ml.kg-1.min-1, which was 61.1 +/- 16% of age and gender predicted maximum) due to breathlessness or fatigue rather than angina, in spite of a mean ejection fraction for the group of 46.5% (range 30-67%). We also compared the diastolic filling characteristics of these patients during exercise with 10 healthy controls (age 38-66, mean 58 years; eight male, two female). Comparing diastolic filling characteristics, peak filling rate was higher and time to peak filling shorter both at rest and at peak exercise in controls than patients (peak filling rate 3.1 +/- 0.5 vs 2.2 +/- 0.9 EDV.s-1, P = 0.01 at rest and 8.3 +/- 0.8 vs 5.2 +/- 1.9 EDV.s-1, P < 0.0001 on exercise; time to peak filling 115.2 +/- 29.8 vs 228.9 +/- 71.7 ms, P < 0.0001 at rest and 52.8 +/- 16.2 vs 139.6 +/- 44.8 ms, P < 0.0001 on exercise respectively). On univariate analysis in the patients studied, maximal oxygen consumption was correlated with peak heart rate (r = 0.45 P = 0.04), peak exercise time to peak filling (r = -0.85 P < 0.0001), peak exercise peak filling time rate (r = 0.51 P = 0.019), and the relative increase in cardiac output i.e. cardiac output peak/cardiac output rest (r = 0.58, P = 0.008). There was no correlation between maximal oxygen consumption and resting indices of diastolic filling (peak filling rate and time to peak filling) or with resting or peak exercise ejection fraction. On multiple regression analysis, only peak exercise time to peak filling was significantly related to maximal oxygen consumption. CONCLUSION: We have observed a strong correlation between exercise capacity and indices of exercise left ventricular diastolic filling, and have confirmed previous studies showing a poor correlation with resting and exercise indices of systolic function and resting diastolic filling, in patients with coronary artery disease.

Adult↗
PubMed1990

Intra-arterial blood pressure monitoring in the evaluation of the hypertensive athlete.

To compare the blood pressure (BP) changes during a long-distance run with those during bicycle ergometry, nine normotensive and 18 hypertensive joggers were studied by means of ambulatory intra-arterial monitoring. In all subjects the ergometric test caused a progressive increase in systolic and little change in diastolic BP. Exertional BP levels were closely related to pre-exercise baseline values (P less than 0.001). A different BP pattern was observed during track running, as a sharp rise in systolic BP reaching maximum values 2-4 min after the start was recorded. Subsequently, systolic BP progressively declined throughout the run, only to increase again during the final sprint. Diastolic BP fell markedly at the onset of the run and then remained substantially stable throughout. A poor relationship was observed between the BP values at peak exercise and baseline levels (P less than 0.05) as the normotensives showed a significantly higher BP response than the hypertensives. On the contrary, during the ergometric test a parallel increase in BP was recorded in the normotensive and the hypertensive joggers. No correlation was found between the BP response to track running and to bicycle ergometry. These results indicate that the BP response to a standard stress test is not predictive of the BP changes determined by a long-distance run. The BP increase with strenuous effort seems to be reduced in hypertensive individuals, probably because of latent impairment of cardiac performance.

Adolescent↗