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At least 595 records · Page 33Linked to original sources

PubMed2005

Exercise intolerance in patients with atrial fibrillation: clinical and echocardiographic determinants of exercise capacity.

Although exercise intolerance is a major symptom of patients with atrial fibrillation (AF), the factors limiting these patients' exercise capacity remains uncertain. This study evaluated the correlation of clinical and echocardiographic parameters with exercise capacity of patients with AF. In all, 73 patients (61 men and 12 women; mean age 61 years) with chronic AF were included in this study. Those patients with primary valvular diseases were excluded. Standard 2-dimensional and Doppler echocardiography was performed, and we averaged 10 consecutive measurements of each variable. Patients then underwent a symptom-limited treadmill exercise testing. We also measured patients' plasma levels of B-type natriuretic peptide before exercise testing. Of all clinical and echocardiographic parameters we assessed, age (r = -0.45, P = .006), ratio of early mitral inflow velocity to mitral annular velocity (r = -0.35, P = .032), and baseline heart rate were independent predictors of exercise capacity on multivariate regression analysis. In conclusion, patient's age, averaged ratio of early mitral inflow velocity to mitral annular velocity, and baseline heart rate provided useful information on exercise intolerance for patients with AF. Ratio of early mitral inflow velocity to mitral annular velocity, a noninvasive tool for estimating left ventricular filling pressure, may especially have important value for predicting functional capacity in this population as it has in individuals with in sinus rhythm.

Atrial Fibrillation↗

PubMed2026

The effect of combining visuo-vestibular exercises with manual therapy and exercise on sensorimotor function in chronic neck pain: A randomized controlled trial.

OBJECTIVE: To investigate whether adding visuo-vestibular exercises to standard manual therapy and exercise produces superior improvements in sensorimotor function, pain, balance, and functional disability in adults with chronic neck pain. METHODS: This prospective, randomized controlled trial enrolled 58 adults with chronic neck pain (≥3 months) allocated to a manual therapy and exercise group (MtE; n = 29) or MtE plus visuo-vestibular exercises (MtE-VVE; n = 29). Both groups completed 12 supervised sessions over six weeks with a daily home exercise programme. Outcomes were assessed at baseline, 6 weeks, and 12 weeks, and included pain intensity (Visual Analog Scale [VAS]), upper extremity reaction time, computerized posturography, the Neck Disability Index (NDI), and cervical muscle endurance. RESULTS: Fifty-four participants (27 per group) completed the study. Both groups improved significantly across all outcomes (p < 0.001). At 12-week follow-up, the MtE-VVE group demonstrated superior outcomes: activity-related pain was reduced by an additional 2.00 cm (95% CI: 0.75-3.25; p = 0.005), bilateral reaction time improved by 1.70 s (p = 0.001), eyes-open mediolateral sway decreased by 0.50 mm (p < 0.001), NDI score was 6.30 points lower (95% CI: 3.42-9.18; p < 0.001), and cervical flexion and extension endurance improved by 12.00 s and 27.70 s, respectively (p ≤ 0.020). CONCLUSION: Adding visuo-vestibular exercises to standard manual therapy and exercise produces clinically meaningful and sustained improvements in activity-related pain, sensorimotor function, postural control, and functional disability in adults with chronic neck pain, and may be recommended as an effective adjunctive intervention.

Humans↗

PubMed2005

Effects of calcium pyruvate supplementation during training on body composition, exercise capacity, and metabolic responses to exercise.

OBJECTIVE: We evaluated the effects of calcium pyruvate supplementation during training on body composition and metabolic responses to exercise. METHODS: Twenty-three untrained females were matched and assigned to ingest in a double blind and randomized manner either 5 g of calcium pyruvate (PYR) or a placebo (PL) twice daily for 30 d while participating in a supervised exercise program. Prior to and following supplementation, subjects had body composition determined via hydrodensiometry; performed a maximal cardiopulmonary exercise test; and performed a 45-min walk test at 70% of pre-training VO2 max in which fasting pre- and post exercise blood samples determined. RESULTS: No significant differences were observed between groups in energy intake or training volume. Univariate repeated measures ANOVA revealed that subjects in the PYR group gained less weight (PL 1.2 +/- 0.3, PYR 0.3 +/- 0.3 kg, P = 0.04), lost more fat (PL 1.1 +/- 0.5; PYR -0.4 +/- 0.5 kg, P = 0.03), and tended to lose a greater percentage of body fat (PL 1.0 +/- 0.7; PYR -0.65 +/- 0.6%, P = 0.07), with no differences observed in fat-free mass (PL 0.1 +/- 0.5; PYR 0.7 +/- 0.3 kg, P = 0.29). However, these changes were not significant when body composition data were analyzed by MANOVA (P = 0.16). There was some evidence that PYR may negate some of the beneficial effects of exercise on HDL values. No significant differences were observed between groups in maximal exercise responses or metabolic responses to submaximal walking. CONCLUSIONS: Results indicate that PYR supplementation during training does not significantly affect body composition or exercise performance and may negatively affect some blood lipid levels.

Adult↗

PubMed2003

Effects of oral magnesium therapy on exercise tolerance, exercise-induced chest pain, and quality of life in patients with coronary artery disease.

Previous studies have demonstrated that magnesium supplementation improves endothelial function in patients with coronary artery disease (CAD). However, the impact on clinical outcomes, such as exercise-induced chest pain, exercise tolerance, and quality of life, has not been established. In a multicenter, multinational, prospective, randomized, double-blind and placebo-controlled trial, 187 patients with CAD (151 men, 36 women; mean +/- SD age 63 +/- 10 years, range 42 to 83) were randomized to receive either oral magnesium 15 mmol twice daily (Magnosolv-Granulat, total magnesium 365 mg provided as magnesium citrate) (n = 94) or placebo (n = 93) for 6 months. Symptom-limited exercise testing (Bruce protocol) and responses given on quality-of-life questionnaires were the outcomes measured. Magnesium therapy significantly increased intracellular magnesium levels ([Mg]i) in a substudy of 106 patients at 6 months compared with placebo (35.5 +/- 3.7 vs 32.6 +/- 2.9 mEq/L, p = 0.0151). Magnesium treatment significantly increased exercise duration time compared with placebo (8.7 +/- 2.1 vs 7.8 +/- 2.9 minutes, p = 0.0075), and lessened exercise-induced chest pain (8% vs 21%, p = 0.0237). Quality-of-life parameters significantly improved in the magnesium group. These findings suggest that oral magnesium supplementation in patients with CAD for 6 months results in a significant improvement in exercise tolerance, exercise-induced chest pain, and quality of life, suggesting a potential mechanism whereby magnesium could beneficially alter outcomes in patients with CAD.

Administration, Oral↗

PubMed2002

The effects of exercise intensity on thermoregulatory responses to exercise in women.

We investigated the influence of altering exercise intensity (150, 300, and 450 kpm/min) on the resetting of the core temperature threshold for the onset of the sweating rate (M(sw)) and the alteration of sweating sensitivity during the menstrual cycle in women. Five women underwent cycling exercise for 30 min in both the luteal and follicular phases under controlled neutral environmental conditions (T: 25 degrees C, RH: 55%). A significantly higher rectal temperature (T(re)) was seen in the luteal phase at all exercise intensities, and the same time course of the T(re) response with a constant difference of approximately 0.2 degrees C was shown between the follicular phase and the luteal phase. The T(re) threshold for M(sw) was also apparently shifted rightward a constant value of 0.2 degrees C from the follicular phase to the luteal phase, independent of the alteration of exercise intensity. The slope of the M(sw)-T(re) relationship in the follicular phase did not differ from that in the luteal phase. These results indicate that (1) a rightward shift in the T(re) threshold from the follicular phase to the luteal phase can be observed independent of any alteration of the exercise intensity; and (2) the sensitivity of M(sw) is also not physiologically influenced by exercise intensity. Thus, alterative thermoregulation during the menstrual cycle was fundamentally unaffected by the change of exercise intensity.

Adult↗

PubMed1990

Skeletal muscle limits the exercise tolerance of renal transplant recipients: effects of a graded exercise training program.

Sixteen renal transplant recipients were studied before and after they had participated in a 24-week exercise training program to determine (1) the nature of the factors explaining their impaired exercise tolerance, and (2) their adaptative responses to exercise training. During progressive treadmill exercise to exhaustion prior to training, renal transplant recipients stopped exercising at lower peak rates of oxygen consumption (VO2max) (29.0 +/- 7.8 47.9 +/- 9.1 mL O2.kg-1.min-1; P less than 0.001) and ventilation (55.9 +/- 13.2 v 124.0 +/- 22.2 L.min-1; P less than 0.0001), and at lower peak heart rates (169 +/- 22 v 196 +/- 9 beats.min-1; P less than 0.05) and peak blood lactate concentrations (5.0 +/- 2.1 v 11.5 +/- 4.0 mmol.L-1; P less than 0.001) than did controls. None showed a plateau in oxygen consumption with increasing workload. Exercise time to exhaustion was also significantly shorter in renal transplant recipients (9.5 +/- 1.8 v 16.0 +/- 1.3 min; P less than 0.0001). After training, exercise time to exhaustion (12.0 +/- 2.0 min; P less than 0.001), VO2max (37.5 +/- 4.8 mL O2.kg-1.min-1; P less than 0.05), maximum ventilation rate (68.5 +/- 14.0 L.min-1; P less than 0.05), peak blood lactate concentrations (7.8 +/- 1.8 mmol-L-1; P less than 0.001), and the rate of oxygen consumption at a blood lactate concentration of 2.0 mmol.L-1 (22.5 +/- 2.5 v 16.5 +/- 2.2 mL O2.kg-1.min-1; P less than 0.001) had all increased significantly.(ABSTRACT TRUNCATED AT 250 WORDS)

Adaptation, Physiological↗

PubMed1998

Exercise training in heart failure improves quality of life and exercise capacity.

AIMS: Benefit from exercise training in heart failure has mainly been shown in men with ischaemic disease. We aimed to examine the effects of exercise training in heart failure patients < or = 75 years old of both sexes and with various aetiology. METHODS AND RESULTS: Fifty-four patients with stable mild-to-moderate heart failure were randomized to exercise or control, and 49 completed the study (49% > or = 65 years; 29% women; 24% non-ischaemic aetiology; training, n = 22; controls, n = 27). The exercise programme consisted of bicycle training at 80% of maximal intensity over a period of 4 months. Improvements vs controls were found regarding maximal exercise capacity (6 +/- 12 vs -4 +/- 12% [mean +/- SD], P < 0.01) and global quality-of-life (2 [1] vs 0 [1] units [median ¿inter-quartile range¿], P < 0.01), but not regarding maximal oxygen consumption or the dyspnoea-fatigue index. All of these four variables significantly improved in men with ischaemic aetiology compared with controls (n = 11). However, none of these variables improved in women with ischaemic aetiology (n = 5), or in patients with non-ischaemic aetiology (n = 6). The training response was independent of age, left ventricular systolic function, and maximal oxygen consumption. No training-related adverse effects were reported. CONCLUSION: Supervised exercise training was safe and beneficial in heart failure patients < or = 75 years, especially in men with ischaemic aetiology. The effects of exercise training in women and patients with non-ischaemic aetiology should be further examined.

Activities of Daily Living↗

PubMed1998

Visual and brainstem auditory evoked potentials and maximal aerobic exercise: does the influence of exercise persist after body temperature recovery?

Transversal studies have shown a strong correlation between specific evoked potential (EP) values and specific physical activities, as well as between EP values and the amount of training. Prior to longitudinal studies investigating the effect of training in EPs, it is mandatory to determine whether a recent training session could interfere with regular EP recording. Exercise-induced hyperthermia is known to modify EP values. The purpose of the study was to determine whether an acute exercise can induce EP modification persisting after body temperature recovery. We measured two sets of visual evoked potentials (VEPs) and brainstem auditory evoked potentials (BAEPs) in 16 males (8 cyclists and 8 sedentary peers), one before and the other after a maximal cycloergometric graded exercise test. The second test was performed immediately after body temperature recovery. We chose to test cyclists, as their specific training corresponded to the exercise test we performed on a cycloergometer. The repeated measures before and after the exercise test showed no significant differences, neither in VEPs nor in BAEPs, for any subject of the study. Recording VEPs and BAEPs in cyclists, we observed no difference related to this particular sport training. This study showed that VEP and BAEP values were similar to those measured before a maximal exercise when body temperature returned to pre-exercise value. This original work demonstrated that VEP and BAEP recordings can be reliably performed after a recent training session, provided body temperature has returned to basal level.

Adolescent↗

PubMed2004

Adherence to exercise in later life: how can exercise on prescription programmes be made more effective?

A broad consensus has emerged in relation to the desirability of promoting exercise among a variety of 'at risk' groups via 'exercise on prescription' (EoP) schemes, as an alternative to orthodox, biomedical approaches to the management of health problems. Underpinning the rationale for such schemes is the notion that they can act as vehicles for encouraging long-term adherence to exercise. Whilst there is a common sense appeal to using EoP schemes to promote exercise, research to date suggests that evidence of their impact is limited. This paper attempts to make sense of these findings in the light of recent debates about adult lifestyles and exercise. More specifically, it brings work in the sociology of leisure to bear on the topic, on the premise that any study of adults' propensity towards sustainable physical activity needs to be viewed as an aspect of their lives 'in the round'. Such an analysis points up the value of synthesizing perspectives from across the disciplinary divide in order to shed light on particular 'problems', which obviate the necessity for further empirical work. The paper concludes by identifying a number of implications for public health policy and practice with respect to the matter of encouraging lifelong participation in sport and exercise in general, and via EoP schemes in particular. One such implication is the development of a model for understanding participation that shifts the emphasis away from a focus on motivation and behaviour change per se towards satisfaction and enjoyment through the development of skills and relationships. Reconceptualizing the matter of participation in this way is likely to lead not only to a more realistic appreciation of what can be expected from EoP schemes, but also a more adequate understanding of adherence to exercise in later life.

Adult↗

PubMed1998

Delayed VO2 kinetics during ramp exercise: a criterion for cardiopulmonary exercise capacity in chronic heart failure.

PURPOSE: Kinetics of VO2 at onset of constant work rate exercise was previously shown to be slowed in patients with chronic heart failure (CHF) compared with that in healthy normals. Because bicycle ergometry with ramp protocol is usually used for exercise testing with CHF patients, it would be of practical importance if it can be shown that a delay in the time interval of linear increase of VO2 (TILIV) to work rate occurs after beginning ramp exercise. Data of central hemodynamics (CHF) and noninvasive cardiopulmonary parameters (CHF, normals) should also correlate with VO2 delay time if this parameter is related to cardiopulmonary exercise capacity. METHODS: Fifteen males with CHF (mean +/- SEM: age 52 +/- 2 yr; ejection fraction 32 +/- 4%; peak cardiac index 3.9 +/- 0.3 L x m(-2) x min(-1)) and 28 healthy males (50 +/- 1 yr) were assessed. During ramp bicycle ergometry (3 min unloaded, work rate increments of 12.5 W x min(-1)), VO2 was measured breath by breath. RESULTS: After the onset of ramp exercise, there was a difference in the TILIV between patients and normals (83.7 +/- 3.6 vs 66.8 +/- 2.9 s; P < 0.001). Significant differences between both groups were also found for VO2 at ventilatory threshold (VT) (10.1 +/- 0.1 vs 15.2 +/- 0.7 mL x kg(-1) x min(-1); P < 0.0001), VO2 at VT relative to predicted VT (58 +/- 4 vs 97 +/- 4%; P < 0.0001), peak VO2 (13.2 +/- 1.0 vs 34 +/- 1.4 mL x kg(-1) x min(-1), P < 0.001), and increase of systolic blood pressure (36 +/- 7 vs 71 +/- 5 mm Hg; P < 0.0001). In CHF, the TILIV correlated significantly with peak cardiac index and VO2 at VT (r = -0.71; P < 0.005 each), relative value of VO2/kg at VT (r = -0.61; P < 0.03), peak VO2/kg (r = -0.63; P < 0.01), and increase of systolic blood pressure (r = -0.52; P < 0.02). In the normals only VO2/kg at VT correlated significantly with TILIV (r = -0.41; P < 0.03). In patients, stepwise regression analysis identified three predictors which could explain 79% of the variance of TILIV: VO2/kg at VT (r2 = 0.51), peak cardiac index (r2 = 0.20), and peak VO2/kg (r2 = 0.08). CONCLUSION: TILIV, determined at the onset of ramp exercise, is prolonged in CHF patients compared with that in normals and reflects severity of functional impairment because of reduced cardiac index and aerobic capacity. TILIV can provide information about changes in cardiopulmonary exercise capacity and thus can be used for follow-up and treatment studies in CHF.

Cardiac Output, Low↗

PubMed1998

Effects of prior exercise on exercise-induced arterial hypoxemia in young women.

Twenty-eight healthy women (ages 27.2 +/- 6.4 yr) with widely varying fitness levels [maximal O2 consumption (VO2 max), 31-70 ml . kg-1 . min-1] first completed a progressive incremental treadmill test to VO2 max (total duration, 13.3 +/- 1.4 min; 97 +/- 37 s at maximal workload), rested for 20 min, and then completed a constant-load treadmill test at maximal workload (total duration, 143 +/- 31 s). At the termination of the progressive test, 6 subjects had maintained arterial PO2 (PaO2) near resting levels, whereas 22 subjects showed a >10 Torr decrease in PaO2 [78.0 +/- 7.2 Torr, arterial O2 saturation (SaO2), 91.6 +/- 2.4%], and alveolar-arterial O2 difference (A-aDO2, 39.2 +/- 7.4 Torr). During the subsequent constant-load test, all subjects, regardless of their degree of exercise-induced arterial hypoxemia (EIAH) during the progressive test, showed a nearly identical effect of a narrowed A-aDO2 (-4.8 +/- 3.8 Torr) and an increase in PaO2 (+5.9 +/- 4.3 Torr) and SaO2 (+1.6 +/- 1.7%) compared with at the end point of the progressive test. Therefore, EIAH during maximal exercise was lessened, not enhanced, by prior exercise, consistent with the hypothesis that EIAH is not caused by a mechanism which persists after the initial exercise period and is aggravated by subsequent exercise, as might be expected of exercise-induced structural alterations at the alveolar-capillary interface. Rather, these findings in habitually active young women point to a functionally based mechanism for EIAH that is present only during the exercise period.

Adolescent↗

PubMed2002

Antihypertensive effects of aerobic exercise in middle-aged normotensive men with exaggerated blood pressure response to exercise.

An exaggerated blood pressure (BP) response to physical exertion among normotensive subjects is considered a significant risk factor for future hypertension. The purpose of this study was to examine whether regular aerobic exercise can lead to a reduction in hypertensive risks in patients with such a high-risk profile. Thirty-five sedentary men (46 +/- 2 years old) with normal BP at rest but an exaggerated BP response during exercise were randomly assigned to an exercise or control group for 12 weeks followed by an 8-week washout period. The subjects were then crossed over to the alternate group for an additional 12-week period. The exercise training consisted of 3 days per week of stationary bicycling for 45 min at 50-60% of the heart rate reserve. The treatment effects were evaluated using the method of Hills and Armitage. The training-induced reduction in resting BP was not statistically significant. In ambulatory BP monitoring, the averages of 24-h and daytime systolic and diastolic BP were significantly lower, but nighttime BP remained unchanged after training. During ergometric exercise, significant decreases were observed in systolic and diastolic BP and plasma norepinephrine concentration measured at the submaximal workloads. M-mode echocardiographic and Doppler-derived left ventricular variables were not significantly affected by training. These findings suggest that regular aerobic exercise attenuates BP elevations during physical exertion and daytime activities mainly as a result of the reduction in enhanced sympathetic nervous tonus, which may in turn play a role in lowering the risk for hypertension in normotensive subjects with an exaggerated BP response to exercise.

Blood Pressure↗

PubMed1992

[Comparison of exercise capacity evaluated by cardiopulmonary exercise test and hemodynamic parameters in patients with atrial septal defect].

We evaluated the maximal exercise tolerance using cardiopulmonary exercise testing, and investigated the relation of the hemodynamic parameters such as mean pulmonary artery pressure (PAm) and pulmonic-to-systemic flow ratio (Qp/Qs) to exercise tolerance in 18 adult patients consecutively. All the patients had atrial septal defect (ASD). Maximal oxygen uptake (VO2 max) averaged only 21.6 +/- 5.6 ml/min/kg and 63.5 +/- 16.2% of the predicted values (VO2max). And anaerobic threshold averaged 12.5 +/- 2.3 ml/min/kg and 56.7 +/- 12.4% of the predicted values. There were 2 patients who had marked pulmonary hypertension (PH, PAm more than 44 mmHg). Maximal exercise tolerance of these patients was severely impaired, and %VO2max was only 45.9% and 46.2% respectively. In patients without PH (PAm less than 20 mmHg), however %VO2 max ranged widely from 100.3 to 44.7% and PAm correlated with %VO2max weakly (r = -0.53, p less than 0.05). But there was a significant inverse relationship between Qp/Qs and %VO2max(r = -0.85, p less than 0.01). In 16 patients without PH, maximal O2-pulse during exercise was also inversely correlated with Qp/Qs (r = -0.76, p less than 0.01). The relation between PAm and %VO2max suggests that afterload on the right ventricle may be an important determinant of exercise capacity in patients with PH. And the relation between Qp/Qs and %VO2max or Qp/Qs and % maximal O2-pulse suggests that Qp/Qs may also be a very important determinant factor of exercise capacity in patients without PH.

Adult↗

PubMed1994

Differences in u-PA and t-PA increase during acute exercise: relation with exercise parameters.

Plasma levels of urokinase-type (u-PA Ag) and tissue-type (t-PA Ag) plasminogen activator are both enhanced during physical exercise. Whether, the extent of the increase and the post-exercise clearance rate of the two activators are comparable is not known. We studied the changes in u-PA Ag, t-PA Ag and t-PA activity during a standardized exercise test comprising submaximal and maximal exercise intensity. During submaximal (recreational) exercise, increases in u-PA are mainly due to changes in plasma volume, submaximal exercise demonstrates a continuous rise in level of t-PA Ag. During maximal performance peak levels of u-PA and t-PA Ag do not coincide in time and magnitude, moreover, u-PA Ag rather than t-PA Ag is related to t-PA Act. From these results we conclude that independent mechanisms regulate the exercise-induced plasma levels of u-PA and t-PA.

Adult↗

PubMed1993

The benefits and risks of exercise training: the exercise prescription.

The physiologic responses to exercise are mediated by a complex interaction of central, peripheral, and neurohumoral stimuli designed to increase cardiopulmonary function. With repetitive exercise, significant cardiovascular and muscular adaptations occur that facilitate and enhance the response to exercise. Exercise is beneficial not only to younger healthy individuals, but to patients with many chronic medical conditions and to elderly individuals as well. Physical activity has a role in the reduction of major cardiac risk factors and in both the primary and secondary prevention of cardiac events. With proper evaluation and counseling, exercise can be performed safely, even among patients with cardiovascular and other chronic diseases. Given the high percentage of the U.S. population whose sedentary lifestyle predisposes them to the development of cardiovascular disease and the numerous beneficial effects of exercise, it is prudent to prescribe exercise as a means of improving individual and general public health.

Exercise↗

PubMed1993

Exercise testing in cardiac rehabilitation. Role in prescribing exercise.

Graded exercise tests provide useful information for the prescription of exercise for cardiac patients. The responses to graded exercise depend on the mode of testing. The observed heart rate and electrocardiographic responses during graded exercise are used to establish an appropriate level or intensity of exercise at which the patient may participate safely. This article specifically addresses the role of exercise testing for the prescription of exercise in cardiac rehabilitation.

Adult↗

PubMed1989

Effect of exercise duration on lactate kinetics after short muscular exercise.

Arterial blood lactate concentrations were measured in six normal males before, during and after 3- and 6-min bicycle exercises performed at three different work rates. The lactate recovery curves were fitted to a bi-exponential time function consisting of a rapidly increasing and a slowly decreasing component, which supplied an accurate representation of the changes in lactate concentration. Variations in the parameters of this mathematical model have been studied as a function of the duration of exercise and of the work rate, showing a clear dependence on exercise duration such that increasing exercise length decreases the velocity constants of the fitted curves. In terms of the functional meaning which can be given to these constants, this result indicates that extending exercise duration from 3 to 6 min reduces the ability of the whole body to exchange and remove lactate. This effect did not qualitatively modify the one already described, which is due to increased work rates, but it shifted the ability to exchange and remove lactate towards lower values. The main conclusion of the study is that lactate kinetic data vary as a function of time during exercise. This inference must be accounted for in the interpretation of lactate data obtained during muscular exercise.

Adult↗

PubMed1996

Does the amount of exercising muscle alter the aerobic demand of dynamic exercise?

The primary purpose of this study was to determine if the aerobic demand for production of specified power outputs is altered by distribution of work between the arms and legs compared with when all the work is performed by the legs. Because of the important exercise training implications, a secondary purpose of this study was to determine if the exercising muscle mass affects the cardiorespiratory demands at specified rating of perceived exertion (RPE) levels and blood lactate concentrations. Nine healthy adults completed leg cycling and combined arm and leg exercise on an Airdyne using a discontinuous protocol. Repeated measures ANOVA revealed that oxygen uptake for the combined arm and leg exercise averaged 0.04 1.min-1 greater (p < 0.05) than for leg cycling at the same external power outputs. However, RPE levels at specified power outputs were lower (p < 0.05) with combined arm and leg exercise than leg cycling. At specified RPE levels and blood lactate concentrations, oxygen uptake and heart rate values were higher (p < 0.05) for combined arm and leg exercise than leg cycling. From these findings we conclude that: (1) the addition of arm exercise to leg cycling results in a reduction in RPE, but a minimal increase in oxygen consumption to perform a given power output, and (2) if training intensity is established by RPE or blood lactate concentration, use of muscle mass larger than that used in leg cycling should allow a greater cardiorespiratory training effect.

Adult↗