Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “BREATHING EXERCISES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 955 records · Page 53Linked to original sources
PubMed1988

Rate-responsive pacing as compared to fixed-rate VVI pacing in patients after ablation of the atrioventricular conduction system.

In 44 patients with supraventricular arrhythmias various pacemakers were studied after closed-chest ablation of the atrioventricular conduction system. There were 22 patients with a rate-programmable VVI pacemaker (Group I), 15 patients with an activity mode (ACTIVITRAX 8400) (Group II) and seven patients with a QT-mode pacemaker (QUINTECH 911) (Group III). To study both physical work capacity and heart-rate behaviour, exercise testing was performed using a treadmill. Sixteen patients in Group I (72.7%) complained of shortness of breath during exercise in comparison to four patients (26.7%) in Group II and three patients (42.9%) in Group III. Normal physical work capacity was observed in three of 22 patients (13.6%) in Group I and in all patients in Groups II and III. The heart rate both increased and decreased more rapidly at the onset and end of the stress test, respectively, in patients with activity-mode compared to patients with QT-mode pacing systems. These data show that, despite successful His-bundle ablation, both dyspnea and decreased work capacity are observed when VVI pacemakers are used. In contrast, the use of rate-responsive pacing systems leads to better cardiac performance.

Adult↗
PubMed1988

Exercise and the elderly.

Data from cross-sectional studies suggest that VO2max declines in adulthood at a rate of 0.40-0.45 ml.kg-1.min-1 per year in males and 0.30 ml.kg-1.min-1 per year in females. Longitudinal studies suggest that the loss is much greater for males, approximating 1.0 ml.kg-1.min-1 per year or more. The rate of loss may be greater in sedentary compared to active individuals. The decline in VO2max with age appears to be inevitable, and a major contributing factor may be the decline in maximal cardiac output. A reduced maximal heart rate is a consistent finding, and this may be due to decreased end-organ sensitivity to catecholamines. Maximal stroke volume may or may not decrease, and physical training status may be a determining factor. The most recent evidence suggests increased dependence upon the Frank-Starling mechanism, resulting in an increased stroke volume to offset the decline in maximal heart rate. Cardiac output is thought to be maintained in this manner. Use of this mechanism may depend upon the absence of underlying disease. Therefore, investigators who vigorously screen potential subjects for occult coronary disease may report findings different from those who do not. Maximal a-vO2 difference may or may not decline in the elderly. The research is divided, and there is support for both beliefs. Several factors typical of the elderly, including a decline in muscle mass, increased blood distribution to the skin during exercise, and a potentially lower capillary/fiber ratio, would contribute to a lower a-vO2 difference. On the other hand, in those subjects with reduced cardiac output, there may be greater dependence upon a-vO2 difference during maximal exercise. Pulmonary function does not appear to limit VO2max, although the elderly may be less efficient while breathing during exercise. However, the higher ventilation and higher ventilatory equivalent for oxygen observed during submaximal exercise could be due to higher relative stress in the elderly. Elderly males and females are capable of demonstrating a training effect in response to endurance training regardless of previous physical activity patterns and current training status. The degree of change with training, expressed in relative terms, appears to be comparable to that demonstrated by younger subjects. Physiological factors contributing to an increased VO2max as a result of training appear to be similar in elderly and younger subjects, with the possible exception of no change in maximal a-vO2 difference in the elderly. This point is somewhat controversial.(ABSTRACT TRUNCATED AT 400 WORDS)

Aging↗
PubMed2005

[Manual abdominal compression for the detection of expiratory flow limitation].

INTRODUCTION: Expiratory flow limitation (EFL) is a characteristic feature of chronic obstructive pulmonary disease (COPD) and leads to dynamic hyperinflation (DH) which is a major source of dyspnoea, particularly during exercise. STATE OF THE ART: A new technique for the detection of EFL, based on manual compression of the abdomen (MCA), was assessed both in normal subjects and patients with COPD. MCA was always associated with a moderate increase in pleural pressure and allowed the detection of EFL in a reproducible manner, in both the seated and supine postures. The technique was well tolerated. It was also a reliable method for the detection of EFL during exercise since EFL detection was effectively associated with the development of DH. Finally, MCA was also compared to NEP in patients with obstructive sleep apnoea syndrome (OSAS) and in these patients, MCA invariably increased expiratory flow whereas the NEP method produced flow limitation in some cases because of upper airway collapse. PERSPECTIVES: EFL detection with MCA may be clinically useful since EFL is a determinant of dyspnoea, affects ventilatory response to exercise as well as maximum exercise capacity. CONCLUSIONS: MCA is a reliable technique for the detection of EFL in different positions, during resting breathing or exercise, requiring neither special equipment nor patient cooperation.

Abdomen↗
PubMed2003

Feasibility of high-intensity, interval-based respiratory muscle training in COPD.

BACKGROUND: Specific respiratory muscle training can improve respiratory muscle function in patients with COPD, but the magnitude of improvement appears dependent on the magnitude of the training load. High training loads are difficult to achieve using conventional, constant loading techniques, but may be possible using interval-based training techniques. METHODS: To assess the feasibility of high-intensity respiratory muscle training, nine subjects with moderate-to-severe COPD (FEV(1) 34 +/- 12% predicted [mean +/- SD]) completed 8 weeks of interval-based respiratory muscle training combined with a general exercise program. This involved three 20-min sessions per week, each session comprising seven 2-min bouts of breathing against a constant inspiratory threshold load, each bout separated by 1 min of unloaded recovery. Inspiratory load was progressively incremented. Respiratory muscle strength (maximum inspiratory pressure generated against an occluded airway [PImax]) and endurance (maximum pressure generated against a progressively increasing inspiratory threshold load [Pthmax]) were measured before and immediately after the 8-week training period. RESULTS: By the third training session (week 1), subjects breathed against a threshold that required generation of pressures equivalent to 68 +/- 5% of the pretraining PImax. By week 8, this had increased to 95 +/- 12% of the pretraining PImax. On completion of training, PImax had increased by 32 +/- 27% (p < 0.05), Pthmax had increased by 56 +/- 33% (p < 0.05), and Pthmax/PImax had increased by 20 +/- 20% (p < 0.05). CONCLUSIONS: This study has demonstrated that high-intensity, interval-based respiratory muscle training is feasible in patients with moderate-to-severe COPD, resulting in significant improvements in respiratory muscle strength and endurance when performed three times a week for 8 weeks.

Aged↗
PubMed1982

Effect of the oronasal breathing route on sulfur dioxide-induced bronchoconstriction in exercising asthmatic subjects.

We undertook a study to determine how the oronasal breathing route affects the bronchoconstrictor response to sulfur dioxide (SO2) inhaled by asthmatic subjects during exercise. In 6 subjects, we compared the changes in specific airway resistance (SRaw) caused by breathing humidified air through a mouthpiece during 5 min of exercise on a bicycle ergometer (550 kpm/min) to the changes caused by breathing humidified air plus 0.5 ppm of SO2, (a) through a mouthpiece (oral breathing), (b) by facemask (oronasal breathing), and (c) by facemask with the mouth occluded (nasal breathing) during exercise. Breathing humidified air plus 0.5 ppm of SO2 through a mouthpiece or by facemask during exercise significantly increased SRaw in all 6 subjects, and breathing humidified air plus 0.5 PPM of SO2 by facemask with the mouth occluded significantly increased SRaw in 5 of 6 subjects. The increase in SRaw caused by breathing humidified air plus 0.5 PPM of SO2 through a mouthpiece was not significantly different from the increase caused by breathing SO2 by facemask (p greater than 0.05), but was significantly greater than the increase caused by breathing SO2 by facemask with the mouth occluded (p less than 0.05). These results indicate that although nasal breathing partially protected against SO2-induced bronchoconstriction in our subjects, both oral and oronasal breathing of low concentrations of SO2 during exercise can cause significant bronchoconstriction in people with asthma.

Adult↗
PubMed1993

Breathing pattern during and after maximal exercise testing in young untrained subjects and in obese patients.

More rapid and more shallow breathing (RSB) than usual, manifested by a lower tidal volume and greater breathing frequency at a given level of ventilation, may be caused by inspiratory muscle fatigue and pulmonary congestion. It has been observed during recovery in young trained adults after very high exercise levels and in middle-aged patients with cardiac disease, after their maximal work load. We studied the breathing pattern during and after exercise testing up to the maximal work capacity in a group of normal untrained, young people and in a group of young obese subjects. RSB was present in normal subjects after a work load which required a maximal O2 consumption near the theoretical value (93% in our cases) and was not present in obese patients probably because neither inspiratory muscle fatigue, nor pulmonary congestion occurs in these subjects. Maximal heart rate at peak of exercise was significantly higher in normal subjects and a direct correlation between delta Vt and maximal heart rate was found in all normal subjects. This is compatible with the hypothesis that RSB is mainly due to an initial interstitial pulmonary edema, as supposed by other authors.

Adult↗
PubMed1994

Diaphragm and lung afferents contribute to inspiratory load compensation in awake ponies.

We determined the effect of pulmonary vagal (hilar nerve) denervation (HND) and diaphragm deafferentation (DD) on inspiratory load compensation. We studied awake intact (I; n = 10), DD (n = 5), HND (n = 4), and DD+HND (n = 7) ponies at rest and during mild (1.8 mph, 5% grade) and moderate (1.8 mph, 15% grade) treadmill exercise before, during, and after resistance of the inspiratory circuit was increased from approximately 1.5 to approximately 20 cmH2O.l-1.s. During the first loaded breath in I ponies at rest, inspiratory time (TI) increased, expiratory time decreased, and inspiratory drive increased. There were minimal changes after the first breath, and inspiratory minute ventilation (VI) and arterial PCO2 did not change (P > 0.10) from control values. On the first loaded breath during exercise, TI increased but inspiratory drive either did not change or decreased from control values. TI and drive increased after the first breath, but the increases were insufficient to maintain VI and arterial PCO2 at control levels. First-breath load compensation remained after DD, HND, and DD+HND, but after DD+HND tidal volume and VI were compensated 5-10% less (P < 0.05) than in I ponies. In all groups inspiratory drive, tidal volume, and VI were markedly augmented on the first breath after loading was terminated with a gradual return toward control. We conclude that diaphragm and pulmonary afferents contribute to but are not essential for inspiratory load compensation in awake ponies.

Animals↗
PubMed1990

Effects of humid air breathing during arm or treadmill exercise on exercise-induced bronchoconstriction and refractoriness.

Although it has been reported that inhibitory prostaglandins may be a causal factor in exercise refractoriness, it is still unclear whether exercise-induced bronchoconstriction (EIB) and/or other specific "exercise factors" are necessary to trigger their release and render a subject refractory to subsequent exercise. The purpose of this study was to determine whether non-EIB-producing exercise with the legs or arms could produce refractoriness to a standard treadmill challenge. Eight asthmatic subjects with EIB completed three sessions consisting of two exercise challenges separated by a 30-min rest. In all sessions, the second challenge was done on a treadmill while breathing dry air. Conditions for Challenge 1 were the following: Session A = treadmill, dry air; Session B = treadmill, humid air; Session C = arm cranking, humid air. All three conditions produced a significant degree of refractoriness. There was a tendency for the percent protection index to be greater for Session A; however, no significant differences were found among the three sessions. Therefore, it can be concluded that although both exercise and bronchoconstriction may play a role in producing the refractory period, neither severe bronchoconstriction nor intense exercise with the same muscle groups are required to produce refractoriness.

Adult↗
PubMed2006

Breathing pattern and kinematics in normal subjects during speech, singing and loud whispering.

AIMS: We used for the first time a non-invasive optoelectronic plethysmography to assess breathing movements and to provide a quantitative description of chest wall kinematics during phonation. METHODS: Volumes of different chest wall compartments (abdomen and lung apposed to rib cage and abdomen) were assessed using optoelectronic plethysmography in 16 normal Italians (eight men) during reading, singing and high-effort whispering (HW). RESULTS: During phonation the breathing pattern was different from quiet breathing and exercise. (1) During phonation, tidal volume and expiratory time increased while inspiratory time decreased. The expiratory volume changes and flows during HW were considerably greater than during vocalization. During HW, the overall end-expiratory thoracic volume significantly decreased as a result of decreased volume of all compartments and essentially impinged on the maximal expiratory flow-volume curve. (2) While, as previously shown, during exercise the expired volume is due entirely to the abdomen, during phonation all three chest wall compartments contribute to it. Under all conditions studied breathing was, on average, more costal in females than in males but this was mainly related to different size rather than gender per se. CONCLUSIONS: Physical characteristics have a greater importance than gender in determining breathing pattern and chest wall kinematics during phonation. The activity of the control of expiration during phonation is more complex than during exercise.

Adult↗
PubMed1995

Contribution of the respiratory muscles to the lactic acidosis of heavy exercise in COPD.

Patients with COPD usually are limited in their exercise tolerance by a limited ventilatory capacity. Lactic acidosis induced by exercise increases the stress on the ventilatory system due to CO2 generated by bicarbonate buffering and hydrogen ion stimulation. Patients with COPD are often observed to increase blood lactate levels at low levels of exercise. We wished to determine whether patients with COPD who experience lactic acidosis do so because of respiratory muscle production of lactate. Eight patients with moderate to severe COPD (FEV1 = 43.5 +/- 11.6% predicted) and 5 healthy subjects performed 10 min of moderate constant work rate exercise either breathing spontaneously or volitionally increasing their ventilation for 5 min to approximate the peak minute ventilation seen during incremental exercise. During volitional increased ventilation, 3% CO2 was added to the inspirate to prevent alkalosis and hypocapnia. In neither the healthy subjects nor the COPD group was the end-exercise lactate level significantly higher during volitional ventilation increase than during spontaneous ventilation. Further, in the COPD patients, the blood lactate levels during volitional ventilation increase were much lower than during maximal exercise (averaging 2.4 vs 5.3 mmol/L) despite similar ventilation levels (averaging 50 and 53 L/min). We conclude that it is unlikely that the respiratory muscles have an important influence on the blood lactate level elevation seen during maximal exercise in COPD patients.

Acidosis, Lactic↗